SANSUI QSD-2 question

I recently saw some archives about the Sansui QSD-2 decoder. I have a QRX-8001 that I love but am having problems that are most likely caused by deteriorating caps. I already had the pass thu's resoldered which fixed the major problems but the cap thing is rearing its head more and more. The local man who did the work has since retired and I am having a very frustrating time finding anybody who's willing to do the caps. I then heard about the QSD-2. This is the same vario-matrix decoder that is in my 8001 correct? If I understand correctly this is an outboard unit that could be used with a modern 5.1 receiver to achieve the same stereo to quad synthesizing results? This seems like an option since the inherent problems with the QRX's are amp related. If you could get the QSD-2 decoder to run through any 5.1 amp you'd be set for good, right?

Rick

Led9 said:

If you could get the QSD-2 decoder to run through any 5.1 amp you'd be set for good, right?

Rick

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Yep, that is EXACTLY what I am doing. The best of both worlds ... top-notch vintage quad decoder AND newer, more reliable electronics that sound better. Besides, with a decent newer A/V receiver, you get DTS and Dolby Digital as well. Mike.

Except that the QSD-2 will still be nearly as old as your 8001. If I were you, I would get in contact with Quad Bob and ask his opinion on this. The money that you will spend on a QSD-2 will just get you another old Sansui. But if you put that same money into restoring your 8001, you will have a virtually brand new unit (performance wise).
Lonster

Actually I emailed Quad Bob in regards to that last week but didn't hear back. My angle is that there is very little that can go wrong with a QSD-2 compared to my 8001. even if the QSD-2 needed work it would be alot less expensive and I would feel safer sending a relatively small unit like that to Bob to fix than trying to ship the 8001 through UPS twice. Now all I have to do is find a QSD-2 for sale. Anybody?

That makes sense. If money was not an issue, I would rather have the -2 than the 8001, but don't let shipping be a concern. I have shipped 4 heavy unit's back and forth to QB, using the same box each time, with FedEx ground, and not had a single problem. Bob knows how to pack.
What about loosing the amp section on your 8001 and just using the pre amp/decoder section?
Lonster

Actually I was wondering about that. I used the 4 channel tape outs to my 5.1 inputs but got only stereo. I guess that's a raw undecoded signal. is there any other way to use it as a decoder only?

Led9 said:

Actually I emailed Quad Bob in regards to that last week but didn't hear back. My angle is that there is very little that can go wrong with a QSD-2 compared to my 8001. even if the QSD-2 needed work it would be alot less expensive and I would feel safer sending a relatively small unit like that to Bob to fix than trying to ship the 8001 through UPS twice. Now all I have to do is find a QSD-2 for sale. Anybody?

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That was exactly my logic. The QSD-2 is MUCH simpler, and MUCH easier to recap. It seems like a LOT of extra work and expense to refurbish the rest of a QRX receiver JUST for the decoder section. There is really nothing special about the rest of the unit. Nice piece, don't get me wrong, but a total restoration will be more than the price of a QSD-2, which can be recapped for about $150. Bob Popham can do them as well, and you should always get a second opinion as far as I am concerned. The QSD-2 has a half-decent SQ section as well ... likely the same as in the x001 receivers. If you find a QSD-2, buy it. You won't be sorry ... ESPECIALLY if you get it recapped. It SOUNDS better than my recapped Tate, much more neutral. I was lucky enough to find a black one! Mike.

lonster said:

What about loosing the amp section on your 8001 and just using the pre amp/decoder section?
Lonster

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Not a bad idea, but you still have only 4-channel inputs. A more modern unit will have 5.1, and with a simple switch-box arrangement you can hook up your SACD and Multichannel DVD player(s) ... not to mention other quad components. Mike.

Led9 said:

Actually I was wondering about that. I used the 4 channel tape outs to my 5.1 inputs but got only stereo. I guess that's a raw undecoded signal. is there any other way to use it as a decoder only?

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Hello,
You would have to get Bob to do the main outs mod to get the decoded output. You might as well get the complete restoration done. You'll be glad you did.

Well there you go.
2 excellent options for 2 excellent units. And 2 excellent resto guys too.
If I remember my 'new' math correctly, that is Quad squared! :banana::banana::banana::banana:

Lonster

OK Mike and Lonster I've got a real crazy idea. For a quick fix the idea is to use the 8001 as a decoder only. What if you hook up 2 stereo headphone-to- RCA jack connectors to the quad headphone jacks and input to the 5.1 inputs? the signal is obviously the encoded signal and it's unamplified. Crazy but in theory it sounds possible. has anybody ever tried this?

Rick

HOLY CRAP! You're not gonna believe this but it worked! I went to radio shack and got the adapters and the headphone jacks do put out a useable encoded signal. The Sansui acts as a preamp and the cap problem is gone. No need for Quad Bob's output adapter! Why didn't I think of this before!

Pretty clever Led9 san.

Led9 said:

OK Mike and Lonster I've got a real crazy idea. For a quick fix the idea is to use the 8001 as a decoder only. What if you hook up 2 stereo headphone-to- RCA jack connectors to the quad headphone jacks and input to the 5.1 inputs? the signal is obviously the encoded signal and it's unamplified. Crazy but in theory it sounds possible. has anybody ever tried this?

Rick

Click to expand...

I do that on my QRX receiver, works like a charm... and the volume and tone contols all work as well

Led9 said:

HOLY CRAP! You're not gonna believe this but it worked! I went to radio shack and got the adapters and the headphone jacks do put out a useable encoded signal. The Sansui acts as a preamp and the cap problem is gone. No need for Quad Bob's output adapter! Why didn't I think of this before!

Click to expand...

Hello,
Way to go you guys, a great way to breathe more life into these dinosaurs. Once the word gets out I'm sure the price of the nonrestored QRX's on ebay will go up. Who knows maybe the price of the QSD's will come down now. I know there has always been an interest in an affordable (for us mere peasants) outboard variomatrix decoder. Who cares if it weighs fifty some odd pounds or more.

Now the question remains, how long before the electrolytic caps that aren't being bypassed rear their ugly heads? If Mr. Lee has been doing this for awhile maybe it's not an issue. One can only hope.

By the way Led9 the quad signals coming out are the decoded signals. The encoded signals, are the stereo signals going in. I'm sure that's what you meant to say, but I thought I'd clarify that for those that are still trying to figure this out. I know how confusing it was and still is at times trying to build the perfect beast.@:

I've been doing this for a couple of years now.... so far so good.