:: sq quadraphonic ::

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Thanks Duo for your reply ...

I agree if quadraphonic is original and cool and more musicality than dolby surround, its not add anything to the music [for QS matrix I think] ......

But why everyone leave them? :confused: And I've browsed the net and I need more info about the DIY Quadraphonic ....

Regards:
ragil.hastomo
 
Well, I dunno why Quadra never caught on. I've never really listened to it but I plan to read the theory on it and build a decoder as one of my "infamous" surround projects to see if I like it. Right now, I use a form of Dolby Pro-Logic I designed myself and am still adding on to. It is designed to get 7 completely discreet channels out of only two inputs. So far I've built the system up to two front speakers, a center, and a set of rear mono. But I'll soon be making the box that modulates the rear channels into stereo and makeing a set of side channels that are panned out from a summing of the rear and front of thaqt side to help enclose the listener. This way there will be on center speaker, the regular front stereo speakers, a speaker on each side wall in line with the listening chair and a set of rear speakers, all producing different sounds and parts of the music. This system also works perfectly for movie surround sound and is not digital nor active so it doesn't color the music at all except for the coloring of the passive parts which is very minimal. The complete decoder will be constructed out of Hammond broadcast transformers, resistors, capacitors and maybe a couple of transistors. But absolutely no ic's or filters of any type. My current system already sounds much better than any dolby pro logic or home surround sound box for that matter because of the high quality parts I have used. If you like, I can post a diagram later once I have completed the engineering and testing which may take a few weeks but will be worth it...
 
An interesting tidbit of info that few realize. When Dolby came out with the first cinema stereo processors they liscensed the 2/4 Encode-decode scheme of the Sansui QS matrix system. I've seen many 2/4 decoder cards in these early Dolby cinema processors. They must have had some sort of agreement with Sansui as to liscensing as the QS logo was on every card for quite a few years.
Mark
 
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Joined 2002
Get a load of this little item:p
It's a Sansui QS-800A
I also have the "Operating Instructions & Service Manual", complete with schematics and parts lists.:nod:

It's about 30 pages.

Anyone Interested?
Rodd Yamas***a
 

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Man, I used to fix those Sansoupis back in the early 70's! Worked at a hi-fi service center for a large chicago Hi-Fi store chain back then. Those darn plastic tab power output transistors used to literally melt apart! Some of the more expensive models had TO-3 style outputs. Then came along the Pioneer SA-1000(er somethin like that) receiver at 250 wpc! Wouldn't even fit on my bench! The Pig of all Pigs.....
Mark

That might ahve been SX-1000 Pioneer. I think thats how much it cost too.
 
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Joined 2002
The Sansui QS-800 could play the 4 main types of quad that was available back in the 70's. It is a quad extension to a receiver or integrated amp.

It has what Sansui calls QS Vario-Matrix which can synthesize 4channel from stereo, decode both Sansui's QS Matrix encoding and CBS's SQ Quad encoding. Plus it has four 45W amps for discrete quad (discrete material was only available on 8 track tape and reel-to-reel). QS or SQ encoded quad was available on disc or FM broadcast.

I use it now for my computer amp.
Rodd Yamas***a
 
The Orig Hafler or shall i say Dynaco Quad adaptor used a power resistor i think about 10 ohms that was in series between the two Connected grounds of the rear speakers and the Amp speaker grounds. this system did not work with BTL or Bridged type of Amps as a Common ground on the amp was required. In Addition an LPad Attuator was used on the rear speakers to adjust the rear speaker levels. Crude but effective Quad.
 
Actually, that common ground resistor thing was an idea stated in an earlier thread. A person wants to know how he can have the headphone jack disconnect the speakers as he connects the headphones. Someone suggested that for the headphone resistors he should connect the headphones directly to the amp outputs and the common ground them through a resistor. I immediately protested saying that this wouldn't save the headphones from signals that were out of phase in the channels and panned left or right. It would basically work like a hafler matrix and let the headphones have direct power from the amps and there wouldn't be a very good stereo image.

I guess my idea was pretty good for never knowing that anybody ever used a common ground resistor to make a matrix. I guess that works but you would still have some stereo image at the rear. Who knows, maybe stereo imaging in the rear is a good concept to try.
 
Let me try and recall from heck like the mid 70's. If i remember Right the Image from the Rear speakers highlighted any info that was out of Phase Between channels and attuated info common to both channels, like Voice was almost not there, but info that was only on one channel was bled into the other but had an out of phase quality to it similar to having the speakers out of phase. also Bass from the rear was like the Voice attuated. with all 4 speakers playing the overall effect was Nice and on some music most notably Electronic Music almost 3D Holographic, Hope this helps as i cant remember any more about that Quad adaptor. This sure did jog my memory in a good way Brings back the Good old days of My Dynaco Stereo 400 pwr Amp Pat 5 preamp and I think the FM6 tunner with my Bose 901's in the rear and JBL L-100 in the front that were upgraded to the Altec Lansing Voice of the Theator yup the Big Green Box ones with the Huge horn on top.

BTW the Dynaco stereo 400 always kept blowing outout transistors.
 
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Joined 2002
Hi Ragil,

Sometime next week I'll take it to work and scan it into an 11" X 17" .pdf file. Then I'll have to email it to you.

While taking a better look at the schematic, I realized that there are two boards that are shown as blocks. The schematics for these two blocks are omited. I'm thinking that these are the decoder boards because there is no mention of them in the parts lists or board layouts.:bawling:

I will send the schematic anyway, and you can see what you can see.:bigeyes:

Rodd Yamas***a
 
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