Truck451
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Does anyone know if any company has manufactured any Quadraphonic Broadcast Transmitting Equipment in a 2-2-4 pattern; that would have been equally compatible with Conventional 2-Channel Stereo and Quadraphonic Stereo?
Quadraphonic Broadcast Transmitting Equipment
- Thread starter Truck451
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Both CBS (SQ) and Sansui (QS) sold encoders to broadcast stations to matrix encode discrete four channel tapes into a compatible stereo form for broadcast. The encoders could also synthesize a stereo source to playback much like an actual encoded record would, stations could claim to be broadcasting quad continuously.
A discrete system was proposed by Lou Dorran and others using what was the SCA subcarrier in addition to the regular subcarrier used for stereo. Interest in Quad died out before a discrete system could be adopted.
A discrete system was proposed by Lou Dorran and others using what was the SCA subcarrier in addition to the regular subcarrier used for stereo. Interest in Quad died out before a discrete system could be adopted.
Maybe you mean 4-2-4 ? (4 separate tracks from discrete source-then matrix quad encoded -for matrix quad decoding ?)
The CBS and Sansui encoders when used to synthesize quad from stereo would qualify as 2-2-4, if actually decoded on the receiving end by the listener.
Truck451
New member
I am asking if any manufacturer made any enconders that were compatible with FM receivers of both the 2-channel and Quardaphonic systems, so that those with conventional 2-channel FM Receivers would not receive muted sound, like how the NTSC Television standard allowed for people who owned a Black and White Television set to still receive the Television signal in Black and White, rather than be "treated" to a blank picture if they did not own a Color Television set?
Matrix Quadraphonic encoded content can be heard when using just a
Stereo (or Mono) playback device:
A playback device can be:
FM (or TV or Satellite or AM) Stereo Receiver
CD (or DVD or Blu-ray or Vinyl LP) Stereo Disc
Compact Cassette (or 8 track or Open Reel or VCR) Stereo Tape Machine
The Involve Audio people make a Matrix Encoder:
http://involveaudio.com/product/studio-encoder-decoder/
Kirk Bayne
Stereo (or Mono) playback device:
A playback device can be:
FM (or TV or Satellite or AM) Stereo Receiver
CD (or DVD or Blu-ray or Vinyl LP) Stereo Disc
Compact Cassette (or 8 track or Open Reel or VCR) Stereo Tape Machine
The Involve Audio people make a Matrix Encoder:
http://involveaudio.com/product/studio-encoder-decoder/
Kirk Bayne
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That's why many vintage receivers have an FM single output in the back. It was designed so that a future quad FM "decoder" could be connected to it for discrete quad broadcasts, to detect that second subcarrier.
The Dorren System was, in fact, adopted, and is on the books at the FCC. Problem was that it came too late for any stations to care about adopting it. There was no longer a market for discrete quad FM.
Yes the proposed system was compatible with stereo and mono FM listening. That would of had to of been a major component of any system chosen. Aside from a few prototypes I don't think that any commercial equipment would of been produced as interest in quad dried up.
MidiMagic
2K Club - QQ Super Nova
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I know that Electro-Voice, Sansui, and CBS were selling encoders to radio stations. I have photos of them.
The 2-2-4 would be the matrixed record, the transmitter, and the decoder.
At the time, Dolby was making a record noise reduction system. It did not sell with record producers.
The CBS color TV system did leave the black-and-white user without a picture. We are lucky the Korean War cancelled its approval. It also took away the previously approved channel 1 for RADAR use (which is why TVs started with channel 2).
Digital TV also leaves the analog user without any signal. (Microsoft talked the FCC into rejecting the compatible HDTV proposal).
Digital TV also can't be transmitted as far. I got 14 channels with analog. I can get only 2 with digital. The others are out of range.
The 2-2-4 would be the matrixed record, the transmitter, and the decoder.
At the time, Dolby was making a record noise reduction system. It did not sell with record producers.
The CBS color TV system did leave the black-and-white user without a picture. We are lucky the Korean War cancelled its approval. It also took away the previously approved channel 1 for RADAR use (which is why TVs started with channel 2).
Digital TV also leaves the analog user without any signal. (Microsoft talked the FCC into rejecting the compatible HDTV proposal).
Digital TV also can't be transmitted as far. I got 14 channels with analog. I can get only 2 with digital. The others are out of range.
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Truck451
New member
A friend of mine who is a former ABC Radio Executive was once given a demonstration by Sansui right in his office at ABC's former headquarters on Avenue of the Americas, with equipment that Sansui had transported all the way to one of the top floors where his office was located, to demonstrate the differences between Monaural Audio, conventional 2-Channel Stereo, and Quadraphonic Stereo.
Once the demonstration had finished, he had determined that he could hardly tell the difference between conventional 2-Channel Stereo and Quadraphonic Stereo, he couldn't see himself and the American Broadcasting Company spending the money and efforts that would be required to convert their owned and operated FM Radio Stations to transmitting their signals with Quadraphonic Stereo, as well as for individuals to spend their own money for two additional speakers in order to actually be able to hear the FM Radio Station, their Vinyl Records, their 8-Track Cartridges, or their Audio Cassette all in Quadraphonic Stereo.
My friend had then politely told the representatives from Sansui (who were American, and had worked for the American branch of the company) "no thanks, but I hope you find another client willing to take on the Quadraphonic Stereo ambition". And so he had sent them on their way with their walking papers, and that was the very end of the prospect of ABC potentially converting their owned and operated FM Radio Stations to transmitting their signals with Quadraphonic Stereo.
One question that I have is, does anyone know if any automakers had made any Car Radios capable of receiving FM Quadraphonic signals?
Second, does anyone know if any Radio Station owners had experiemented with AM Quadraphonic signals to potentially rival AM C-QUAM Stereo signals?
Once the demonstration had finished, he had determined that he could hardly tell the difference between conventional 2-Channel Stereo and Quadraphonic Stereo, he couldn't see himself and the American Broadcasting Company spending the money and efforts that would be required to convert their owned and operated FM Radio Stations to transmitting their signals with Quadraphonic Stereo, as well as for individuals to spend their own money for two additional speakers in order to actually be able to hear the FM Radio Station, their Vinyl Records, their 8-Track Cartridges, or their Audio Cassette all in Quadraphonic Stereo.
My friend had then politely told the representatives from Sansui (who were American, and had worked for the American branch of the company) "no thanks, but I hope you find another client willing to take on the Quadraphonic Stereo ambition". And so he had sent them on their way with their walking papers, and that was the very end of the prospect of ABC potentially converting their owned and operated FM Radio Stations to transmitting their signals with Quadraphonic Stereo.
One question that I have is, does anyone know if any automakers had made any Car Radios capable of receiving FM Quadraphonic signals?
Second, does anyone know if any Radio Station owners had experiemented with AM Quadraphonic signals to potentially rival AM C-QUAM Stereo signals?
The Discrete Quad FM (Dorren system) was designed to work with Car radios
(and Home radios - mono clock radios, stereo radios and home Quad systems).
I've never heard about any Car radios with a built in Matrix Quad decoder (USA),
if (Dorren) Quad FM had caught on, Car radios would have additional circuitry
to decode the Discrete Quad broadcasts.
Quadraphonic AM was tried (via the C-QUAM AM Stereo standard, back in 2010):
https://www.quadraphonicquad.com/forums/threads/quad-radio-broadcast-this-week.12709/
Kirk Bayne
(and Home radios - mono clock radios, stereo radios and home Quad systems).
I've never heard about any Car radios with a built in Matrix Quad decoder (USA),
if (Dorren) Quad FM had caught on, Car radios would have additional circuitry
to decode the Discrete Quad broadcasts.
Quadraphonic AM was tried (via the C-QUAM AM Stereo standard, back in 2010):
https://www.quadraphonicquad.com/forums/threads/quad-radio-broadcast-this-week.12709/
Kirk Bayne
While I can't say with complete certainty I'm almost 100% sure the answer to both questions is a resounding no. Additionally the situation with AM stereo was botched by fighting over the best system and the FCC's slow decision. The FCC originally chose Magnavox but latter reversed their decision. The final decision was delayed for so long that it was too late for AM. One reason that AM stereo was so long in coming is that we already had FM stereo but AM was still much more popular, they wanted to keep the stereo advantage for FM. When AM stereo finally appeared, AM audiences were already shrinking. The AM stations liked to brag and hype the fact that they were broadcasting in stereo, but virtually all listeners only had mono radios at the time! I had a Plymouth Voyager Mini-van for awhile that had AM stereo, and it worked great, but try to find a stereo AM radio anywhere else! One by one AM music stations switched to talk or sports or flipped over to the FM band, the remained dropped stereo altogether. Stereo now gone no hope at all for quad.
Soundfield
1K Club - QQ Shooting Star
The thing I never understood about the proposals for discrete quad FM broadcasting in the US was what was anyone actually going to do with it? I assume the vast majority of US radio stations didn’t create original material and only played records, so what source of discrete 4ch stuff were they actually going to broadcast? I suppose they’d have just have ended up decoding matrix LPs and broadcasting those. But why bother, if that was all you were going to use it for? You’ve just moved a cheap matrix decoder from the consumer’s end and made him buy a very much more expensive receiver and put it in a studio feeding a much more expensive transmitter to achieve the same effect. Actually the net result would probably have been slightly worse in audio quality given all the noise and distortion artefacts of those complex proposed 4ch FM analogue systems.
I think that the hope from the discrete camp was that (discrete) quad would become as popular as stereo, even largely replacing it. The matrix proponents didn't want discrete FM broadcasting at all.
Soundfield
1K Club - QQ Shooting Star
Yes, but where was all this discrete source material supposed to come from?
It would be from new productions, assuming of coarse that quad was popular enough to warrant that. I suppose that they could also broadcast quad on an as required basis (turning subcarriers on and off) returning to regular stereo the rest of the time.
Soundfield
1K Club - QQ Shooting Star
Still not sure who would actually have been expected to create these new productions though - most radio stations didn't produce any original content did they? Would the record companies be interested in the costs of producing discrete quad versions of everything they made just for US broadcasting? Seems very unlikely.
But that wouldn't save on the enormous capital cost of installing a whole new transmission system . It would just annoy the consumer who would see that their expensive new receivers were rarely working in quad!
https://www.quadraphonicquad.com/forums/threads/original-rca-cd-4-quadradisc-announcement.26281/^^^
(Discrete) Quad albums/music sources - (2nd paragraph RCA2.pdf)
IIRC, the WEA group expected that ~50% of their albums would be
(discrete) Quad soon after selecting CD-4.
Of course, both SQ and QS encoded Quad albums could be decoded
and broadcast with the (Dorren) discrete Quad FM system.
Kirk Bayne
(Discrete) Quad albums/music sources - (2nd paragraph RCA2.pdf)
IIRC, the WEA group expected that ~50% of their albums would be
(discrete) Quad soon after selecting CD-4.
Of course, both SQ and QS encoded Quad albums could be decoded
and broadcast with the (Dorren) discrete Quad FM system.
Kirk Bayne
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