SQ Decoding without a Decoder

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https://worldradiohistory.com/Archi...idelity/70s/High-Fidelity-1976-08.pdf#page=37^^^
"Benjamin Bauer...suggesting that an SQ disc heard binaurally would be fairly accurately decoded."


IIRC, I've posted this info before, but now I have the WRH link. I tried this long ago
(using the Chase "Open up wide" SQ encoded song), listening with my
Koss/Sears K/6 headphones, I wasn't impressed (maybe it was the headphones).

Anyone else tried this type of SQ decoding using better headphones?


Kirk Bayne
 
https://worldradiohistory.com/Archi...idelity/70s/High-Fidelity-1976-08.pdf#page=37^^^
"Benjamin Bauer...suggesting that an SQ disc heard binaurally would be fairly accurately decoded."


IIRC, I've posted this info before, but now I have the WRH link. I tried this long ago
(using the Chase "Open up wide" SQ encoded song), listening with my
Koss/Sears K/6 headphones, I wasn't impressed (maybe it was the headphones).

Anyone else tried this type of SQ decoding using better headphones?


Kirk Bayne
I don,t think that just because you listen to SQ with stereo headphones that makes it binaural as far as I know the tracks have to recorded binaurally I don,t understand what he meant
Ron
 
Yes, it's unusual wording, if listening to SQ encoded content
(in stereo with stereo headphones) "decodes" SQ, just say that,
binaural and SQ are completely different things.


Kirk Bayne
 
https://worldradiohistory.com/Archi...idelity/70s/High-Fidelity-1976-08.pdf#page=37^^^
"Benjamin Bauer...suggesting that an SQ disc heard binaurally would be fairly accurately decoded."


IIRC, I've posted this info before, but now I have the WRH link. I tried this long ago
(using the Chase "Open up wide" SQ encoded song), listening with my
Koss/Sears K/6 headphones, I wasn't impressed (maybe it was the headphones).

Anyone else tried this type of SQ decoding using better headphones?


Kirk Bayne
I'm not sure if he was serious about SQ being decoded accurately in this manor or if it was more wishful thinking than anything else. That being said the ear is especially sensitive to phase differences heard through headphones. The various phase differences would make the sound-field larger than in plain stereo. It might be a bit of a stretch that front would be heard from the front and rear from the back through stereo headphones though. Koss phase 2 and phase 2+2 phones use phase to expand the sound-field. JVC 5944 phones have a phase switch for the rear, it makes a big difference. And don't forget the Fixler effect, that started it all and was the basis for EV-4.
 
I heard the front sounds change color differently from the back sounds. They smelled different, too.

Doug
 
I'm not sure if he was serious about SQ being decoded accurately in this manor or if it was more wishful thinking than anything else. That being said the ear is especially sensitive to phase differences heard through headphones. The various phase differences would make the sound-field larger than in plain stereo. It might be a bit of a stretch that front would be heard from the front and rear from the back through stereo headphones though. Koss phase 2 and phase 2+2 phones use phase to expand the sound-field. JVC 5944 phones have a phase switch for the rear, it makes a big difference. And don't forget the Fixler effect, that started it all and was the basis for EV-4.
I've found that the non-quad versions of some albums through the JVC 5944 headphones in phase reverse double stereo can actually be more interesting like Santana Welcome and Borboletta. It's as if a diamond or triangle is created where hard panned and true center sounds are emphasized which highlights the mixing and details you dont regularly notice. I was using them earlier in this way to compare the rear channels of some decoded SQ material against my Tate, these headphones really let you hear what the decoder is doing with the rear channels and exactly how much how much cancellation is being achieved.
 
This article by Bauer is in response to Ito 's that you could hear quad effect .

I tried this and it varies somewhat from the matrix sources , and par4ken is correct in that it was not supposed to be very accurate , but can be somewhat satisfactory.
Of course the correct type of earphones need to be tried . I found "open ear " type to be the better for this type of decode in either SQ or QS .
I made a tape of basic quad test tracks (2-3) of both matrices with approximately 7 or 8 popular SQ album tracks alongside the test tracks and the same with QS (also fr QS albums).

These I tried and some were better than others . There are a lot of listening factors to consider, but all in all there is some truth to these articles . (Which were both presented to the A.E.S )



I started a thread identical to this in 2017 .

You can find it on the "Matrix thread "on page 6 at the bottom.
 
https://midimagic.sgc-hosting.com/quadmuse.htm45. Quadraphonic Headphone Dichophony
"SQ Dichophony-Quadraphonic Earphone Listening" Benjamin B. Bauer,
Journal of the Audio Engineering Society 06/1976 V24 p. 387


I wonder if High End Electrostatic headphones would improve the stereo
headphone "quad" effect (it seems to me that the phase accuracy of the
headphone driver(s) would make a huge difference in the "quad" effect).

I'll pull out the Chase song on my demo SQ LP and try it with several
of my headphones/earbuds.

Found my previous post:
https://www.quadraphonicquad.com/forums/threads/stereo-headphones-dvd-sacd-dts-and-sq-encoding.4241/
Anyone have an all-software SQ encoder so that surround sound content
can be SQ encoded [to stereo] and thus made somewhat "quad like" for
stereo headphone/earbud listening (possibly from [stereo] songs saved in
a smartphone)?

Kirk Bayne
 
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Baier called it "SQ Dichophony". I tried it back when the article was written and it works. But the image is not the same as with speakers. I still use it.

dicohead.png


The following images happen in the head when listening to SQ and RM recordings in headphones. The upper images are identical to Bauer's except fir the shapes of the heads. I added the RM drawing after my own experiments.

I have also been able to hear RM with only 2 stereo speakers by placing them at about 75 degrees to each side. That does not work for SQ.
 
I can't find my encoded cassette tape that I used (via a walkman, at the time), but I had a number of tracks that tended to demonstrate the usage of the LB RB channels .
Tracks that were known by myself to show off the rear channels.
From memory alone , and bear with me as it was back in the late 70's , I'll try and list some excellent albums that contain some :

SQ :
From Chicago 1 "Beginnings"
Ten Years After (there are more than one) , so I forget, exactly which one.
Deep Purple -"Lazy"(fr Machine Head)
Manuel Gottshing a track fr. -Inventions for Electric Guitar,
Pink Floyd -Atom Heart Mother Suite fr A.H.M. and "On The Run " fr. Dark Side Of The Moon,

And a few others from Columia/CBS.

-------------------------

For QS :
Tracks fr. Larry Fast's ELECTRONIC Realizations....
Tracks from 2 Steely Dan albums , and Joe Walsh" Meadows"fr Smoker You Get.....
and Harvey Mandel , track( I don't remember though).fr Get Off In Chicago.
and a couple others.


Anyway , my point is if you want to be subjective with a decent demonstration , a few tracks should be tried . :)
 
Anyone else tried this type of SQ decoding using better headphones?
I tried it with Sennheiser HD424. Only when I led my imagination run free, I would vagely hear something resembling that. There is no acoustical basis for it. The phase-relationship between the two ears in real life behaves similar to a delay-line. The fixed phase shift of +90 and -90 degrees in the SQ-coding is something completely different. So why would it work?
 
So...(a little OT):

Has an all software SQ encoder ever been developed/written?

Discrete surround sound content could then be SQ encoded for
stereo headphone listening (I don't know if the audio data reduction
that may be used when songs are saved in Smartphones would
disrupt the surround effect).


Kirk Bayne
 
Baier called it "SQ Dichophony". I tried it back when the article was written and it works. But the image is not the same as with speakers. I still use it.

View attachment 56059

The following images happen in the head when listening to SQ and RM recordings in headphones. The upper images are identical to Bauer's except fir the shapes of the heads. I added the RM drawing after my own experiments.

I have also been able to hear RM with only 2 stereo speakers by placing them at about 75 degrees to each side. That does not work for SQ.

@MidiMagic
Looking at those dummy head diagrams , midi,....pretty much confirms what I was receiving with position placement when demonstrating my own tape recording for listening.

And I even hear something " quadlike" similar with my mp3 with buds.

Thanks 4 that :)
 
I tried it with Sennheiser HD424. Only when I led my imagination run free, I would vagely hear something resembling that. There is no acoustical basis for it. The phase-relationship between the two ears in real life behaves similar to a delay-line. The fixed phase shift of +90 and -90 degrees in the SQ-coding is something completely different. So why would it work?

Look at where the LB and RB images for SQ are in the head images.

This is probably the result of the auditory system trying and failing to make sense of the sounds it heard. Also notice where the F image is. The information from the pinnas (earflaps) is gone.

Baier called it "SQ Dichophony".

Oups! Tupogoofical errer! Bauer.

Also note that I was able to hear almost the full Dolby Stereo on a film while in a theater that had only the three stereo speakers behind the screen by sitting in the first or second row and facing forward.
 
Last edited:
Back to the original topic, when I first heard of quadraphonic sound (although the name hadn't even been generally agreed on), I stuck two really cheap speakers beside my couch, and just the difference in the sounds coming from them made a surround effect. I'll never claim it decoded anything, just that it was an interesting experiment that I found enjoyable.
 
So...(a little OT):

Has an all software SQ encoder ever been developed/written?

Discrete surround sound content could then be SQ encoded for
stereo headphone listening (I don't know if the audio data reduction
that may be used when songs are saved in Smartphones would
disrupt the surround effect).


Kirk Bayne
There is a script for Audition for SQ encoding. Look here for the script matrix encoding software (windows)
I'm not sure that I would bother to encode just for headphone listening though.
 
I doubted that un-decoded SQ material would produce any surround effect over headphones so I've just tried it. Absolutely no perceptible effect whatsoever from a variety of recordings. What a surprise.
 
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