Young quadraphiles?

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QQ Lifetime Supporter
QQ Lifetime Supporter
Apr 23, 2019
Greenville, SC (via NJ, Philly, ATL & SoFL)
Not knowing ages of members, I cannot tell if younger people know about 1970s quadraphonic systems...

This weekend I set up some powered speakers for my 20-year old son’s computer station. He then said, dad how can I have music all around?

That gave me an idea. We plugged in a Sansui QSD-2 decoder I was not using, ran line level cables and set up a powered modern-day “stereo boombox” as back channels.

He was blown away. He spent an entire Sunday — and since — revisiting his fave albums (from Stevie Ray Vaughn, Eric Johnson, Handel, Bach, Pink Floyd, Men I Trust, Muse...) and trying out the Sansui’s “Hall, QS and SQ” settings.

I have to say, realistic or not, the sound is gorgeous.

I gave him articles on how matrix systems work (he is a math major) and he seems very intrigued by the whole concept.
You do realize, as a parent, you should not give your kids their first taste of crack. :LOL:


1K Club - QQ Shooting Star
Dec 29, 2011
Essex, UK
I took a short video of the ‘scope’ on my Technics SC-2500 receiver. After looking at it more I ‘think’ how it works is that it has the 4 small F/B sets of LED’s and also a EL panel behind that is separated into 4 sections that are frequency modulated. I finally figured this out by looking at it turned off and noticing that in the back of the display there was a white square that was roughly the same dimension as the display. This would explain why it gets so bright when the volume is turned up as the LED’s alone couldn’t produce that much light. I guess they could also be using 4 individual lights behind the square that are dimmable but I think that would be too easy to pick out.

I really don’t know if this is indeed how it works but it is my best guess. It is weird that Technics didn’t use this on any other receiver as far as I know. On this video the audio is very low but you can hear it and see how the scope does it’s thing.

Those types of display were never very sophisticated. Something like a reflector, four lamps, an opaque diffuser and a plastic Fresnel lens.
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400 Club - QQ All-Star
Mar 25, 2014
I wonder how much the acoustically treated room cost to have designed and built, it probably exceeded the cost of the kit! :unsure: I'll buy a lottery ticket :rolleyes::ROFLMAO:
The ceiling looks like it was stolen from the Cloud City set from The Empire Strikes Back. Heck, one of those slabs on the wall might even be Han frozen in carbonite for all we know!


Well-known Member
May 30, 2011
I... did not exist in the 1970's. The formats are fascinating technically - and the failure of any to succeed certainly a loss. If I see one one in the flesh, I would likely work out what it is but... I've never seen one! Anyway; I'm trying to suck the kids in; and they were born this century... one I saw dazed processing Pink Floyd's Dogs, being performed live by Roger Waters, the other day...