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eBay listings that quote us incorrectly or without credit may be
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Tuners are listed alphabetically by manufacturer and in alphabetical and numerical sequence by model number. In parentheses after the model number are the year of introduction and most recent list price, and/or the original list price if indicated by "orig" (special thanks to David Rich of The Audio Critic for copies of historical material from his reference library). Please
see the On-Deck Circle for tuners that we know very little about or that we're not sure merit a writeup.
Hafler DH-330 (1982, $425)
Hafler DH-330K (kit - 1984, $400) owner's manual, front end schematic, review)
The only Hafler tuner that is reputed to be halfway decent is the very common, ugly-looking FM-only DH-330. Our contributor Ed (VE) says, "The Hafler tuner is a computer-controlled unit with varactor tuning, 3 in the RF and 2 for a buffered local oscillator. The DH-330's selectivity can be improved with the addition of a ceramic filter IF amp at the mixer output. This mod is not extensive but does require parts selection. The transistor amp is easy enough but the ceramic filter is another story, as filters can vary significantly in characteristics and must be selected. The selection process requires a good scope, an FM signal generator for the sweep signal and another FM tuner to provide a source for the 10.7 MHz signal required to pick out a good one. I did not look at the audio but one can, from experience, assume that an increase in size and type of capacitors in the audio path reduce bass distortion due to phase delay."
Our contributor Joe says, "In comparing the Hafler DH-330 against my other tuners/receivers I find it just a little bit lacking on front end selectivity. It does a pretty credible job in most situations except for a strong station next to a weak one." Thanks to Joe for creating the front end schematic linked above. And Ed adds, "A word of caution on the DH-330. Yes, it does have a headphone jack; however, it is intended for use with high-impedance headphones, not for use with 32-ohm or lower phones. The headphone jack connects directly to a dual 10K volume control, and then back to an op-amp." The DH-330 can sell for almost any price on eBay, from under $50 to over $150, and the record low and high are $25 in 10/07 and $175 in 1/08. Be careful and know what you're buying, because the DH-330 was available both factory-built and in kit form as model no. DH-330K, as indicated above. The superb owner's manual contains the instructions for kit assembly as well as operation.
Harman/Kardon: There are several Harman/Kardon tuners in our On-Deck Circle and on the Tube Tuners page for which we'd like to get some basic information. If you've used any of them, please post the details in our FMtuners
Harman/Kardon Citation 14 (1973, $525, with cabinet, without cabinet, back 1, back 2, inside 1, inside 2, ad, schematic, service manual, user manual)
Harman/Kardon Citation 15 (1973, $395, with cabinet, without cabinet, back, inside, schematic, service manual, user manual)
Below, our contributor Eli outlines the features and specs of the Citation 14, Citation 15 and Citation 18 (which also has its own separate entry below). All of them are FM-only tuners. Our contributor Esmond adds, "The 14 has three circuit boards on the chassis top and another three on the underside. I imagine the 15 does too, as three PCBs just isn't enough. The RF board with all those LC filters is completely sealed inside an enclosure that can't be removed without removing another PCB or two first, and HK doesn't even list the transistor types. You were expected to buy the whole 'FM front end' assembly for servicing purposes. The audio sections of the 14 use a large number of 2N3417 transistors; these days I guess you would use BC639. The PSU uses a multi-section electro which could be hard to source these days. *Very* nice design and build quality." Nice Citation 14s usually sell for $140-260 on eBay, but $75-100 is more likely for cosmetically challenged ones. The Citation 15 can sell for almost anywhere from $50-200 on eBay, depending on condition; to illustrate, a decent one with a wood cabinet went for $64 in 3/09, but another fetched $240 in 5/09 (go figure). Here's Eli: "An eBay listing said that the 14/15 had the first PLL MPX in a production tuner, but I don't know whether this is true. Common to all three:
* Patented "Quieting Meter" that measures the signal-to-noise ratio of the received
Citation Fourteen (1973-77):
* All-metal buttons and switches
* Single IF bandwidth
* Rear-panel Muting threshold control
* Rear-panel Stereo threshold control
* Large, heavy metal tuning flywheel
* Thick, heavy aluminum faceplate and overall very substantial construction on essentially the same chassis for all three models
* Fourteens and Fifteens were all finished in silver brushed aluminum, as far as I can tell. Eighteens were nearly all black-faced, but there are some silver-faced Eighteens out there.
* Unusual rounded-corner walnut cabinets were available, along with rack-mount kits and even a screened metal rack designed to hold one of these tuners along with a matching 16 power amp and an 11, 17 or 17-S preamp (the 17-S matches the 18 styling and is simpler than the 11 and 17)
* On-board Dolby B noise reduction.
* Five-gang tuning capacitor
* Ratio detector
* Large black sealed "Nine-Pole LC Toroidal Linear Phase IF Filter" made by Filtech
* Front panel features:
Switch for internal Dolby NR adapter
400 Hz reference tone at level equivalent to 50% modulation
1/4" stereo phone plug receptacle for tape out
L and R gain control sliders
3-position Mono/Auto/Stereo Only switch
Switch for two levels of stereo noise filtering
Large center tune and quieting meters
Horizontal drum tuning dial scale with very large numbers
Unusual green-colored backlit displays for meters and dial scale
* Rear panel features:
Fixed and Variable audio outputs
X and Y oscilloscope outputs
Composite signal output for external 4-channel adapter
75- and 300-ohm screw antenna terminals
75-ohm antenna coax F-connector
Switched AC convenience outlet
IHF Usable Sensitivity: 2.0 µV
Selectivity: 60 dB
Limiter Saturation: > 2.0 µV @ +/- 75 kHz (-1 dB)
THD @ 1 kHz: mono: 0.25%, stereo: 0.35%
Signal to Noise ratio: -70 dB minimum
Image rejection: < -100 dB
Fundamental Plus 1/2 IF: > -100 dB
IF Rejection: < -100 dB
AM Rejection: 60 dB minimum
Capture Ratio: > 2.0 dB
SCA Rejection: Inaudible
Pilot Signal Rejection: < 50 dB
Subcarrier Suppression: < 400 Hz, -13.7 dB @ 10 kHz, Maximum error: +/- 0.5 dB
Citation Fifteen (1973-77):
* Four-gang tuning capacitor
* Ratio detector
* Large black sealed "Nine-Pole LC Toroidal Linear Phase IF Filter" made by Filtech
* Front panel features:
Switch for external Dolby NR adapter
400 Hz reference tone at level equivalent to 50% modulation
1/4" stereo phone plug receptacle for tape out
L and R gain control sliders
Stereo noise filter switch
Large center-tune and quieting meters
Horizontal drum tuning dial scale with very large numbers
Unusual green-colored backlit displays for meters and dial scale
* Rear panel features:
Fixed and Variable audio outputs
Inputs and outputs for external adaptor (these may be used for any other type of adapter you choose, or used for a tape recorder loop or input for another source component to your system)
Composite signal output for external 4-channel adapter
75- and 300-ohm screw antenna terminal
Switched AC convenience outlet
IHF Usable Sensitivity: 2.0 µV
Selectivity: 60 dB
Limiter Saturation: < 2.0 µV @ +/- 75 kHz (-1 dB)
THD @ 1 kHz: mono: 0.25%, stereo: 0.35%
S/N Ratio: -70 dB minimum
Image Rejection: > -90 dB
Fundamental Plus 1/2 IF: > -90 dB
IF Rejection: > -90 dB
AM Rejection: 60 dB minimum
Capture Ratio: < 2.0 dB
SCA Rejection: Inaudible
Pilot Signal Rejection: > 50 dB
Subcarrier Suppression: > 50 dB
Multiplex Separation @ 1 kHz: 45 dB
Citation Eighteen (1978-79):
* Five-gang tuning capacitor
* Ratio detector
* One 3-pin and one 4-pin ceramic IF filter (equivalent to 3 filters, total)
* Two wideband 2-watt stereo amplifiers for headphones (but will also drive efficient speakers)
* Plug-in circuit boards for easy repair or modification
* Very large potted power supply transformer
* Very nicely painted black chassis with very informative white labels silk-screened on
* Front panel features:
Switch for external processor loop
Switch for 25 µS de-emphasis (intended for Dolby FM)
Switch for stereo noise filter
Two(!) 1/4" stereo headphone jacks
Monitor level knob to control headphone output
Art Deco-style quieting meter (no center tune meter)
"IN TUNE" beacon to tell you when you're right on channel
Slide rule tuning dial with illuminated pointer, attractive backlit green numbers and a mirrored center section for accurate tuning
without parallax error
3-position Auto/Stereo Only/Mono switch
Unique 3-position Muting switch: when set to Wide, some interstation noise may be heard when tuned to the immediate left or right of a
strong signal. When set to Narrow, the tuner: "will mute whenever the IN TUNE beacon is not illuminated, denoting that the tuner is
off the center of a broadcast channel..."
* Rear panel features:
L+R audio outputs with ganged level control
Inputs and outputs for external processor (these may be used for a tape recorder loop or input for another source component to your system)
75-and 300-ohm spring-loaded antenna terminals
75-ohm antenna coax F-connector
* Specifications (Amplifier):
2 watts per channel @ 8 ohms with 0.1% THD, 20 Hz - 20 kHz
Rise time: 5 µS
* Specifications (Tuner):
30 dB Quieting Sensitivity mono: better than 11.2 dBf (2.0 µV)
50 dB Quieting Sensitivity mono: better than 15.1 dBf (3.2 µV)
50 dB Quieting Sensitivity Stereo: better than 37.3 dBf (40 µV)
THD @ 1 kHz: better than 0.15% mono (0.09% typical), better than 0.3% stereo (0.25% typical)
S/N ratio: -74 dB mono, -64 dB stereo
Capture ratio: 1.5 dB
Selectivity: 70 dB
IF Rejection: FM 100 dB
Image Rejection: FM 100 dB
Fundamental Plus 1/2 IF Rejection: 100 dB
SCA Rejection: 63 dB
19 kHz and 38 kHz Rejection: 60 dB
AM Rejection: 55 dB
Mute Suppression: 70 dB
Multiplex separation @ 1 kHz: better than 50 dB
Audio Frequency response (before de-emphasis): 10 Hz-50 kHz +/- 0.5 dB"
Harman/Kardon Citation 18 (1977, $595, front1,
front2, front3, back 1, back 2, technical manual, schematics and alignment guide)
The Citation 18, a solidly built 5-gang analog tuner with good sensitivity and decent sound, was available in black or (rare) silver. It has only two filters, but one is the old 4-pin type that is equivalent to two modern 3-pin filters. We thought the Citation 18 had wide and narrow IF bandwidth settings, but our contributor Eli corrected us: "The Citation 18 doesn't actually have wide and narrow IF bandwidths. The wide and narrow switch affects only the bandwidth of the muting. It's quite a strange and useless (to me) feature. I wonder if the designer intended to have two tuning bandwidths, but the accountants ($) or the marketers (deadline) got to it and they used the already-added switch to perform this useless function." It does have adjustable muting and stereo-mono thresholds, and TWO front-panel headphone jacks with an adjustable volume control. Inside, the Citation 18's plug-in circuit boards should make it easy to work on if one can read the schematics. Bill Ammons aligned and tweaked a Citation 18 and says, "For a tuner with only 3 ceramic filters it has very good 400 kHz selectivity and about 6 to 10 dB of 200 kHz selectivity." A contributor to our FMtuners group posted a nice writeup on the Citation 18.
Our contributor doug s. says that compared to his refurbished Tandberg 3001A, his upgraded Citation 18 has "better soundstaging and warmth, with equal detail," and it is also much more sensitive than his other tuners. doug said, "The Citation 18 has the best blend circuit of any tuna I have tried. It preserves the high-frequency ambiance and details, while only slightly narrowing the soundstaging." He added, "I currently have three Citation 18s: my modded/refurb'd unit, and two stock that need some service. Both worked fine for several weeks, and then both developed the same symptom: reduced output in one channel. I also had a prior modded/refurb'd unit, since sold. All have stiff tuning. Yes, even though quite handsome, with above-average sensitivity and killer sound, IMO, the ergonomics of these are certainly lacking a bit." Our contributor Robert said, "I have a peeve with my Citation 18. I haven't counted and written down *exactly* how many times it's necessary to 'thumb' the tuning wheel to change from 88.1 to 107.9 MHz (my two favorite stations), but I'm thinking it's about 25-30 times, which seems ridiculous." Our contributor Dante replied, "On every one I've tried, the tuning feels 'damped.' I still have a couple and if try to spin the tuning wheel hard to coast down the dial, it won't. Whether or not by design, I don't know, but it is consistent among different units." Read our panelist JohnC's mod and recap recipe for the Citation 18 on our DIY Mods page. Sale prices for the Citation 18 on eBay have risen over the past few years as praise for its performance and moddability has continued in our FMtuners group. Anything from $178 (in 6/07) to $570 or $588 (in 1/07) is possible, but $250-300 is probably a good price.
Harman/Kardon Citation 23 (1987, $700/orig $595, front, back, with preamp, specs/alignment guide, circuit description/block diagram,
main board showing adjustment points, Audio review, Stereo Review review)
One of the first digital "super tuners" for DXers, the Citation 23 claimed 30 dB of adjacent channel selectivity but Stereo Review's review sample was measured at 46 dB. The Citation 23 does not have a wide/narrow IF bandwidth selector, instead using a fine-tuning ("Hi Q") circuit that allows one to tune slightly away from the center of the channel and away from an interfering adjacent channel station. The Citation 23 has 5 ceramic filters, 3 blue ML GDT type which are used in the wide IF bandwidth setting and two blue MZ GDT type which are used in the "active tracking" ("Hi Q") mode. Our contributor David Rich notes that the Citation 23 is double-tuned at the antenna and double-tuned after the RF amp. A contributor who obtained many "refurbished" Citation 23s direct from HK found that even after going through their "factory repair facility," quality control was lacking. The tuner's sound varied significantly from unit to unit, with some sounding "pretty good to 'barrel chested' while others were flat out 'muddy'."
Our contributor Bill T. found no detectable difference in the sound of the two Citation 23s that he owned, and thinks it's "simply a well-rounded performer." But our contributor Hilary says: "Your item on the Citation 23 requested that someone write in with a ceramic filter count. I have the book and it shows three of them in the signal path, with another path coming off from a point between the second and third filters. This path has two more filters in it and goes to a phase comparator in the 'active tracking circuit.' But it probably doesn't matter because you shouldn't buy one. Construction quality is one step below junk, and it's particularly shameful because the tuner is pretty elaborately designed, looks very nice and sounds really great. All of that thoughtful, dare I say heartfelt, design work went straight into the trash because some bastard decided to have these built in the cheapest way humanly possible."
Our contributor John V. says, "Hard to use. The fine-tuning feature kinda sucks 'cause you have to use that digital output meter which is not very sensitive. It is forward, almost having an EQ type midrange/upper/midrange push boost. In other words, it sounds like early CDs and CD players. Then the display itself is not bright enough and all the other controls are difficult to use and see. It's a disappointment. The Carver TX-11 kills it sonically [ouch - Editor]. The Citation is sensitive enough, but with its mute defeat, you're not really defeating the mute till you actually stop tuning. If the signal is at 90.3, you can defeat the mute and go to 90.5, but the mute comes on for that moment you're tuning the knob." And our contributor John Byrns adds, "The 'active tracking' circuit appears to be nothing more than an ordinary PLL detector. The Citation 23 appears to use ordinary wide and narrow IF strips, with the wide IF using a quadrature detector and the narrow IF using a PLL detector. The only odd thing is that in the narrow mode, rather than taking the demodulated signal directly from the PLL, the output of the PLL VCO is fed into the narrow IF's quadrature detector circuit and demodulated there for a second time. I assume that the reason for this is to simplify the circuits for switching between the wide and narrow modes, and possibly to allow for making some sort of unique advertising claims."
Our contributor Greg gives us a detailed review of the circuit: "Judging from the circuit description and the schematic, it appears that the 23 does have two unusual features. The first is the use of a phase-locked loop to track the actual 10.7 MHz IF signal and deliver this 'reconstructed' signal to the detector. In the normal wide IF mode, the tuner is pretty conventional with no use of the PLL in the IF. But in the 'Hi-Q' mode, the PLL in the IF is fed a signal through two additional ceramic filters which already narrows the IF bandwidth to improve selectivity. The PLL allows further discrimination between the desired IF frequency and any signal from an interfering adjacent station by limiting the deviation lock range of the PLL to just over the 75 kHz limit that represents 100% modulation. Any attempt to range beyond that limit results in the PLL not tracking the signal, which means that any interfering adjacent IF signals would have a tough time capturing the PLL as it tracks the desired signal. This amounts to an increase in adjacent channel selectivity.
"I'm not sure of the full function of the LA1235 chip IC202, but it is apparently a complete PLL with its own voltage-controlled oscillator. The control voltage required to keep the PLL in phase lock is actually the demodulated audio from the incoming IF signal, but this signal is not what passes directly on to the tuner's audio output. Apparently, this control voltage is used to modulate a second VCO composed of Q206, L203 and varactor diode D203. It's the output of this discrete VCO which has a nominal unmodulated frequency of 10.7 MHz that is fed back into the quadrature detector which then becomes the audio output from the tuner. The second unusual feature of the tuner is the 'fine tuning' control which is a way of allowing a digital frequency-synthesized tuner to be deliberately tuned slightly off the center frequency of the desired station. This can reduce the interference from an adjacent channel and is easily done in an analog tuner by slight misadjustment of the tuning control, but it is not normally allowed in a synthesized tuner. The fine tuning feature of this tuner deliberately allows a small amount of DC voltage, controlled by the fine tuning knob, to be added to the discrete VCO control voltage that allows the VCO to be deliberately shifted a bit higher or lower which shifts the IF frequency slightly off the 10.7 MHz center as a way of reducing the amount of adjacent channel interference."
Our panelist Bob has used two Citation 23s and reports: "It has a 5-gang front end, but an unconventional RF front end box with no 'usual' cap adjustments. The gang inductors are copper air coils, with 'bend the wire' adjustments done at the factory. The service manual has no instructions at all for adjusting them. Despite these issues, the sensitivity is fairly good, better than the Sony ST-S730ES, and as good as most digital tuners except for a few really outstanding models. Be forewarned, the active tracking on both units was grossly off as received, but still *sorta* worked. After adjustments, the active tracking seems fairly effective, but adjustment is tricky. It is roughly as good as, but no better than, the Yamaha TX-1000 in narrow mode with .01 MHz fine tuning. How the active tracking works is pretty amazing: a second varactor-tuned oscillator is driven by a phase-locked loop to recreate the IF signal, free of local interference. The controls allow for mono/stereo operation, but no MPX blend control. Tuning is done in 0.1 MHz increments. The Citation 23 came standard with a remote control. Overall build quality on these units, compared to other top-of-the-line, expensive digital tuners from Kenwood, Pioneer, Rotel or Yamaha, is a bit below the mark. But overall, the sound and reception after alignment seem very good.
"To modify the filters or audio caps, you need to remove the circuit board, which means removing about a dozen cables and the rear connections. Common mods include replacement of four audio path caps, removal of the internal 300-ohm balun, and socketing the filters. In my unit, the first wide filter appears to have a circuit mismatch, likely incorrect drive direct from the IF transformer. The wide stereo distortion would not go below 0.2% until the first filter was replaced with a 0.1 µF cap, and then it dropped like a rock to 0.02%. Selectivity with only two ML filters in wide is fine with a rotating antenna. Active tracking stereo distortion was lower than normal for such a selective narrow circuit, at about 0.15%. With the stock discrete transistor output stage after the LA3401 MPX chip, four new Black Gate caps, and the filter mod above, the Citation 23 now sounds very good indeed. For the current price (low $100s) [now generally lower - Editor], I'd say it is a good budget bargain for audiophiles who need a remote control and can do some of these mods to improve the sound."
Here's a 2020 update from Bob, with some reiteration and some new info: "The Citation 23 had an expensive list price but was not built super-expensive inside even though it was made in Japan. By that point in time, the Citation series was not made to the same standard as earlier Citation units. The 22 and 24 amps had a decent design but, like the 23, were made to typical standards, not the previous Citation series standards. The smallish closed-box Mitsumi RF front end has no trim cap adjustments, and uses inexpensive horizontal coil wire inductors versus vertical coils with ferrite adjustment cores that were seen in almost all great tuners.
"If you straighten out the bad examples, they are great units. It just seems like the quality control was all over the place, and some units were very good and some bad in terms of components used and adjustment. I certainly like the Citation 23 after a few simple mods, but would not pay as much as I would for a Yamaha T-85 or TX-1000, or Rotel RT-990BX. Those other models were sold in the same highish list price area, but were designed and built well. They are worth paying hundreds of $ for now, but not the 23. But I feel the 23 is good deal under $100 with the remote, which may be the highlight of this tuner. The 23's remote lets you control power, mono/stereo, mute and seek, and select 16 presets. It also allows up/down tuning in 0.1 MHz increments (or fast if you hold the remote button down) and switching between FM/AM, which I never use. If you need a good inexpensive tuner with remote, it's a choice to include in your searches." The Citation 23 is not uncommon on eBay and usually sells for just $50-80, with a low and high of $26 in 3/09 and $175 in 1/09.
Harman/Kardon HK500 (photo, back, inside)
Just to be clear... just because we list a tuner here doesn't mean it's a good buy. The HK500 is attractive but, as our contributor Don W. observes, "it was at or near the bottom of the HK line in its day. It does have separate variable and fixed outputs, but no detector output that could be used for an external MPX decoder. I can't see it being an unknown giant killer." Our contributor Peter W. corroborates this: "I had one of these beasts - and, for the record, the only tuner that was substantially less sensitive (but not less selective) was my Dynaco FM3. The HK500 did not last long in the collection. It is a pretty little thing, however, and shares some familial characteristics with the Citation 18." With 3 FM gangs and 3 ceramic filters, the HK500 will be outperformed by other HK tuners that can be bought for $30 or less, so don't overpay for this one.
Harman/Kardon T403 (photo, owner's manual)
Our contributor Gary says his T403 was a "pleasant surprise": "It is heavy and solidly built and impresses me with how good it sounds in stereo. It's very quiet with no audible hiss in stereo mode, even with less than meter-pegging signals. It replaced the Technics ST-8077 in my main system." Our contributor Ron W. adds, "I've had my T403 for years. It may not be 'high performance,' but it sounds great. One of the most natural-sounding tuners I've heard." The T403's front panel has only an AM/FM/FM Stereo switch, muting switch and rather cheesy signal-strength meter, but the back panel has an MPX detector output jack and fixed and variable RCA outputs. As can be seen on the last page of the owner's manual, the T403 has truly terrible specs for selectivity, capture ratio and image rejection, among other things, so we wouldn't recommend that anyone pay more than $10-20 for one.
Harman/Kardon TU615 (1981, $350)
The TU615 is an undistinguished but decent digital tuner with 4 gangs and 3 ceramic filters. It had acceptable specs, with the exception of selectivity (so it may be a cheap candidate for filter experimentation). Our panelist Ray says, "It sounds just fine - not outstanding, not bad. I don't have a service manual, but a peek under the hood appears to reveal discrete transistor output amps." Ray's TU615 had a de-emphasis time constant in between 50 µS and 75 µS, contributing to his theory that some tuners at the lower end of a brand's line were intentionally given a compromise T.C. so as to be close in both the 50 µS and 75 µS markets. In addition to the TU615, other examples of this that he found are the Fisher FM-2310, Pioneer TX-6200 and Realistic TM-1000. The TU615 usually sells for $30-80 on eBay, with a high of $100 in 8/04 in an auction with only one bidder. We don't know anything about its little brother, the TU610 (1981, $200), which should sell for $30 or less on eBay.
Harman/Kardon TU911 or TU911A (1987,
$299/orig 1986, $235, schematic, technical manual)
Harman/Kardon TU912 (1986,
These digital tuners may be worth a look. Our contributor Marc says, "Someone gave me a TU911 and It took two weeks before I decided to try it. I thought it was a low-fi tuner. This tuner was one of the biggest surprises I've had - good sensitivity and marvelous sound. It's a keeper." However, our contributor Warren says his TU911 "sounded far better than it should have for the money, but I have owned about 20 tuners and the TU911 certainly sat in the lower half of the group." Our contributor Rich tells us that the TU911A was an FM-AM variation of the FM-only TU911. Any of these should be available for $50-60 or less on eBay.
Harman/Kardon TU915 (1984, $450)
The digital TU915 seems like the best of a rather anonymous group of similarly numbered HK tuners. Our panelist Ray "did the Ammons board trick on the TU915, putting 'cap-FET-230 kHz GDT filter' in place of the 280 kHz GDT filter that was CF-201. That makes it a 5-gang, 3-GDT filter unit. That little IF gain stage really perked up its signal snatching/quieting abilities. I'd already done basic cap mods to the power supply and audio chain. I really liked the sound of the discrete outs in the TU915 and now it receives with respectability as well -- another sleeper." Here's an addendum from Ray: "The TU915 is also an outstanding performer on the AM band. It is the most sensitive digitally tuned tuner that I've ever run across. It's rated at only 8 µV using an external antenna and for that I use a tuneable loop set indoors alongside the tuner, replacing the little plastic AM fixed loop." The TU915 usually sells for $50-90 on eBay, with a low of $25 in 2/07.
Our contributor Radu adds: "I am in full agreement with Ray that this tuner is a sleeper. It sounds great, with a wide soundstage, above-average reception, and very good extension at both extremes of the audio frequency range. Very quiet background/noise (though take good note of the measurements below). I listened to this unmodified (unaligned, nothing done to it by me) and kept staring at my rack to see if I didn't accidentally hook up a different tuner (one of my good ones). So this is not an alignment story, but a gem, a sleeper tuner story.
"Now onto the circuit (note that HiFi Engine has the service manual). It has the equivalent of 5 gangs - 2 tuned circuits before the RF amp (a MOSFET), and 2 after. The mixer is also a MOSFET. A single bandwidth IF lines 3 ceramic filters - Murata ML types (280 kHz GDT), so excellent quality - followed by a quadrature detector based on the HA11225. The stereo demultiplexer is an PLL type based on the (obscure, to me) BA1330. Given the distortion and separation numbers (see below), it does a great job. There's an SCA filter ("SCA CANCEL CIRCUIT"), but I'm unsure of its effect on things unwanted in the output, such as pilot or IBOC noise. The 19 kHz presence is not negligible. Muting is done with NAND gates - something a bit novel to me, but maybe commonplace in the newer tuners (I'm of the vintage mind).
"Construction. The tuner is pretty tightly put together - one board (which I don't typically like a whole lot) - and not an empty box by any means. There's just the right amount of space in there - for instance, the power transformer is judiciously placed on the chassis, not the PCB, and as far away as feasible. The construction quality feels good and it's quite a handsome unit. The 8 presets are tiny, lit buttons, but feel solid and there's a satisfying feel to actuating them. Tuning is quick and confident - no unexpected hesitations or skips - and the unit is simple in aspect and controls in a good, clean way. Also a positive is that it's a full-size component, in both width and depth (why did Nikko make the Gamma I so packed and hard to work in?... and half depth!). There are 300-ohm and 75-ohm antenna inputs, fixed and variable outputs (variable is controlled by a pot on the back - no knob, but it's ruggedized and easy to adjust by hand from the front, reaching to the back). Note that muting level is adjustable from the front panel, and there's also a "high blend" switch which is pretty effective and unobtrusive.
"Now on to measurements. To be sure, this is a unit I have not touched - no recapping, no aligning, and no upgrades at all. Per HiFi Engine, the unit was in production around 1985-86, so it has a respectable age both regarding going out of alignment, and needing new electrolytics. And yet, it measures very well, and largely within spec (with the reserve of specs being a bit cryptic and missing some typical data). I include spectrum for both channels, and frequency response with de-emphasis applied. THD is 0.033/0.037% L/R (0.06% nominal values in the specs) - admittedly, pretty awesome - while THD+N is in the mid-50s dBs (this number needs a few grains of salt, as the pilot is pretty heavy in there and other things may factor in; I surely can't hear all that noise - in fact, overall, it competes among the quietest tuners in my rack). I am personally unsure of the true state of filtering on this one - thinking of pilot mostly, though SCA filtering exists - so factor that into your interpreting of THD+N values. Moving on, crosstalk is a couple of dBs better than 50 dB either way I measured (L->R; R->L). This is a bit short of nominal spec, though still within the spec limit. Frequency response, which I can't find in the specs, is well within 1.5 dB from 20 Hz to 15 kHz. If you look at the graphs and think there's both a Himalaya and a Mariana Trench in there, note that the whole thing is within +2 dB and -2 dB, so the true response is very flat. In terms of sensitivity, I am getting a reading in the 0.8 µV value which is exceptionally good, in my (limited) experience - but this is pretty much what I'm hearing from the unit as well.
"All in all, very complimenting measurements, really good reception, and great sound. Highly recommended for the sparrow feed this seems to go for, and well more (it dented me by about $20). Also, most of my tuners (and environment!) are analog and I came to appreciate being able to jump from one preset to another, especially if I don't need to trade much on the sound quality aspect."
Our contributor Marc adds, "Great sensitivity, discrete output stage and there's not a lot of caps in the audio signal path. A recap job should be done because H-K used bad caps in these. With upgrades and a good alignment, this tuner is now my favorite for sound quality."
Harman/Kardon TU920 (1987, $400, schematic,
main board, technical manual)
The digital TU920 is another tuner that stands out from HK's confusing lineup of similarly numbered tuners. It has an "active tracking" circuit and appears to be the little brother of the Citation 23. Our panelist Bob notes that the two tuners are very similar inside based on their schematics. DXer Mike Bugaj has a review of the TU920 on his website. The TU920 usually sells for $45-100 on eBay.
Harvey Radio Labs 193R Model 47 (1947, front, inside)
Here's Mike Zuccaro's review of this very rare tube receiver:
Harvey Radio Labs was similar to REL. This monster 17-tube, dual conversion high fidelity FM receiver was perhaps the first FM broadcast monitor. It had a frequency range of 85-115 MHz, and was a redesign of the earlier 44-50 mc model. This is a great-sounding rack-mount unit that weighs a ton and makes the REL Precedent and Marantz 10B look flimsy by comparison. It has several interesting features, including an antenna tuning control, a two-position "mute" switch (not variable), and lots of negative feedback used in the audio stage. It has two meters, one for signal strength (50 uA) and one for center of station.
A type 956 acorn tube is the RF amplifier, followed by a 9002 local oscillator. Plate voltage to the L.O. is supplied by a VR-150 regulator. The tuner uses ceramic tube sockets and a massive tuning cap. The L.O. runs 10.7 MHz below the incoming RF, and a 6AK5 mixer tube then converts it to the first IF of 10.7 MHz. This is then mixed again, via a 6K8 pentagrid converter with a 6.1 MHz crystal oscillator. The difference is 4.5 MHz, which is then amplified by two stages of double-tuned IF transformers, driven by two 6AB7 tubes, and then fed to two more tuned 6AC7 limiters.
A 6h6 discriminator is used, presumably Foster-Seely. Another 6H6 tube is used for the muting/squelch. The demodulated audio is fed to a 6AC7 voltage amplifier, through the bass and treble controls, followed by a 6SL7, 6SJ7, a 6J5 phase splitter to a pair of push-pull 6V6's. A large UTC output transformer is used, and can be strapped to drive an 8 ohm speaker. The unit also has a phono input. A 5U4 rectifier tube is used.
I've never seen another one other than mine. If anyone has a schematic or manual for this unit, please contact me! There's more information on Harvey products here.
Heathkit AJ-1510 (1972, front, tuning closeup, back, inside, top 1, 2, ad, Audio magazine review)
Here's Mike Zuccaro's review:
"The Heathkit AJ-1510, the first digital frequency synthesized tuner, was a true synthesizer tuner and not an analog tuner with a counter. Input was by means of a keyboard, auto-scanning, or 3 punch cards, and the tuner had no memory except for the punch cards. The AJ-1510's frequency readout was via incandescent RCA Numitron displays, which are now hard to find and pricey but can be easily replaced, if desired, with modern 7-segment LED displays. The AJ-1510 had a walnut cover and a preassembled and aligned front end. The IF section had sealed LC filters - two 5-pole filters in two separate cans, made by Filtech (which also supplied filters to SAE and a few other American companies). The tuner used a pulse counter detector and had very low distortion. It had 2 FET RF amps and a FET mixer, a bipolar oscillator stage and a bipolar buffer transistor to drive the PLL. I don't know who made the front end, but it was not built by Heath. Under the front drop-down panel are controls for auto-sweep speed, noise squelch, AGC squelch, signal/multipath switch and stereo/mono, and slots for the punch cards.
"I believe the AJ-1510 was the first digital synthesizer product anywhere in the Heath line (no earlier ham products or TVs used direct digital entry). All of tuner's circuits were on plug-in boards, with an extender card supplied. A pre-production engineering prototype of the AJ-1510 was very well reviewed in the May 1972 issue of Audio. There was also an article in the May 1973 issue of Popular Electronics by Heath engineer Dave Thomas, which is basically just a transcript of the circuit description from the assembly manual. The tuner was manufactured until about 1975. It shows up occasionally on eBay, but don't buy one if you can't fix it yourself - the AJ-1510 is not a unit for tweakers, hobbyists or beginners."
Brent Hilpert's website has a great page on the AJ-1510, with lots of nice closeup photos, and plenty more interesting stuff on early digital electronics. Our contributor Mark H. tells us: "Along the way, Heathkit came out with an 'a' version of this tuner, the AJ-1510A. I asked Heath about this and here is their reply from Leon Cray, Technical Consultant, on 5/1/80: 'There have been no engineering changes made to the AJ-1510 digital tuner. The model AJ-1510A was introduced when one of the parts, IC606, on the IF circuit board was no longer available from the manufacturer and had to be replaced with discrete components. Although this did require a new IF circuit board, it did not result in an increase in the performance of the unit.'" Our contributor Ron says, "The AJ-1510A is the only Heathkit product I have seen where there were discrepancies between the circuit and the schematic. The grounding is bad and the lack of proper bypassing (one board has no decoupling at all) is substandard engineering. But fixing these problems is rewarding, although the tuner has a distinctive sound to it and cannot really be considered high fidelity in its original form. They fumbled away the chance to design a really great tuner here, but I have tried a few mods that make it much more acceptable."
The AJ-1510 usually sells for $100-165 on eBay, with a low of $82 in 6/06 and a high of $283 in 2/07, and an unbuilt kit went for an astounding $2,276 in 4/03. The apparently similar AJ-1510A (front, back, schematics 1, 2, assembly manual 1, 2) usually sells for about the same prices, but one went for an impressive $431 in 1/05. A contributor tells us that the AJ-1510A's circuit board contacts were gold-plated, while those in the AJ-1510 were not.
Heathkit AJ-1600 (1979, front 1, 2, back, inside 1, 2, ad, schematic, parts)
Here's a review from Bill Ammons: "The AJ-1600 is a black-faced rack-mount unit with handles. The front end is a 5-gang ALPS with two RF MOSFETs and a MOSFET mixer. This was ALPS' top-of-the-line front end module. This is an analog tuner with a digital frequency display that uses the local oscillator as a frequency source. It has dual IF bandwidths with two standard 280 kHz 3-pin filters in the Wide mode. The Wide mode feeds the Narrow mode which has two of the older 4-pin MJA filters. There is plenty of IF gain and limiting before the ratio detector. The AJ-1600 uses a HA11223 decoder IC and has discreet audio outputs. I was only able to get about 40 dB of stereo separation stock from this one. By changing out the old Wide filters to SFELA10.7FALLs and re-scaling the composite low-pass filter component values, I am now getting closer to 50 dB, with 0.15% distortion in stereo. It is a very sensitive unit, with very good 400 kHz selectivity. When modified to use 4 standard 3-pin filters in Narrow, this tuner can be made very selective, similar to a modified Kenwood KT-7500. The AJ-1600 is very easy to service and modify because all of the PCBs are on connectors."
Our contributor Pete adds, "Good sound and good performance. I was hoping that it had green LED readouts, but it turned out to be a fluorescent display -- not bad, but not my preference. AM broadcast performance was sensitive, but the IF bandwidth was pretty broad. Stock, the tuner uses Murata CFU455E filters, which have a 15 kHz bandwidth. I replaced them with a pair of CFU455H filters, which have a 6 kHz bandwidth. AM performance is similar to a McIntosh MR 74 now, which is fairly respectable." Our contributor doug s. says, "Excellent sound and reception, and with mods, it is about as good as anything out there, IMO." The AJ-1600 usually sells for $120-250 on eBay, with a low of $81 in 9/08, but nice ones with wooden cabinets can go for over $300 ($370 in 3/07, $305 in 12/09).
Hitachi FT-007 (photo, left closeup, right closeup)
The FT-007 is a very compact, digital synthesizer FM-AM tuner with elegant rosewood sides. It has a 5-varactor front end (equivalent to 5 gangs) and 4 ceramic filters, and is packed with nice features including pushbuttons for Wide and Narrow IF bandwidth settings, RF band ("double/single"), signal strength readout in dBs, and 16 presets. The FT-007 also has a pushbutton to engage Hitachi's "FCCS" (Field Condition Computer System) circuitry, as described in the FT-5500 MKII writeup below, and is fairly selective in stock form. Our panelist Ray compared photos of an FT-007 to his beloved FT-5500 MKII and says, "The circuit board of the FT-007 appears barren as it has lots of open spaces. The IF sections appear to be the same and I find no componentry in the FT-007 suggesting an output buffer nor discrete audio amps. I could not read the numbers on many of the IC's but some appear to be NON-Hitachi!! Bottom line, I do not think the FT-007 is the 'mother
of all Hitachi tuners' but rather a restyled and cost-reduced version of the FT-5500 MKII."
Then Ray had a chance to see the FT-007 in person: "Thanks to the generosity of some of our members, RFM finally got his mitts on an FT-007 to study, test and play with. The grand finale was a shootout with his modded FT-5500 MKII. The two tuners involved in this shootout have some previous TIC recognition. The FT-007 was the subject of Jim's Shootout #79 and the FT-5500 MKII was reviewed in Jim's Modified Tuner Report of 06/12/05. The FT-007 is a later Hitachi release than the FT-5500 MKII but has virtually all the same performance features. Much of it seems to be contained in larger scale ICs and thus it is a smaller and lighter package. The RF and IF stages are near identical, but the FT-007 uses an LA1265 detector/IF IC where the FT-5500 MKII uses an older LA1235. The same MPX chip is used and the audio output sections are almost part-for-part the same. The FT-007 has shorter and better PC runs, however. In the DX arena I could detect no difference between them, as both are exemplary. They both have the same dBµV digital signal strength meters but the FT-007's read consistently 10 dBµV higher. As Bob says, 'a mere pot tweak apart.' Quieting performance seemed the same for both.
On the test bench the FT-007 showed a very flat frequency response of +/- 0.4 dB from 20 Hz to 15 kHz. I did see very minor crossover notch distortion which I cannot explain since the MPX IC runs single polarity. I have never noticed this in a tuner before. In Ray's Room they shared a splitter and were A/B'd for sonic differences. This was very tough and my findings amount to mainly 'piddling differences.' The challenge was made more difficult as the FT-5500 MKII has a higher output level, so adjustment had to be continually made. However, the modded FT-5500 MKII sounds better. It has a more robust lower midrange, giving more realistic body to the music. They both have plenty of bass presentation. With multiple vocalists there is a realistic separation between them with the FT-5500 MKII. Both give a wide image but that elusive third dimension seems more pronounced with the modded FT-5500 MKII. I do think the FT-007 would better the sound of a stock FT-5500 MKII but that's stretching the imaginative audio memory a bit much for RFM. If forced to choose between them in stock form, I think I'd take the FT-007 (sorry old pal, but that's why I stuck that hot iron into your innards back when)." The FT-007 is very rare and only a few have been seen on eBay over the past several years. They usually sell for $75-100 but one went for a stunning $205 in 6/09.
Hitachi FT-920 (1977, $300)
Our panelist Ray reports: "RFM has obtained an FT-920 to check out and play with... yes, and modify. The first look under the hood of the stock unit found 4 FM gangs and 3 AM gangs. The single-bandwidth FM IF string contains 3 ceramic filters: a 280 out of the mixer, then an HA1211 IC amp followed by 2 more 280s, and then into the HA1137 detector IC. There's a single transistor gain stage between the detector and the HA1156W MPX IC but no low-pass filtering nor notches. The output of the MPX feeds another transistor gain stage, pilot notches and a discreet output amp. Nothing fancy, just good, solid design using the components of the day. Measured de-emphasis time constant was 69.9 µS and frequency response was -0.55 dB to +0.35 dB from 40 Hz to 12 kHz. It was down 0.95 dB at 15 kHz and 2.3 dB at 20 Hz... not bad. Having paid $24.50 for it, RFM finds this tuner to be fine sparrow feed and, with its fully removable bottom panel, it will be easy to upgrade." And indeed, with a couple dozen new caps and a Bill Ammons Filter Adder PCB installed, this particular FT-920 now sits proudly under our panelist Eric's matching HA-610 amp (thanks Ray!). Our contributor Thrassyvoulos adds, "Sonically, the FT-920 is a true bargain, but compared to the FT-5500 MKII it clearly loses in the realms of sensitivity and selectivity, though it's not bad." The FT-920 can sell for anywhere from $24-75 on eBay, with a high of $100 in 12/08.
Hitachi FT-3500 (1981, $170)
The FT-3500 is a basic slimline FM/AM tuner with "vector tuning system," whatever that means. We wouldn't necessarily go crazy looking for one but our contributor Chris C. seems to like his: "I have a little FT-3500 as my current office tuner. It has 3 gangs on FM, 2 on AM. There are two chips visible: AN217P, which appears to be the AM RF-IF chip, and an HA 12412, which is the FM IF amp/detector/meter amp/etc. chip. Hitachi makes its data sheet available for that (thank you, Hitachi). But I didn't see an IC for the MPX. Discrete components in the Hitachi tuners? This little low-end tuner seems surprisingly sensitive in my poor-signal office environment. It does at least as well as its predecessors, the Sansui TU-317 and an old H-K 430 receiver. It sounds pretty good, too, although it's not a critical listening setup here." The FT-3500 should be findable for $20 or less on eBay.
Hitachi FT-4400 (1980, $250)
The FT-4400 was third from the top of Hitachi's line, below the FT-8000 and FT-5000. According to our panelist Bob, "It has 4 gangs and .08% distortion, 50 dB separation, so not bottom-of-the-line performance. The audio specs are different from the FT-8000 and FT-5000, which oddly were both slightly worse in distortion. Perhaps they had more narrow single IF filters. The FT-4400 somewhat reminds one of the FT-8000 with the round tuning buttons. Worth checking out. No narrow IF mode, though, so may not be a great unit for weak or adjacent signals." The FT-4400 usually sells for $20-30 on eBay, with lows of $4 in 9/06 and $1.00 in 8/10.
Hitachi FT-5000 (1979, $300, photo)
Our panelist Ray offers this review: "The FT-5000 was an early fully digital tuner. Its service manual is dated September 1979. Its circuit features and ICs seem pretty typical of the midrange tuners from many manufacturers through the '80s. It has 4 varactor 'gangs' and 3 280 kHz IF filters, and a single dual-gate FET RF amp with AGC and PLL in the MPX section. One giveaway of its vintage is the use of three AA cells for memory backup. The FT-5000 uses the HA1196 for MPX and unbuffered audio out. The de-emphasis, via feedback, seems spot-on at 75 µS and the output is very clean, i.e., no visible pilot signals riding along. Some specs: IHF sensitivity 1.0 µV @ 75 ohm; THD .20% IHF, stereo; S/N ratio 73 dB mono and 68 dB stereo; alternate channel selectivity 70 dB IHF; capture ratio 1.0 dB; stereo separation 48 dB. Subjectively, it sounds quite good and has excellent quieting. One-on-one, it easily bests my similarly equipped HK TU615 in both RF and audio performance. BUT, it ain't no FT-5500MKII! I'd call the FT-5000 a good value at less than $40, IMHO." And as luck would have it, the FT-5000 can indeed be found for $20-30 on eBay.
Hitachi FT-5500 MKII (1984, $350, photo, different face, service manual, Hi-Fi News review, Hi-Fi Answers review, New Hi-Fi Sound review)
Somewhat scarce in the U.S., our panelist Ray's favorite is a solidly built, low-profile, black digital tuner with some unusual and nice features. In the mid-1980s, the FT-5500 MKII was highly regarded by the European audio press, but received little recognition in the U.S. Its front end consists of 5 varactors (equivalent to 5 gangs) for FM, in a sealed module that isn't represented in detail on the schematic, and 2 for AM. The FT-5500 MKII has a wide/narrow selector that changes the bandwidth for both FM and AM. The IF section in Wide mode has 2 ceramic filters around a group delay circuit and 2 gain stages. In Narrow mode, the group delay circuit is bypassed by 2 more ceramic filters, for a total of 4 filters in Narrow. [More on the filters below.] The FT-5500 MKII's "FCCS" (Field Condition Computer System) appears to be similar to Onkyo's "APR" system. When the FCCS push-button is selected, the tuner auto-scans 2.5 MHz up and down the band from the tuned frequency to assess the potential interference and signal strength, and then selects the optimum RF and IF settings. These can be manually overridden, but the computer seems to always get it right. Stations' FCCS settings can also be stored in each of the 16 memory preset settings. One (not uncommon) shortcoming is that the muting switch and stereo/mono are on the same button, which prevents one from choosing to listen in stereo to stations with signal strength below the muting threshold. The digital signal-strength indicator has exceptional range, 10 to 80 dB microvolt, which equates to 21 to 91 dBf (add eleven to the display). The FT-5500 MKII also has an auto quieting control (a blend circuit) and recording calibration tone button.
Ray found that his stock sample, in a side-by-side comparison to a stock Kenwood KT-7550, was better at quieting weak signals and sounded much better. The FT-5500 MKII also outperformed the KT-7550 on AM. Ray says that he has had several other tuners, including a Pioneer TX-9800, and prefers the Hitachi overall. Ray did some mods to his FT-5500 MKII as can be seen here. He changed where the the de-emphasis is done. Stock, it was in the feedback loop of the op-amp (built into the MPX chip). He added a new op-amp output stage, and added the RC components to implement the de-emphasis in a passive filter. See the Modified Tuner Report for our panelist Jim's reviews of Ray's two mod attempts, and see Ray's report on a shootout between his modded FT-5500 MKII and a stock Hitachi FT-007 in the above writeup for the latter tuner. Ray's comparison of his FT-5500 MKII to a Carver TX-11b can be found in the Carver writeup, and Ray and our panelist JohnC briefly compare their respective modded 5500s to the Sony ST-J75 and Denon TU-660 in our writeup of the latter tuner. Read our panelist Bob's impressions of Ray's tuner, post-mods, in our FMtuners group.
Our panelist Eric found that Ray's FT-5500 MKII had excellent selectivity in Narrow mode, with good quieting on weak stations adjacent to stronger locals. Our contributors Tim and Ann chime in: "We've been putting our recently acquired FT-5500 MKII through its paces and Ray is on to something, IOHO. It's a damn fine tuner. It's closer to having that McIntosh 'house' sound than any non-McIntosh tuner we've listened to here. It does not have as much 3-D depth as some tuners we've listened to, but it does have a very, very good midrange, the bass is phenomenal, and the highs are good as well. And the built-in digital signal strength meter calibrated in dBs is just as accurate, we've found, as using a scope to help aim our antenna, and it's a whole lot better than trying to use a standard signal strength meter like so many tuners use. It is the most sensitive tuner and best DXer we've tried here." And after an extensive listening test involving their stock FT-5500 MKII, Ray's modded one, and a McIntosh MR 74, Tim says he "wouldn't kick the Hitachi out of bed for eating crackers!"
Our contributor Mike M. analyzed the mysterious Murata SFD10.7A filter used in the FT-5500 MKII [thanks to our contributor Ed K. for the catalog clip]: "The SFD10.7A filter is a discriminator for use with the FM detector, for this part the CA3089A quadrature detector. It is used as the second IF filter in the Wide mode or the fourth IF filter in Narrow mode. The Hitachi engineers appear to have put a lot of thought into obtaining the flattest G.D.T. with this tuner in both circuit design and filter selection. For Wide, they strung together a SFE10.7ML filter (chosen for flat GDT, 280 kHz), a GDT compensation circuit to 'reverse' the GDT curve of the first filter, described in the service manual, and the above-mentioned SFD10.7A discriminator which acts like a very wide filter with extremely flat GDT. For Narrow (switched in place of the GDT compensation circuit), they used a SFE10.7MZa filter (blue body, flat GDT, low distortion, 180 kHz) and a SFE10.7MS 3 filter (tan body, 180 kHz). The clever thing about the combination of filters in the narrow circuit is that the shapes of the GDT delay curves offset each other. The MS filter curves upward and the MZ curves downward over frequency, which results in a flattening effect of GDT rather than the reverse. Strange usage of a discriminator as an IF filter, or perhaps inspired. Can't argue with the tuner's distortion performance without having to resort to fancy distortion cancellation circuitry."
But wait, here's more from Mike: "Changing filters in the Hitachi FT-5500MkII this month really showed me how important the filter GDT curves are to tuner THD. The tuner has 4 IF filters and each of them is a different series, including the last which I believe it a discriminator, not a filter. Even changing the first filter from a type ML to MX produced a large reduction in distortion in Wide (from 0.048% to 0.027%) with only about a dB loss in Mono Usable Sensitivity. At 50 dB quieting sensitivity levels, there was no change in performance."
The FT-5500 MKII usually sells for $70-125 on eBay, while the more common FT-5500 (1981, $350, photo, usually just $15-50 on eBay, is believed to be somewhat similar. Ray says, "The FT-5500 was the ground-breaker with the initial release of the FCCS technology. The MKII has different pilot tone cancellation to reduce HF audio garbage. Also, the MKII's memory presets include the FCCS RF and IF settings, and the front end was revised to include use of GaAs FETs. The MKII has improved pilot filtering and is more resistant to out-of-band RF noise."
Hitachi FT-8000 (1979, $460, photo, large
files: block diagram, schematic 1, schematic 2, schematic 3)
We'll have some basic factual information on this very rare tuner eventually. Our contributor Thomas calls the FT-8000 one of the best-sounding digital tuners he has heard, and prefers it to the underrated FT-5500 MKII. Our contributor Noel says, "I have used an FT-8000 in a third system and have always been very impressed with its ability to pull in stations in the basement with just a wire. But I got another one for $30 on eBay with a beat-up case and for grins I hooked it up in one of my two reference systems. It is substantially better sonically than the Pioneer F-93 I just disconnected. Very natural mids and highs, and very articulate bass. Voices have a way of naturally jumping out in the room. An exceptional solid-state tuner on the cheap." To illustrate the potential variability of different samples of the same tuner, our contributor Dana says that his FT-8000 had "solid bass and a relatively nice soundstage, but I found the overall presentation quite dry and lifeless to my ears, versus equally priced analog units from Kenwood or Sansui." But our contributor doug s. replied: "I think it's excellent sound for the money. It is right there with the Tandberg 3001As I used to own; I didn't experience any of the dryness Dana talks about." Our panelist Ray reviewed the FT-8000's schematic and believes that it's basically an FT-5000 with the addition of an audio output buffer. Here's the
Japanese version of the FT-8000, courtesy of k-nisi's site. The FT-8000 usually sells for $60-100 on eBay, with highs of $200 and $169 in 10/06.
JVC FX-1010TN (1989, $480, photo, brochure)
Our contributor Greg reports: "This tuner was the replacement for the FX-1100BK. The FX-1010 is one of a handful of tuners that use the ultra-low distortion Sanyo LA3450 multiplex decoder. The tuner uses JVC's 'OPTICALINK digital tuning system' which is not just a gimmick. There is a large, dedicated OPTICALINK board inside the tuner with many ICs, resistors, transistors, and caps. Quoting from the service manual, 'In the digital tuning system employed by this unit, an optical transmission system is used between the tuner circuit and the logic circuit, to prevent noise from the logic section from being introduced into the tuner system.' The block diagram of the OPTICALINK system reveals several photocouplers and an A/D converter, among other components. The FX-1010 uses a total of 6 ceramic filters, but only 4 affect the selectivity. Wide mode uses CF201 and CF202, and Narrow mode adds CF203 and CF204. The other two ceramic filters (CF601 and CF602) appear to feed the A/D converter in the OPTICALINK system. The 'TN' designation refers to the titanium color finish that JVC used in the late '80s and early '90s."
Our contributor J.C. says the FX-1010 "has station labeling with 6 alphanumeric characters per station which is an excellent feature ergonomically because you don't have to remember what station are on what frequencies like with most tuners, and there is a button that switches between viewing the label or viewing the signal strength in dB (another nice feature). The other cool thing it does is when you tune using the up/down buttons (not the presets), the display automatically reverts to the signal strength in dB so you can get a good feel for what you are tuning without having to engage the meter manually. That's a nice one some famous tuners don't do (like the Onkyo T-9090 which forces you to push another button every time you want to see signal strength)." The FX-1010TN is rarely seen on eBay and usually sells for $150-260, higher prices than are usually seen for the FX-1100BK.
JVC FX-1100BK(1987, $470, photo, schematic)
Our panelist Bob believes that the FX-1100BK and the FX-1010TN were basically identical except for the color, black (BK) vs. titanium (TN). They did have exactly identical specs and were the same weight. Bob says, "Nice little tuner, 5 gangs, 4 filters. No signal strength bars, just a dB readout on the front panel. One problem: It has muting and stereo/mono on the same switch. But the sound is very, very good, and so is reception sensitivity. Probably a better unit for those with overload problems vs. those who are in the boonies. It does have a MPX blend/quieting circuit that is engaged automatically, called QSC or 'quieting slope circuit.' It lights the 'QSC' on the display when on. The tuner is sensitive as to setup, and as furnished to me was totally off for a DX type. Once you figure out the influence of the three adjustments (muting pot and the two dB display pots), you can set it up to be perfect for weak stereo reception with MPX blend. It works pretty well now, and is fairly sensitive and quiet."
Our contributor Ryan adds that the FX-1100 has a few other nice features as well: dual antenna inputs, an RF attenuator that he says "seems to work better than most," and a very accurate signal strength meter that takes up an incredible amount of board space. Ryan also notes that "in addition to its very well-executed PLL detector, there are also separate distortion adjustments for wide, narrow, and mono which help give this tuner great sound after a careful adjustment." Our contributor doug s. says, "This is a fantastic-sounding tuner that is also quite sensitive. Compares favorably with the much spendier Tandberg 3001A. Soundstage is a hair more forward than that of the Tandberg." doug adds, "though 'ugly,' it's something I could listen to happily ever after, if someone came along and relieved me of all my other tunas. It sounds great, has excellent sensitivity, and a few cool features as well, like measuring signal strength in real time, and being able to set the call letters for the stations being received."
Our contributor Ray D. agrees: "I now understand why doug s. says that if all of his other tuners were taken away, he could live happily with the FX-1100. On mine the bass is not the deepest and the dynamics are bit held back compared to the best I have heard, but the sound is as natural as I have heard, the imaging is solid, and it is very satisfying overall. Reception-wise things are good. The signal level meter in real-time dB is great for fine tuning the antenna and the settings. This is where things get weird.... According to the manual, the Local/DX setting just gives a 20 dB cut to avoid overload. Hardly. It works that way on weak signals around 20 dB or less. If I engage it then, it cuts the signal down as it should. For signals around 40 or 50 dB, engaging the Local might increase the signal by several dB, but sometimes with an increase in noise. Even stranger, I have had two different antennas hooked up giving equal signal strength, but engaging the Local would increase the level of one and reduce the other. Different settings of Wide/Narrow give different results. On strong signals of 70 dB or so, there is no effect at times. Is this some circuit that is far more sophisticated than it claims to be, or is mine just really screwed up? The QSC, a sort of high blend which seems quite effective and not too detrimental to the sound quality, is just as odd. It kicks in automatically and cannot be included on the presets, no manual control possible. On very weak signals it turns on, but on moderate ones where noise is still audible, it does not. I have managed to figure out a few ways to force it. My impression of the FX-1100 is that it is a great tuner designed by people who were not so sharp (I am trying to be kind), if that makes any sense. They should have taken lessons from Akai. The somewhat similarly equipped AT-93 is an ergonomic and functional masterpiece in comparison: lots of functions, lots of automation and manual overrides for everything. Brilliant."
Ray adds, "Some folks complain about the ergonomics of the later digital Yamahas. They obviously never used the FX-1100. I would say its ergonomics are catastrophic. Four different groupings of buttons, to activate the preset scan you must hit two buttons from different groups, you can change the display to signal dB but have to hit the button again every time you change channels, two antenna inputs but no automatic selection, the list just goes on. I am usually not too difficult, but this one is abysmal. Did I mention the low-contrast, small silk screening that I cannot read in low light? But the sound!"
Our contributor Bill C. offers this review and shootout: "The FX-1100 is a tuner where you probably want to have the user manual. There are a number of features that are not immediately intuitive that the manual helps with nicely. I noticed that several commented that the ergonomics are bad, but I won't be that harsh - I didn't have too much trouble with the ergonomics. For initial tests I hooked it up to a cheap Radio Shack rabbit ears TV antenna. I was very impressed with the sound quality. All lights and functions worked perfectly. The tuner is very sensitive and has pretty good selectivity. This is the only tuner I have that employs a dB digital meter for signal-strength readout. I really liked this meter. It made positioning the rabbit ears for optimal reception very, very easy. I also experimented with changing the length of the rabbit ear rods. The dB meter makes finding the optimal length for a given frequency easy. The tuner has 40 presets which I found pretty easy to set. The presets 'remember' most settings such as mono/stereo, wide/narrow, etc. One small quibble: the QSC function, which is JVC's name for the stereo blend feature, is automatically engaged by tuner circuitry - it is not manually controllable from what I could see. The QSC does work well. The local NPR/classical station can be slightly noisy in full stereo, but the JVC engages the QSC with good result. Noise on this station disappears and stereo separation is still quite good.
"Next, I compared the JVC to my Yamaha T-85. These tuners were contemporaries from the 1986-87 period. Both were FM/AM and originally MSRP'ed for around $470-$500. The Yamaha wins easily in the selectivity department, no surprise here. For sensitivity, they are fairly close, with the Yamaha having a slight but not great edge. Sound-wise, they are pretty darn close. Now, both are stock with no recent (if ever) alignment having been done. Both sound good to my ears, nice bass (neither as good as my Nikko Gamma V though), full midrange and clear, natural highs. Build-wise the Yamaha is better, with a heavier gauge metal case. The JVC probably has the thinnest, cheapest case of all my tuners. You could probably dent it with a good poke of your index finger. I popped the case on both. Nice clean layout for both. The Yamaha did have its boards positioned so that there is airspace from the top AND the bottom of the boards. The JVC board rests on the bottom of the case. The Yamaha with better case louvers should breathe better and run cooler. For aethestics, I actually prefer the look of the JVC. It's not a stunning looker, but it's not butt ugly, either. Verdict: If I were buying a tuner new in the late '80s, the T-85 would have been the better buy. Today, for $56, the JVC is big bang for the buck. Today, a T-85 in reasonable shape is going for $150-$250 on eBay. Not bad for the quality tuner it is, but not the outright value the JVC is. As others have noted, this is a tuner I could easily live with to the exclusion of all others."
Our contributor Hank A. adds, "Very natural sonics, love the dB meter for signal strength, just a little light in the bass. Highly recommended." The FX-1100BK usually sells for $70-100 on eBay, with a low of $52 in 8/09 and occasional highs around $150 or even higher.
(1984, photo, inside)
According to our panelist Ray, the T-X900 is "a little brother to the FX-1100BK and FX-1010TN, with less circuit horsepower upfront and out back." Here's Ray's full report: "The T-X900 was a 1984 intro model priced at about $300. It is the typical low-profile black box but had several interesting and for the time novel features. The controls, from left to right, give a good indication of its features. Power, tuning up and down, freq/dB (digital signal strength in dBµV), antenna A/B, AM tone (bandwidth), FM sensitivity (0, -10 dB, -25 dB ), FM IF bandwidth, mono/mute, QSC/Stereo (forced stereo or computer-selected modes), calibration tone, AM/FM and 10 memory selectors. This model was below the FX-1100 in the JVC lineup. The front end sports 4 gangs in the single-tuned, GaSa FET, double-tuned, mixer setup. There are 3 ceramic filters, one for Wide and two more added in Narrow followed by an LA1235 detector, buffer amp and a uPC1223C MPX chip feeding the outputs through pilot filters. The post-detector buffer made adding a detector out jack for outboard MPX units easy. [In the inside photo, the small blue wire in the center right is part of Ray's mod. -Editor]
"Specs: usable sensitivity 10.3 dBf, 50 dB sensitivity 16.3 dBf mono, 38.1 dBf stereo. THD .0.04% mono, 0.06% stereo; capture ratio 1.0 dB; alternate channel selectivity, Wide 30 dB (only one CF), Narrow 80 dB; IF rejection ratio 100 dB; stereo separation 55 dB @1 kHz; frequency response +0.30 to -1.0 dB 30 to 15 kHz. However, I both calculated and measured a de-emphasis time constant of 59.4 µS and changed the feedback resistors from 33K to 38.9K to get 71.2 µS. (The Euro mode's de-emphasis calculates to 39.6 µS.) The control panel is understated and easy to use and read. This model is rare in the U.S. but it's very likable once the de-emphasis is corrected."
JVC VT-900 (1974, $400, photo)
The VT-900 is a rare 4-gang FM/AM tuner with an analog tuning knob and a large digital frequency readout, somewhat resembling an SAE
Mark VI or VIB. Our contributor John V. tells us that the VT-900 "sonically is for all practical purposes a [Pioneer] TX-9500, maybe a little softer in the midrange. Sensitivity/selectivity is very good - you can 'blur' the readout when fine-tuning a station, and it will stay." The VT-900's specs do indeed claim excellent sensitivity and overload rejection. Its back panel features include a variable muting level control and jacks for an oscilloscope. The VT-900 is rarely seen on eBay and sale prices are erratic: $25 in 3/07, $99 in 7/07 and $211 in 10/08.
Kenwood Tuners can be found on a separate page.
Klein + Hummel
We give this German manufacturer's FM 2002 (photo, with amp, inside, inside 2, German manual, German article) an honorable mention. See the series of posts in our FMtuners group beginning here for great information on Klein + Hummel and its successor,
Kyocera T-910 (1984, $590, photo)
The T-910 is a rare and very unusual digital tuner that is a pretty good performer when working properly, but no one should buy an "as is" one because it's virtually impossible to fix without a service manual (as our panelists Bob and Jim learned). It has 8 memory presets for FM, 8 more for AM, and an output level knob on the back panel. Our contributor Bill T. found that his T-910 outperformed a Nakamichi ST-7, although he thought the T-910 sounded "somewhat thin and closed-in." See how our panelist Jim ranked one T-910 compared to many top tuners on our Shootouts page. The Vintage Knob has a nice page on the T-910 with beautiful photos, as always. The T-910 usually sells for $100-200 on eBay, but two T-910s inexplicably sold for $270 in 6/09 and $335 in 8/09.
Here's a review by our contributor Ryan: "First off, GORGEOUS digital tuner. One of the absolute best-looking that I've ever seen. Every photo I've seen of this thing just does not do it justice at all. Back panel has fixed level and variable outputs, an AM antenna input, and two 75-ohm coaxial threaded FM antenna inputs which are switched by a relay. Initial glance shows 5 gangs and 5 filters. Standard metal fence around the front end. Filters are GDT type for the most part - SFE10.7MXs and a couple that are just 'M', which is rather vague. Narrow mode could thus be made quite selective. Tuning is done in 100 kHz steps by two very handsome round aluminum push buttons. All of the selector function buttons are back-lit by an LED when pressed. Functions: rec cal, MPX filters, DNR, blend, mono, mute off, 25 µS de-emphasis, and multipath. Yes, it does multipath indication, nice. Why in the world there is 25 µS de-emphasis I have no idea. Dolby was dead by this time as far I know. A mystery, I suppose; the 'DNR' would seem to support the built-in Dolby. The inside looks good, with some nice polystyrene caps and 'Audio Use' labeled Elna 'lytics around what I assume to be the MPX and what looks like the audio buffer. I cannot find anything about the multiplex, but it looks like a Harris, so I assume a successor to the fine HA11223W, which was quite good in its own right. It is quite large in physical size, and is labeled HA12031. All in all, a very nice-looking tuner. If you're just some casual guy who doesn't listen to a tuner much, but has a high-end good-looking system stuffed with Krell and the like, and need a digital tuner, and don't want some cheap-looking Kenwood, Sony, or Sansui taking up tuning space, this is THE tuner to own, IMHO, unless you have tons of cash to waste on a new Magnum that you'll only use once in a blue moon." But uh-oh, stop the presses, here's Ryan again with a revised view: "The Kyocera T-910 is a piece of complete and total garbage. Every single unit I have heard of has the same problem, and it's a design issue. There is a ghastly low-level high-pitched whine that you'd have to be half deaf not to hear, although it can be more or less pronounced at any given time."
Lafayette LT-425T (inside, schematic)
The LT-425T had 4 FM gangs and 3 AM gangs and might be worth seeking out on eBay. It should be possible to pick one up for $10-30.
Lafayette LT-D10 (1974)
Here's our panelist Ray's review: "The LT-D10's exterior looks 'Pioneerish' with its blue lights and dial scale. The walnut enclosure and screen also look very similar to what was on my old SX-770 (1971) receiver. Inside, though, it doesn't look so Pioneerish. The components, layout and overall build seem more dated than my even older TX-6200. According to some web info, the LT-D10 was available from 1974-77 from Lafayette but methinks its technology is older than that. It's smaller than the norm for a standard component and its black face seems out of step for the times also. Also, the construction seems to be more of what would be expected from a lesser tech source... not bad, just less automated. The front controls, left to right, are pushbuttons for Dolby noise reduction, FM/AM, stereo/mono, MPX filter, FM mute, dimmer, power and a tuning knob. On the back are a 25/75 µS switch that is only effective when Dolby NR is selected and jacks for fixed and variable out (with control) and a detector out. Methinks the person reporting CD-like sound with Dolby NR selected also has the de-emph switch in the 25 µS position.
"The very small tuning cap is 4-gang FM and 3-gang AM. The RF amp is a dual gate FET. The IF string starts with a metal can Murata ceramic filter followed by two IF transformers. There's an early Texas Instruments SN76115N MPX chip and all else is discrete from there. The sensitivity from the work bench was a nice surprise, the dial scale is not precise and is somewhat off and the sound, though that system, seemed to be both accurate and robust! Much better than the stock TX-6200 was. Subjectively, after one of RFM's amateur tuneups, its sensitivity is good, selectivity 'OK' and sound... rather enchanting. RFM really enjoys using this tuner in his rural environs but suspects dwellers in RF-rich cities may be disappointed. The bass response is very strong, heard and measured. The de-emphasis is passive and 82 µS which give a rather mellow sound. The pilot filtering is very effective but bites a bit into the 15 kHz audio response. The wood cheek plates and charcoal front panel are different from the usual and quite nice." The LT-D10 is rare but should still sell for $25-50, max, on eBay.
Leak - See the Tube Tuners page for information on Leak's Trough Line series of tube tuners.
Linn Kremlin (1994-2000, $4,400/orig
$3,700, open, closed, inside, top board, main board)
Our panelist Jim did a Shootout with this rare and very pricey British tuner and provided the above photos of its insides. The first photo shows a full inside view, the second is a closeup of the top board which holds the audio section, and the third shows the main board with the top board removed from the tuner section. Jim didn't see any common ceramic filters and didn't pry open the three cans. Our contributor Nick says, "The Kremlin seems to be a typical British tuner in that they sound super with a strong signal but have poor sensitivity. Why this seems to be a common characteristic of Brit tuners I don't know. If they upped the sensitivity, it would make more stations listenable." The Kremlin has 80 station presets, but it was not sold with a remote control so you'd need a remote from a Linn preamp for direct entry of the tuning frequency or preset number using a numeric keypad. The LED display shows tuning mode, signal strength and mono/stereo. Please post in our FMtuners group if you have any personal experience with the Kremlin.
Linn Kudos (1995-1998, $1,750/orig $1,195)
We have no personal experience with this high-priced tuner. Please post in our FMtuners group if you've used one. Our contributor Pete G. says, "I had this tuner several years ago, and the sound of it just left me cold. Nothing was really bad-sounding about it; it just sounded boring. The audio had a constricted, non-dynamic characteristic. The display that indicated the frequency and signal strength would black out after about 30 seconds, which would seem to indicate that the designer didn't know how to get rid of emissions that would come from the microprocessor. Yamaha did the same thing with the digital display on the T-2.
The marketing folks will tell you all day that this will improve the ultimate S/N ratio, but if everything is shielded properly this shouldn't be an issue. OK, I'll give the Kudos one bonus point: The signal-strength meter indicates RF level in dB relative to 1 microvolt. They do use aluminum construction. It's just too bad that they didn't get the sound right.
"If you can pick up a Kudos for under $300, it isn't a bad deal if you like to do MW/LW DXing. This is the only tuner that I have seen so far that actually uses a dual-conversion scheme in the LW/MW ranges. The first IF is 10.7 MHz, while the second IF is 455 kHz. This is fairly evident when you see the 10.245 MHz crystal next to the TDA-1572 second IF subsystem. The only solid-state synthesized tuner I have that works better on the MW band is the Hafler SE-130. The Hafler unit uses a Hughes-Delco radio board. This thing is really hot. Hafler talks about the doubly-balanced mixer that is used, but since I don't have a schematic, I don't know exactly what topology they are using. It could be a Gilbert cell mixer." The Kudos used to sell for $300-500 or more on eBay, but around $200 is now the norm.
Linn Pekin (2001, Pekin inside, Pekin specs)
The British magazine Hi-Fi World had this to say about the Pekin: "Good when it comes to facilities and features. The Pekin suffers from insensitivity [a common problem with British tuners - Editor] and a slightly thin sound, although vocals are clear and detailed." Our contributor Ed K. saw the inside photo and specs and observed, "Nice big empty box. I notice that the Linn spec sheet carefully avoids mentioning the RF parameters that most people here would be interested to know. 'Fully screened low-noise circuitry to avoid interference'? I don't see much screening (and it has a switched mode PSU?). 'High overload margin and high sensitivity for clean capture of faint signals in crowded airwaves'? So what are the figures?"
Our contributor Bart said, "I don't think a service manual exists. It has a nasty 'hi-blend' (less or no stereo) on signals less than '50' - the meter's max. That's a 'feature' :-). You can bypass that behaviour with a 20 dB amplifier. There is really nothing inside you can adjust, except for the front end maybe. It contains the 10.7 MHz IF circuit and filters, nothing special really. It's all in the firmware. The tuner uses a H8 legacy single chip 'computer' to control everything. The sound with the hi-blend defeated is very good, but the sensitivity is low. It's a typical tuner for cable radio, when all signals are the same maximum strength. This tuner is overpriced, IMHO." And our contributor AlanM added, "Yes! I returned two second-hand Pekins because I thought that hi-blend 'feature' was a fault. Even with a 6 element well-aimed roof aerial with line-of-site to the transmitter around 20 miles away and most stations showing the maximum '50', the display showing 'stereo', and no audible hiss, I only once heard proper stereo from these units - BBC Radio 3 during particularly favourable reception conditions one balmy summer's day. All other output sounded so close to mono that it more or less was. You had to listen to something obvious like the Beatles with their hard panned stereo tracks before you could just about detect signs of stereo. I wrote to Linn and contacted hifi shops about the issue; I just could not believe this was deliberate, but all avenues drew a blank, with whoever designed the circuit in the '80s or '90s is probably dead by now or at least impossible to trace. Linn offered to test the tuner, but at a price. I thought I was the only one to notice this bizarre implementation of a feature which logically should only kick in for very weak signals and be completely defeatable. Was a shame because the sound, even as it was, hinted at being a good solid performer with well-defined bass and smooth highs, but alas, I would've had to move next door to the local transmitter masts to ever hear this tuner at its best."
Our contributor Cord adds, "I like the Pekin because it is for me till now the best tuner - for my needs. I live 30 km from Hamburg (Germany) and it is important to have a sensitive tuner - noisefree and a good sound is also important for me. In this special geographic situation the Linn beats in the last years the Carver TX-10 and TX-12, Arcam Alpha 7, Marantz ST-17, Kenwood KT-5020, Creek CAS 3140, McIntosh MR 77 . . ." [and some other lesser tuners - Editor]. The Pekin used to sell for $300-500 or more on eBay, but around $200 is now the norm.
Luxman Tuners can be found on a separate page.
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