QR-6500 for $30...fair?

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tejanoboy

Active Member
Joined
Jun 17, 2009
Messages
88
Location
warren michigan
Just picked up a Sansui QR-6500 at a flea market for $30. I know it has just a basic QS decoder, probably no logic, but it seemed like it would make a neat restoration project. Nice looking "classic 70's monster", but did I pay too much? This is my first Sansui, just maybe a stepping stone to a QRX-?
Thanks,
TB
 
I have no idea what a fair price for the Sansui would be. But, the most you could have possibly overpaid is $30, a couple of bucks more than one of the King Crimson DVD-As. How could anyone pass? Enjoy the restoration!
 
If nothing is burned out (except lights), you did very well. It will probably need the pots and switches cleaned, maybe some lights replaced, and some wiping off on the exterior. On something that old, you may need to replace some capacitors (best to do them all at the same time), they don't cost much, but the labor in a shop can.
 
I have one, it really has a great sound. Did some minor restoring, mainly cleaning and replacing some bulbs and a am/fm tune up. Also made sure the amplifier bias was set properly. Other than a problem with FM cutting in and out (probably due to the integrated chip carefully manufactured from a material know as "non-obtainium"), it really has a great sound. No, the quad function is not as good as the QRX ..01's, but I think you will not be disappointed.

btw, e-bay prices on a good, clean unit are now a 100 or so, plus 35-50 freight.
 
Thanks, all! Geotex, you mention amplifier bias, is that what those trim pots near the output stages are for? I have an ancient distortion analyzer, just hook it up and set for minimum distortion at high power, right? (It's been a while!)
First order of biz is a BIG cleaning, there is enough dust in here to do a vacuum cleaner commercial!
TB
 
Not quite. Basically, startng with the left channel (FL, FR, RL, RR) you set volume to zero level, remove the fuse from each channel one at a time, putting an ammeter on 100 ma scale across the empty fuse holder and adjust VR802 for 25-30 ma. (each channel amplifier should have the same numbers for all components) Then, when balanced, you could use your distortion analyzer. Or, if you have a scope, input a 1000 Hz. audio signal, put 8 or 16 ohm resisters (40 watt or larger) across the outputs and using the scope, raise the volume level to clipping, then set VR801 for equal clipping on each side of the sine wave.

Stupid me, forgot the caveats.... Be sure to turn off the unit before inserting or removing fuses!!!
 
Ah, thank you! Guess I'm still livin' in the tube era sometimes. Not to worry, I would have turned off when pulling fuses, but a valid warning all the same.
I'll get a repair manual one way or another, kill two birds with one stone...(a) identify the pots, and (b) copy the phase shifters, so I can start ENcoding QS or DPL-II.
Thanks much,
TB
 
Granted, the 6500 doesn't have the uber-matrix, but it does a right fine job with what it's got. The QR series receivers strongest feature for me was always the flexibility. You can run two rooms of stereo as well as quad in the main room by just flipping the switches. If power is an issue (and 40 watts per channel is great, but 600 is better ;-} ), you can hook an outboard amp to the pre-out/main loop, get kick ass power to infinity or whatever your budget allows, and run three rooms stereo. For whatever reason, all the later Sansui quad units dropped the separate speaker selectors for front AND rear, and got rid of the pre-out/amp in loop. I miss those features. And you've already mentioned (or somebody did anyways) they are some classy looking beasts.

If you haven't got a lot of old quad source to play with, the QR is an excellent front end for an SACD player. I've got an old Carver cube with one good channel that I use for the center channel and run a big amp for the front channels, so don't need a sub. You end up with pure five channel, and still have the quad synth capability to open up your stereo source material.

I ran a 4500 for years (basically the same machine with less power output), "upgraded" to a QRX-9001 (which is now on the bench with typical QRX issues) and am currently running a QRX-6001 as the primary receiver. Admittedly, the fancy matrix does do some amazing things, but overall, compared to the QR, it sounds harsh to me. Somebody's sure to pipe in about me having a tin ear and all, and yes, there are maintenance issues with my QRX equipment, and yes, a lot of it is what you're used to, but there it is. Probably a lot like the old transistor vs tube argument, and don' get me started on the "Boston Sound" ... :rolleyes:

The QRs aren't the maintenance hogs that the QRXs are getting to be. If you're not into all the bench work an unworked QRX would probably require to make it shine, you may have just made the best choice, especially at the price. Clean the controls, replace the lights if needed, plug it in, enjoy. You <may> benefit from a minor recap (just the biguns in the power path) as the old caps do lose oomph over time and can get a bit muddy on the deep bass.

Oh - the fuse lights in the dials and meters are getting kinda hard to find. Here's a link if you need them.

http://www.mcmelectronics.com/product/25-080

You'll need 8 and should plan to replace them all if you replace any. Probably best to order a couple extras for breakage as they can be a bit clumsy to get to. I let em burn overnite after replacing them - if they're all still working in the morning, chances are good they'll last for years.
 
Thanks! I assume the decoder is a straightforward QS, so I am not going to expect a lot of separation, but with the diagonal zero-crosstalk of QS, I am sure it will have a decent sound image for what I paid. (If separation becomes my big thing, I have a Pro Logic II rig that gives plenty of that)
Hopefully, I'll get to fire it up this week-end and see if it works.
BTW, I'm not sure how to begin a thread, so I'll ask here, and hope I am forgiven...
Were there ever any movies that actually had the "QS" logo in the film credits at the end? I could swear I once saw that, but can't recall what film it was.
Thanks for all the help, and encouragement!
TB
 
http://members.cox.net/surround/quaddisc/quadQVM.htm

Not sure if an old copy of a VHS what was copied from Betamax what was copied from the old Super 8 will still have the original quad encoding, but as a rule, because of the way QS was encoded, the receiver <should> be able to pull it out.

Separation is definitely better with the later generation vario-matrix found in the QRX and QSD series, but you can still get some pretty neet stuff out of what you got. You can help things out a lot by being real careful with speaker phasing and placement, and carefully balancing the system. You'll find that generally, quad has a very specific "sweet spot".

Truth be told, I'm not much into the wOw effect of instruments flying around your head anyways. Not to say it ain't fun pulling out Dark Side of the Moon or Tubular Bells and letting them rip. More into the subtle ambience a quad setup makes. I use both A&B rears - big boxes back at the corners and a set of Bose satellites mounted high either side of the big chair - adds a lot of depth. Those and the BIG bottom of the McIntosh amp on the front channels can make the room hover. Wanna have some real fun, hook an extra ceiling speaker between the left/right front positive speaker leads to create a ghost channel.

If you check the equipment list in my sig, you'll find I'm not adverse to experimenting around with signal processors either ... all of which tend to minimize any lack of separation the older QS stuff has. Think expanded enhanced quadrasonic holography, oh my.

Oh. Don't remember if it's been mentioned yet or not, but the QS receivers FM tends to blow chunks compared to the QRX. Then again, a decent HDFM outboard box will run rings around any analog tuner. Hard to beat off the air CD quality digital reception.
 
As long as the phase and amplitude relationships go unaltered, the audio can go through a LOT of copying and still decode correctly. I have a cassette that was copied from a reel, that was copied from vinyl, and it decodes just fine, albeit with a bit of hiss.
As for FM, most of the stations (here in Southeast Michigan, anyway) are DPL-II encoded now on their analog signal, and the one I'm usually on is GREAT! I'm not sure if they have gotten ahold of 4-track recordings, or are using that new gizmo makes 5.1 out of stereo, then feeding the 5.1 into a DPL-II encoder...whatever they are doing, it is a very good quad sound, and even the commercials and jingles are a lot easier to take.
I'm with you, I go for realism, especially with nature recordings, but the occasional drum-around-the-room with delayed echo on an FM jingle IS kinda cool.
Check out youtube, search "WTUE Jingle", they have a quadraphonic jingle from 72 or so. I think that station was SQ, I get SOME quad effect with DPL-II, and a little with hafler, (I have no SQ decoder) but it's neat that ANY encoding survived the low-bit rate trip through youtube :>)
Signal processors? Oh boy, gotta confess, I am still an old AM border-blaster lover at heart (long live XERF!), and every so often, will run the stuff through a multi-band compressor/limiter/clipper, just to make it LOUD and PROUD...now I have no doubt really raised the eyebrows of some audiophiles, sorry guys!
Hey it's ALL good, long as it's FUN, right?
TB
 
Ah ... flashback!

Get yer boogaloos out, baby. The Wolfman is EVERYWHERE!!
aWOOOOOOOOOoooooooooo!!

I remember (sort of) listening to RFT (Radio Free Tihuana) over in sunny? SE Asia. The radio guys would drag him kicking an screaming out of the ether and scare the hell out of the locals ... <G>
 
Finally fired up the QR-6500, and it works quite well! Haven't hooked speakers up yet, just tried headphones on both front and back. A few noisy pots and switches, no big problem, but one bulb is burnt out. It is on the lower end of the radio dial, and it LOOKS like a huge mess getting at it. Is there a hidden passageway, or do I really have to pull a circuit board or two out?
I will, but hope not to get crazy doing it. Man, this thing is a good receiver, quad or no quad! Have it in the basement, NO antenna hooked up, and got a dozen FM stations in stereo. AM, got several out of state, and from Michigan, for a moment or two, XERF in Mexico! Guess I have the habit of thinking Sansui just for quad, I had forgotten they really were a great receiver builder, too. Yeah, I got a warm feeling seeing/hearing the old girl come to life...Ah, the 70's...
TB
 
one bulb is burnt out. It is on the lower end of the radio dial, and it LOOKS like a huge mess getting at it. Is there a hidden passageway, or do I really have to pull a circuit board or two out?

Been a while since I've had one, but I <believe> you should be able to replace the lights without too much disassembly. Take the top off and you'll notice there's a board held to the lightbox with three? screws. Careful - you don't even want to drop any as the chances are slim you'll ever see them again, except for big blue sparks as they short out a board when you plug it in. Once you take those out, you should be able to work the board around enough so you can at least see the bulbs. You'll need to snip a couple ties on the wire bundles to get enough slack to actually get in there with a jeweler's screwdriver and pop one end of the fuse bulb out. From there, you should be able to grab the free end of the bulb with some hemostats and pry it out.

Never said it was real easy. It can be a bit frustrating, but slow and easy till you see the plan. That's why I suggested you pick up a couple extra bulbs while you're at it. Just keep in mind you're working with old stuff and resist the urge to reach for the hammer. <G>

Good idea to also clean the bulb carriers so you get good contact. They get glazed over the years. I roll a piece of emery paper, grip it with the hemostats, and work it back and forth in the groove to shine the contacts up. Works well.

Meter lights are the same thing, only different. Once you get it all working, either replace the wire ties you snipped or just make sure there's no intereference with the dial cord or pointer.

Consider yourself lucky. I just did the lights on my QRX-6001 and had to pull the faceplate to get in on that one. Best I can figure, engineers hate consumers.
 
fair price ? yes.
good time to brush up on your electrical skills - familiarize yourself with Sansui internals and then move on once youve got it going because my thought is... for not too much more a qrx 5001, 6001 and 7001 are as easy to work on - im guessing - and will be the decoding you can live with for the rest of your life.
w.a.reid
 
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Oh yeah, my skills need some tweaking for sure. I've worked on radio/audio/TV stuff all my life, but those Sansui boxes are so CROWDED! A bit of extra patience is called for, I'm sure.
BTW, my 6500 does not get FM in stereo, did I see a post somewhere that a failed indicator light can cause that? Hope it's that simple...no stereo FM, no QUAD FM! (oops, I mean PL-II)
You're right, I MUST get a QRX-something, and I just may be getting one next Sunday for a good price. Owner THINKS it is a QRX-9001 but is not sure (it's still in his attic...somewhere), but right now I'd settle for anything with the VM decoder in it :>)
Happy 2010!
TB
 
Geez........A QR-6500 for $30!!! Man, I would be absolutely STOKED if a managed to pick one of those up that cheaply. It's true they don't have the full QS decoding but they were the top of the line back then, and you can always connect an decent external decoder to it. Plus you have the pre-outs (That many of the later Sansui Quad receivers lack) so you can connect a couple of much more Powerful power amps to it. I own a QRX-6500 (....which has been modded with pre-outs) and I love the sound of it and it has an excellent tuner and decent phono stage (Better than my 6001), and I paid Waaaay more than $30 for it. These early QR's are a lot more useable than many Quad fanatics give them credit for.........Sure I'd keep looking for a later QRX unit with thier much better QS decoding, but these early models are still excellent straight ahead hi-fi units. As I'm sure you'll find out yourself.
 
Well, Quadrockasaurus (cool handle!), I DID keep looking, and yesterday, Lady Luck smiled on me. At the Hazel Park Amateur Radio swap meet, I found a QRX-3000, clean inside and out, and working to boot...for $65! Yeah, the '3000 may be the "baby" in the Variomatrix family, but that's OK, it is a true-blue QS machine, and for THAT price, I'm thrilled to give it a good loving home.
It gets better...the guy that sold me the Sansui also had a nice Broadcast Electronics 250-Series 8-channel stereo audio console (or "board", as us has-been DJs called it), in near-perfect condition, all the modules and goodies intact inside, and I was really admiring it, thinking how tired I am of working with a Radio Shack "disco-mixer" in my little pirate...uh, I mean "independent" radio station. Well, since I bought the Sansui, the guy gave me a great price on the "board"...$50! Wow, how nice it feels after a long dry spell, to get hit with a double-whammy! :>)
OK, gotta get busy, I got a HUGE cable-stringing job ahead of me...
Regards from four corners,
TB
 
Wow......now I am jealous. A QR-6500 And a QRX-3000 from a flea market for pennies. Doesn't happen over here. I could look for YEARS here in Australia to find anything similar (...and I did until I found my QRX-6500 and a couple of years later my 6001) and I'd NEVER find it that cheaply...... By the way......you realize what you've got now. 2x4=8 channels i.e 7.1. If you wanted to you could set your system up as a combo retro Quad and modern surround setup using the QRX-3000 (Speaker A) for the front and rear and the 6500 (Speaker A) for the remaining channels. You could plug in your computer soundcard or outboard DVD player in addition to a Turntable or discrete Quad source. I'd still connect some decent Quad speakers on Speaker B of the 6500 as well, 'cause its a great unit and you can connect HEAP's of stuff to it.
This setup gives you a LOT of variety.:banana:

Cheers.
 
Australia? Man, I used to get up early to tune in ABC short-wave and listen to Dick Patterson play some great Aussie music! Hope to visit your land some day, I think I'd love it.
8 channels? Hmm, now all I need is three 35-mm projectors running in synch and a big curved screen! Nah, four channels are enough for the small room I listen in, but you're right, LOTS of room to experiment. (I have the Kenwood A/V set up for 4.0, no center needed, and the big front speakers seem to give enough bass without the "point-one")
I probably won't get the QRX-3000 hooked up and running before the week-end, and I'm kinda nervous...is this going to be anti-climactic after listening to Pro Logic II for over a year? PL II sounds REAL good on the local FM radio stations (they're encoded) and even with non-encoded CDs, it seems the steering is so fast and precise that it sounds like it can steer in several directions at once (of course, we know it can't really), plenty of separation and good imaging, even to the sides. But the loyal following I sense here in Quad-land for QS/VM has me salivating to hear what the '3000 can do...guess I'll know soon enough!
Regards,
TB
 
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