On Sun, 1 Jul 2018 00:17:08 -0700 (PDT),
wrote:

On Friday, June 22, 2018 at 4:35:46 PM UTC-4, wrote:
This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in
parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny

Chuck
I took a leap of faith assuming that if the second 4 channel board fit mechanically it would work electronically. And to my great luck and surprise it did! I'm not sure if I now have two earlier or later versions of the quad boards in there now but they were apparently compatible. And the retrofit worked quite well too. The very slight "popping" noise that I had previously heard out of the rear speakers was gone, the dead rear channel is restored, and in fact the sound was clean through all the speakers. I have never heard "4 channel" out of this unit so this is going to be thrilling uncharted waters.

Now I do realize that no one broadcasts 4 channel analog any more and I also know that sources to reproduce it including any records, or tapes, etc are probably few and far between anyway. But I was wondering if you might have any information on that?

The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.

I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.

So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny
Lenny,

The Sansui surround system was called QS. It wasn't very successful.
I noticed a few QS records on EBay including one by a Chicago folk
singer Bonnie Koloc on Ovation records. I bought this album in the
early 70s and, if you like poppy folk music, it would make an ideal
test record to experience QS quad . Chuck