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Amplifier Problems With a Sansui QRX-9001

If so, I don’t think I’ll get into it now. It’s just a slight inconvenience on the rare occasion that I listen to it in 2-ch. And I’m absolutely loving having her back! An unbeatable listening experience!
 
It was a royal pain to pull the thing out to repin it, and I just hate to do that. Things can go wrong quite quickly with all that entails. Sometime I’ll get around to doing it, but I don’t think I’m quite ready to tear back into that.
 
I'll admit I hadn't looked to see if that Omron relay was still available, but I'm not surprised it is obsolete. We"re seeing a lot more of that, and really, what can we expect 45 years later? I'm surprised at the availability of all the things we still can get for repair and rebuilding work.

This has been an informative thread, some great troubleshooting advice by @Overundr1. And good to see yet another 9001 restored to it's proper glory.
 
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Yeah, I’m overjoyed to have her back in great working condition! And the parts availability is troubling. I am thankful to the parts availability that is still around, but it’s becoming more and more scarce. Guess we’re going to have to start getting creative.
 
Well done. I'm curious if you replaced the red axial LED's over the bank of pushbutton switches? Looks super bright/saturated in the picture (moreso than I'd expect the stock LED's, which are pretty typical Iow output mid 70's LED's) but maybe that's just the camera used.

Quad is an odd thing. It failed to impress (enough) to really take off when new, despite much effort and money spent - particularly by Sansui - who was then at the forefront of advancing four channel matrix technology and it's hardware.

If you use the synthesized surround mode from good 2 channel material (i.e., not compressed sources like MP3) you absolutely will hear things you never did before in the stereo mix. I've gotten hooked on it, though at times maybe it makes me try to focus too much, listening for those little "Easter eggs" instead of just relaxing and listening for mere enjoyment. Do try to tune your ear though to detect those little bonuses in the music that magically become apparent with 4 channel.
 
I did not replace them. They are excessively bright. I’ve been trying to think of a way to dim them a little. If you have an idea on how I’d much appreciate it. I had the idea of adding resistors, but didn’t know if they’d dim or just fail to function properly. I bought her on eBay awhile back. It was supposedly fully restored and recapped, but it was not. It was in terrible shape aside from the looks. I believe all the seller had actually done was replace the lights, and incandescents with LEDs.

I do absolutely love quadraphonic sound. I got a Sansui QRX-5500 passed down to me, and loved it. Did some research and found the Sansui QRX-9001 and eventually got the money together to buy one. And yes I do listen closely to the details, at times exhausting myself doing so!
 
Strange those are so bright. On my 9001's they are clearly visible when on, but certainly not high output like some of the LED's available now. They are an usual LED stype, long since obsolete. Finding axial leaded types now is not so common, and if any need replacement, they'd all have to be done in order to match, as the factory LED's are nowhere to be found, save for on a parts unit.
 
Huh, yeah compared to the FM stereo LED they’re about 5 times brighter. It’s especially bad when I’m in CD-4 with CD-4 radar. In that mode they’re almost bright enough to light up the room on they’re own, obstructing some of the text.
 
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That difference in brightness is not right. I suspect maybe they were replaced before you acquired the unit. If they are modern high output devices (in the 1000's of mcd range of light output versus a couple of hundred mcd at most for the factory originals), then dropping resistors probably won't normalize their light output to an acceptable level. Probably will need to replace those (again) with more suitable parts.

These are roughly T-1 form factor in diameter, and are sized to fit the stamped holes in the front sheet metal frame panel perfectly. They have a fairily short length from base to viewng end, further shortened by the axial leads that enter the encapsulation at the sides rather than the rear. They are all on a small PCB retained to the front frame panel by plastic push rivets, and there isn't much depth behind the panel to work with there, which is undoubtedly why the factory chose the part originally used.

Let me see if I can scrounge up a picture.
 
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