Sansui QRX 7001 and 4 Ohm speakers?

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Hum... yes of course, yes I have seen pictures of where the control boards are , and yes again, you almost have to split it open completely, then you can adjust it or verify the voltage coming out for the quad thing... man it must sound like heaven with your tape reel, bit jealous here! hahahaha

The 8001 and 9001 are MUCH worse to work on.
 
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I brought it home :) Can't believe how heavy it is! The variomatrix board works fine, it is amazing how incredible the surround mode sounds! Couldn't check CD-4 but if I'll worry about it whenever I find the patience (and funds) to set it up properly.
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Very nice! Congratulations. I would be surprised if the demodulator doesn't work, but it isn't the end of the world if it doesn't. CD-4 can be a real pain in the ass, even though some people think they know how to do it properly ... and you can always get a stand-alone unit if you really want to head down that rabbit hole.

I am out of here now, but here is my last piece of advice. Try a stand-alone phono preamp with your Variomatrix (the SQ decoder is quite good too). You will get improved matrix decoding from a newer preamp. I use a Rega Fono, but I have used others (Cambridge Audio, ProJect, Tonar Vinyline, Graham Slee) with great results.

Enjoy!
 
hey guys - i upgraded from a 6001 to an 8001.. at least I am hoping its an upgrade... I don't have it yet - its in transit, but I'm curious about the 8001 and 9001 being problematic comments.. its had a complete restoration with all the upgrades from QRXrestore.com so I am hoping I won't see any issues that you are referring to.. what troubles have you experienced with them..
 
Finally got it all set up.. sounds amazing. the QS Synthesizer is awesome... crystal clear, warm sharp sounding. I do think I have an issue with my turntable playing CD 4. Symptoms are the same as my 6001, and I think its the handiwork of the previous owner. He replaced the RCA cable plugs and I think he at least put them on backwards. When I plug Red to right, White to left it does not detect the carrier signal, swap red to left, white to right and it detects it, but really poor and only comes in on one side. My 6001 did the same exact thing and I thought it was the receiver, now I think its the Turntable. Going to start by replacing the RCA cables completely and go from there.. Going to test with a friends turntable as well. Just odd that Red to right, White to left sounds terrific in stereo as well as SQ.

Turntable is a Technics SL 1800 MKII with Audio Technica TP112Sa cartridge w/ a ATN 12S Shibata stylus.
 

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Very cool! The 8001/9001 are gorgeous receivers! The CD-4 issue sounds strange but I can't help much, I get discrete quad on SACDs, CD-4 always seemed like a very delicate thing to setup. Not to mention the carrier on used CD-4 LP being damaged. (Actually, maybe that is the issue? Did you try a few records or just one?)
 
I get same results on multiple CD4 albums, and now I'm seeing same thing on my new 8001, which has had a full restoration, as I did on my 6001. Leads me to believe it's something with my turn table.
 
I am out of here now, but here is my last piece of advice. Try a stand-alone phono preamp with your Variomatrix (the SQ decoder is quite good too). You will get improved matrix decoding from a newer preamp. I use a Rega Fono, but I have used others (Cambridge Audio, ProJect, Tonar Vinyline, Graham Slee) with great results.

Enjoy!

It's been a while, but I have just hooked up a stand-alone preamp - the MoFi StudioPhono - and am listening to my quad LPs. You were so right, they sound so much better!!! The channel separation is now really stunning! I had one LP, a Japanese pressing of Santana's III which sounded horrible through the QRX phono input - there was definitely something wrong with the midrange, vocals were recessed and guitars sounded weird. With the new preamp it sounds glorious! The same thing with the "Welcome to the world of quadrophonic sound" CBS sampler, I was never happy with the four corners of the church of San Marcos in my living room before, the image was always a bit blurry - and today I just heard them beautifully. That was a great piece of advice! Thanks!
 
Question about connecting a phone pre-amp.. the turntable connects to the pre-amp, but does the pre-amp connect to the AUX or Phono on the receiver? Seems it should go to AUX since the the whole idea is to bypass the phone pre-amp, but doesn't that also bypass the receivers quad decoders?
 
Connect the phono preamp to the AUX input, NOT the Phono input. You can still use the receiver's matrix quad decoders, but not the CD-4 demodulator.
 
That makes sense thanks... Does that also increase the power ie: volume? or is that just dependent on the pre-amp you buy? That's the one thing I was disappointed with the 8001, Radio, AUX, Tape 1\2 all have plenty of power, the phono pre-amp volume is only so-so.. good enough with the volume at 7, but I didn't expect to have to...
 
That makes sense thanks... Does that also increase the power ie: volume? or is that just dependent on the pre-amp you buy? That's the one thing I was disappointed with the 8001, Radio, AUX, Tape 1\2 all have plenty of power, the phono pre-amp volume is only so-so.. good enough with the volume at 7, but I didn't expect to have to...

This depends on the power output of the onboard preamp vs the outboard preamp - in my case the outboard one has a stronger signal and overall I am not listening at lower volume settings than when using the PHONO input. To be able to compare these two situations you would need to know the output level of the onboard preamp.

However, if you need to turn it up to 7 to be able to enjoy the music then there is probably something wrong with your built-in preamp.
 
I think i overstated my intent... My setup is in my basement - pretty open area room, about 25'x14'. when listening to the phono, I have to turn the volume to 7 to be "loud", not just enjoyable. Radio or CD player can be set to the 4-5 range...
 
Sorry I can't add any tech info here, but just happy to see someone enjoying the QRX-7001. Bought mine new in Japan, 1977, but had it completely rebuilt a couple years ago after sitting in storage (garage) for too many years. Works great again! Teamed up with my Sansui and TEAC 4-channel tape decks.
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TEAC A3340 and Sansui QS5050-3.jpg
 
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