Popular Posts

Sunday, February 21, 2016

Spring cleaning and the Sony STR-GX90ES Stereo receiver

Yesterday it was over 50 degrees Fahrenheit here in New York, so windows got opened and some much needed spring cleaning got started. This of course meant that a change in set up happened in the listening room.  The Yamaha A-S2000 integrated and CD-S2000 disc player had been running the show for a long time (over a year) and I was ready for something different.  I had ordered a pair of casters from Audio Advisor for the Salamander rack that holds the gear that is out of current rotation, so everything had to come off to install them anyway.  Here is the mess when it was in progress:

My only real complaint with the Yamaha A-S2000 integrated amplifier is that in my room it is impossible to determine where the volume indicator is, especially in low light.  This may not seem like a big deal, but when you are trying to make comparisons, having the volume consistent is useful.  I decided to set up a Sony STR-GX90ES stereo receiver I got for a song on EBay some years back as the heart of the system for now.  A green indicator is built into the Sony's volume knob, so that would be one matter resolved.  Here is what I would up with after some futzing around:

It's an all ES system, with the Sony SCD-X5400ES as the disc player and my TC-K700ES tape deck in the "loop."  (Heh.)  For the earlier part of the afternoon, I had the Dynaudio Excite 14s making nice noises.  

I was once the proud owner of a Sony STR-GX9ES stereo receiver that despite the best efforts of the talented folks at In House Repair (I hope Wayne is still out there) gave up the ghost.  You can read about that here. I loved the way the GX9 and its more elite sibling the GX10 looked.  The GX90 is a bit more streamlined, unfortunately, and all of the nifty buttons are hidden behind a drop down panel.   Not everyone appreciates it, but I grew up with the clutter of buttons on black boxes from the eighties, and I miss them.

I don't have the shipping container for this machine, and I am currently hunting for an original remote (I have another that works well, but I'd like to get the full set, of course).  My manual (which it shares with the GX80ES although they do not have the same feature set and performance, GX80ES omitted here for brevity, let me know if you need the information) provides the following info:

Sony STR-GX90ES FM-AM Stereo Receiver  

Power output and total harmonic distortion:

With 8 ohm load, both channels driven, from 20-20,000 Hz, rated 120 watts per channel minimum RMS power, with no more than 0.008% total harmonic distortion from 250 milliwatts to rated output.

With 4 ohm load, both channels driven, from 20-20,000 Hz, rated 120 watts per channel minimum RMS power, with no more than 0.015% total harmonic distortion from 250 milliwatts to rated output.

Amplifier Section
Dynamic power output

160 watts + 160 watts (8 ohms at 1kHz IHF)
220 watts + 220 watts (4 ohms at 1kHz IHF)
350 watts + 350 watts (2 ohms at 1kHz IHF)

Harmonic distortion less than 0.008% at rated output

Frequency response

PHONO: RIAA equalization curve +/- 0.3dB
CD, DAT, TAPE, VIDEO 1,2,3 (AUDIO), ADAPTOR: 20-20kHz  +/- 0.3dB

Damping factor 60 (8 ohms, 1 kHz)

Sensitivity: 2.5mV
Impedance: 50 kilohms
S/N (weighting network, input level): 90dB, 80dB (A, 5mV)

Sensitivity: 0.17mV
Impedance: 100 ohms
S/N (weighting network, input level): 73dB, 84dB (A, 5mV)

Sensitivity: 150mV
Impedance: 50 kilohms
S/N (weighting network, input level): 98dB, 85dB (A, 5mV)

Sensitivity: 1.1 V
Impedance: 50 kilohms
S/N (weighting network, input level): 120 dB (A, 5mV)

The STR-GX90 has a set of three tone controls which allow for fine-tuning with the use of selectable turnover levels.  The manual states:

Response +/- 10dB at 100 Hz Turnover frequency: 400 Hz
Response +/- 7.5dB at 100 Hz Turnover frequency: 200 Hz

Response +/- 6dB at 100 Hz Turnover frequency: -----------

Response +/- 10dB at 10 kHz Turnover frequency: 3 kHz
Response +/-   6dB at 10 kHz Turnover frequency: 6 kHz

Overall I find the tone controls to be pretty subtle unless they are maxed out.  There is an impedance selector switch on the rear panel that I must check as I switch speakers. 


w 18 5/8 x h 6 3/8 x d 17 1/4 inches

Weight: 32 lbs (which is a little over two pounds heavier than the GX80ES, interestingly)

Some other details from the manual:

The STR-GX90ES is equipped with a copper-plate rear panel for reducing distortion in high frequencies.

Optical Legato Linear A system allows the receiver to operate automatically as a class A amplifier when the level is low and as a class B amplifier when the level is high without disturbing the signal.  This minimizes total harmonic distortion at every sound stage.  These receivers have a spontaneous twin drive power circuit.  Condensers having large capacity are used independently for the voltage amplification drive stage of the class A and power output stage of class B.  Thus, a stable output and high quality sound are obtained, resulting in exclusion from power interferences.  The class A stage realizes a stable operation free from interference of the power stage even when an instantaneous or strong output is received.  

And they silk-screened that in Sony Gold right on the front:

Here is a so-so picture of the top.  It's very nice, but does not compare with the Yamaha A-S2000 in terms of interior eye candy:

I don't have the exact info on the MSRP of the GX90ES yet, but the previous Sony ES stereo receiver flagship, the STR GX10ES retailed for $1,200 in 1990 (which is roughly $2,175 today- that's an 80 percent inflation rate, approximately). 

How did an afternoon of listening go?  Great.  Keep in mind that I have not had the GX90 serviced, which it definitely deserves.  I do not know how close to operating spec it is functioning (I need a crash course to make this blog better . . .  any volunteers?)  but it certainly sounded different to my ear.  I am very used to a super clean and effortless sound from the Yamaha.  The Sony sounds somehow . . .  rounder, if that makes sense.  But let's not forget that I ALSO switched out disc players, going from the CD-S2000 SACD player to the SCD-XA5400 ES.  Despite owning them for some time, I still haven't done a comparison between those two.  Furthermore, the GX90ES does not accept balanced inputs, so I went from Kimber XLR to Audioquest  Golden Gates.  To some, these changes are meaningless.  To others,  well, they are a big deal.  At any rate, this is the intended set up for a while.  I think the next post will be about the TC-K700ES tape deck and its adventure in Alamogordo, New Mexico.  Stay tuned. 

Monday, February 8, 2016

The NAD 3125 integrated amplifier, a Sony CDP-X55ES CD player and the Buffalo News

The A/D/S/ R1 stuff was so much fun to write about that it prompted me to get out my NAD 3125, as it is my all-time favorite amp (so far) and it was the first piece of 'high end" gear I ever owned.  I guess it's high end, I'm not sure how one goes about defining that.  The pictured example is my second.  When I bought my first one in college in 1987 or so (have to check on that date) no one in the dorm had ever heard of NAD, and there were some big Kenwood and Pioneer fans on my floor, so people had been to Crazy Eddie's and thought they knew a thing or two about stereo. In this case high-end certainly can't be based on price, as the 3125 is a killer amp that sold for very little money, even when new.  For a short time over the weekend I had it paired up with a Sony CDP-X55ES thusly:

I still had the A/D/S/ L470 out, so I was running those.  Short review: if you find one, buy it.  I would certainly think nothing of paying $200 USD for another one if it were in nice shape, especially if it had manual and box.  Here is Junior grooving to a Jean Sibelius symphony (or was it a Tone poem?):

My sophomore year as an undergraduate at Niagara University I had a very nice Technics/Cerwin Vega system that fared well in the dorm stereo wars, but I always knew it was sort of goofy sounding.  I even dragged the system down to the Rathskeller to DJ some parties, and it had a lot of cool lights and could play loud.  I don't know how many drunk women asked for me to play Brown Eyed Girl on it.  But it sucked for Chopin.  By this time I had discovered The Absolute Sound, and I think Stereophile as well, so I was itching to get something better.  I was aware of NAD and A/D/S/ for example from my Uncle's system, and I cobbled together something like $800 to upgrade (a pretty good amount for the mid eighties and my beer proclivities).  Not knowing how blessed we were, back then most cities had two or three hifi shops within reasonable driving distance, and my good friend JP gave me a lift out to the Speaker Shop to get an idea for what I could afford.  The Speaker Shop was (and still is thank goodness) located near the downtown State University of New York at Buffalo campus.  Here is their homepage:


Please visit.  They were very nice to poor college students.  They let JP and I listen to Audio Research and Magnepans.  I was too poor though, to do what I wanted to do: separates.  I was starting from the ground up after selling the Technics set up, and for a little while I thought about dumping the whole $800 on a pair of headphones and a disc player, which probably would have provided greater fidelity.  But no,  I was still somewhat social then (Not now.  Everyone can go straight to blazes now.  Do not pass "Go,"  do not collect $200. I really cannot stand people), and figured I would want to play tunes for someone else (girls maybe, probably, who knows, I don't even) so headphones wouldn't cut it. I did wind up buying an $80 pair of Nakamichis anyway based on JP's recommendation, and they were great.  I wonder where they are.

To make the budget work, I would need to go with an integrated amplifier (no McIntosh separates for me) and I would have to buy at least some of the gear used.  Certainly the cables.  Recall dear reader that this was 1987 or 1988 or both, and the interwebs only really existed then for academics to use message boards on usenet, no pretty graphics of Kate Upton in ZERO FREAKING GRAVITY, no Angry Birds.  No EBay, no Craig's List (what did the Nigerian Scammers do for fun back then?  Oh, right, stuff like this: http://www.ncbi.nlm.nih.gov/pubmed/2617590). To find used stereo gear I had to use the classifieds in the back of the -gasp- Buffalo News.  I recall getting newsprint on my fingers.  Can you imagine what treasures people were selling used in 1987?  I wish I had kept those want ads.  I later also used the Buffalo News want ads to buy a Dual CS-5000 from a guy who was an industrial designer working for McCormack, but that is another story (a very cool one).  I wound up contacting a fellow selling an NAD 3125 integrated amplifier for the princely sum of $125.  JP being the trooper that he was and is, not to mention with what must have been a morbid sense of curiosity, accompanied me to some stranger's home somewhere in Western New York one evening to see the amp.  I barely recall the event now, but I do know that the amp was not hooked up.  It was not plugged in.  It had no documentation.  It did come with a .5 meter pair of Audioquest cables.  So of course I promptly bought it for the fully advertised $125, and as we walked back to the truck, JP commented that I "had big brass ones," which was a very polite way of saying that I was an idiot.  Well played, no arguments there.  Luckily, that amp worked.  Well.  

Later that week (if I recall correctly) we returned to The Speaker Shop where I dropped the remainder on a Sony CDP-208ES (yes, that's where THAT obsession started) and a pair of oak-finish Klipsch KG2 speakers, which just happened to be the perfect match for a 25 watt NAD amplifier.  That's right, 25 wpc.  Here are the details, per the manual:

Date of Manufacture from January 1985


Phono input
input impedence (R and C)                                     47 kilo ohms/ 100 picofarads
input sensitivity, 1kHz                                            2.5 mV  ref. 25W
Signal/Noise ratio (A-weighted with cartridge connceted)  75dB ref. 5 mV
RIAA response accuracy (20Hz to 20kHz)             +/- 3dB

Line level inputs
Input sensitivity (ref 25w)                                       150mV
Signal/Noise ratio (A -weighted ref 1W)                  86dB
Frequency response (20Hz- 20kHz)                         +/-0.5dB
Infrasonic filter                                                         -3dB at 15Hz, 12dB/octave

Tone controls
Treble                                                                        +/- 7dB at 10kHz
Bass                                                                           +/- 10dB at 50Hz

Continuous output power into 8ohms*                     25W (14dBW)
*minimum power per channel, 20Hz to 20kHz, both channels driven with no more than rated distortion
Rated distortion                                                         0.03%
Clipping power (maximum continuous power per channel) >35W
IHF Dynamic headroom at 8 ohms                                       >3dB
IHF dynamic power (maximum short term power per channel)  8ohms  50W
                                                                                                      4ohms  55W
                                                                                                      2ohms  75W
Damping factor (ref 8ohms, 50Hz)                             >50

Dimensions (W x H x D)                                            420 x 83 x 288mm
Weight                                                                         4.7 kg 

How would a puny 25 watt amp survive dorm life?  Would the girls in the next dorm over even hear  the opening lyrics of Black Dog blaring from the speakers hanging out of the windows at 8AM on Sunday mornings?  Why yes, yes they would, if those speakers dangling dangerously from the window sill by Monster Cable XP have a 90dB sensitivity rating and that little amplifier has 3dB of dynamic headroom. 

As you can see from the pictures above, the NAD 3125 is small.  It's even smaller than a Rotel DVD player:

In fact, it was dwarfed by every receiver in that building, but it easily blew them away.  It conquered not because it was loud, which when paired with the Klipsch's it was, but because it could play loudly and cleanly, with musicality.  Its' tone controls stayed flat, its' loudness button never got used.  it was accurate and just played music, and what noise it did add did not detract from the listening experience.  I used to love pointing out that the CD player was NOT the amp, and all the noise was coming from the little guy on top of the disc player.  Some of the more savvy accused me of using it as a preamplifier and hiding the amp elsewhere.  Not so.  The NAD 3125 is just super cool in a sleeper kinda way.  Plus it had really, really excellent external heat sinks (a sure sign of being high end, right?  Careful though, they are sharp):

As you can see from this picture, the current example I have has a coveted "Ontario Hydro Electrical" sticker, in the official orange (!).  This example I bought a few years ago complete with box, packing and manual (anyone need a PDF?).  The original one was unfortunately replaced by another, older and bigger NAD after I graduated, a 3150 I think.  I have owned a few other NADs since (not as many as one would think, given my issues), and I have a 3130 stereo receiver in my office whose only source is a Sony TC-K606ES tape deck.  I just had to have another 3125, though, and the one I have now is a forever piece.  I may request that it be buried with me.  They can use it to blast Bullet the Blue Sky during the wake.  Now THAT is a late eighties, early nineties Catholic University Student reference for you.  

This story can go in a bunch of directions from here, such as how the NAD paired with the X55ES, what happened to the KG2s (JP got them and recently sold them- shoulda called me first . . . ) or how the 3125 compares with more modern NAD amplifiers.  If anyone has any preferences, let me know.  For now I will warp this up by repeating- you probably want to get one of these, before they disappear forever.  It is a five-star piece of kit, in my not so humble opinion.



Wednesday, February 3, 2016

Update on adsspeakerservice.com A/D/S/ R1 stereo receiver and L470 speakers

Howdy- quick update.  Mr. Richard So of Richard So Electronics at adsspeakerservice.com replied to my request for information and confirmed that he is indeed still repairing A/D/S/ speakers.  The site again is:


Mr. So indicates that he is the only one using original A/D/S/ parts to repair these rare speakers.  If you are an A/D/S/ fan, I highly recommend that you read the "about us" on his website, as it provides a brief history of this iconic audio company.  I do not currently have a need for speaker repair as my L470s are in great condition, but I will definitely keep him in mind when I find that pair of L1590s that are in need of some help!

Monday, February 1, 2016

Part II: a/d/s/ R1 receiver and L470 speakers - The NY Times Approves of Braun Innovation

Well, back at it.  There is not as much information on a/d/s/ gear to be found, so I am trying to pull a bunch of it together in one place.  I currently own an a/d/s/ R1 stereo receiver in pretty decent shape, and a pair of L470 series 1 speakers that are excellent.  I also have the opportunity to listen to a pair of L1590s from time to time (driven by Emotiva now), and suffice to say I am a very big fan.  In our last entry, I included information from the 1986 Stereo Review equipment guide, and went on a little bit about the R4, which is the R1s superior successor.  If I come across a mint R4 I will probably take the plunge, but for now, let's focus on what we have in house, shall we?  I found a few valuable links to info about the R1, starting with an article in the New York Times (!) written by Hans Fantel in April of 1983.  The entire article is here: 


I do not currently read the Times, as I find the Arts section generally to be fit only for the cage linings of non-discerning parakeets.  I do not believe that the Times in its current iteration provides any news content.  That being said, there was a time when it was not so, and this article is from that era and well worth looking at.  Deiter Ram is mentioned, and Fantel confirms that the "Linear" button disengages loudness compensation when depressed and attributes the feature to the needs of those who listen at low or moderate volumes.  Such is not the way of this humble blog author, so I will typically press the "Linear" button.  I also found this site:


which is maintained by Richard So, who joined a/d/s/ (A/D/S/ on his site, so I may have some corrections to make) in 1987 and provides speaker repair services.  Other than that I know very little about the site, so I hope to change that.  I will reach out to Mr. So to make sure that the link is valid and the services are still available.  If so, that is very good news.  More to come on that.  Next, I discovered this: 


Which is a very neat site with a cool review of the R1 along with the L400 loudspeaker.  The site is run by a gentleman named Ken Rockwell and frankly, I think his review of the NAD 7100 is absolutely killer.  Definitely check it out!

You can also find info regarding the R1 at The Vintage Knob.  If you haven't visited TVK by now, you are wasting your time here.  It is the Mecca of sites for vintage gear, especially 1980s Japanese stuff.  I love it.

What better way to test the R1 than with a set of a/d/s/ speakers?  A while ago I picked up a pair of L470 2 ways on EBay that were in excellent condition.  They were entry level in the non "miniature" line (L400 etc), and the info I have (again from the Stereo Review 1986 equipment guide) is:

2-way acoustic-suspension speaker with self-resetting solid state tweeter protectors.  Features 7" stifflite woofer and 1" soft-dome tweeter.  Walnut vinyl or black finish.  FR 50-20,000 Hz +/- 3dB; crossover at 2kHz; sens 88dB SPL/W/m; nominal impedance 8 ohms; 16" H x 10" W x 9" D.  $320.00 a pair (that would be about $692.00 in today's dollars.  The R1 would go for approximately $1,079).

I am not a huge fan of the vinyl finish, but I love the classic a/d/s/ black metal perforated grill.  This set has no dents and no scuffs. 

So, in the short hour or so I had the things hooked up, what happened?  First off, I had to break out a set of pin connectors from Monoprice (need connectors?  Do yourself a favor: http://www.monoprice.com/)  because the R1 and the L470s only accept those or bare wire.

I dug up a pair of old IXOS cable I got from Accesories 4 Less (Have an urge to buy an inexepensive Onkyo something or other?  Go here:  http://www.accessories4less.com/  I see they have the Yamaha A-S3000 Integrated for a mere $3,999.  I shall order one now) and clamped on the pin connectors and promptly only got one channel worth of sound.  It would have helped had I read the diagram on the back of the R1 that showed that the speaker inputs are stacked (see yesterday's post for diagram).  A few minutes of swearing later, we were off and running.  Seriously, I thought at first that the spring clips in the connectors had worn out or could not handle the weight of the pin connectors, as they are quite heavy duty.  But it was just the glitch of hooking up Left A and Left B.  Corrected that, and all was well.  

The only disc player I had that wasn't already on duty elsewhere (no, really) was a Rotel RDV-1040 DVD player that I bought at a thrift a few summers ago for I think seven dollars or so.  That was a winner.  It is not the most solidly built machine, but it sounds all of seven dollars great and then some.  Plays both PAL and NTSC so it has that going for it too.  

A big down side is that as you can see, the L470s are pretty big for bookshelves.  They dwarf  the Dynaudio Excite 14s, for example, so I have no appropriate stands for them.  I have seen some proprietary stands that seem quite low, 12 to 16 inches I would guess, and I will need something like that.  I refuse to buy the crap stands that are floating around out there, and the good ones are eye-wateringly expensive, so I will be making my own at some point. This summer, I think, if I can figure out what I want them made out of.

As a result, my brief listen was done with speakers on the floor, me reclining on a couch pillow roughly midway and equidistant from the speakers.  Very old-school college bohemian style, I guess.  I put on some Joe Jackson, Christopher Cross, some Bowie and some Tears for Fears, nothing critical, just Sunday night casual.  Darned if they didn't image very well on the floor even- vocals were nicely separated and the sound stage was easily wider than the two speakers.  The bass suffered with the floor placement.  There is a crawlspace below the listening room and the reinforcement made the lows too powerful and out of sync with everything else, which is not the fault of the speakers.  The R1 is not remote controlled, so I had to play with the tone controls and volume the old-fashioned way.  Ultimately I left everything flat and the volume somewhere near the ten o' clock position which was fine for the fairly mellow tunes I was playing.  Overall, I was very, very pleased.  The sound definitely reflected the age of the speakers.  They were clean but not analytical, they were accurate but not "smooth" in a phony way.  They probably do Blue Oyster Cult well, and I am sure they would do Gustav Holst justice.  I will also bet that things will improve astronomically with the right stands.  I see a shoot out with the B&W DM60i in the future.

In my opinion, a/d/s/ made some of the very best stuff around in their day, and their speakers are still my second favorite.  They established a design and sound standard that is hard to find in stereo now, at least for gear that is under high four and five figures.  When they were new I certainly could not afford them, but now it is well worth hunting for examples in good condition.  You will note that I did not mention that I cleaned the R1 after getting it.  That is because I did not.  It just worked.  That is not to say that I will not open it up and give it a good going through, I will.  Thirty years on though, it's a testament to initial quality that it still works so well.  If you can find one, give it a shot as it will likely be different from what you have experienced.  And a/d/s/ speakers are a no-brainer.  it is hard to find a pair without the soft domes damaged however, so I will look into the repair site mentioned above.  And if I come across that mint condition R4 . . .