When surround sound first appeared in the late 1960s, various systems were developed by different companies and individuals for the purpose of using the existing phonograph record, recording tape, and stereo radio technologies for surround sound. Of course, the worst thing possible happened. Each company created a different system and patented it, hoping to be the winner in the marketplace. The result was chaos.
All of the surround sound systems are based on either a multiple-track recording method, or some kind of encoding and decoding system. Those using an encoding and decoding system have a decoder inserted into the sound system at some point. Most systems insert the decoder after the pre-amp. Others insert it after the phonograph pickup cartridge, or between the power amplifier and the speakers. Read the instructions to find out where the decoder belongs. Of course, all of the components after the decoder must be duplicated, so there are four channels.
Note that some of the systems are now totally unavailable. For example, none of the experimental FM quadraphonic systems would be in use today, because the Federal Communications Commission (FCC) never approved any of them. So decoders for these systems are totally useless today.
On the other hand, quadraphonics is not dead. It is transformed. In 1976, a system appeared that outperformed all of the old quadraphonic systems. It is Dolby Stereo, originally created for the movie Star Wars. It solved two of the problems the old systems could not solve: Placing a sound image to the side of the listener, and keeping the front center vocalist out of the back speakers.
The old systems were withdrawn from the market, as Dolby Surround took over the home market in 1982. At that time, "quadraphonics" was renamed as "surround sound." Many more recordings have been issued in surround sound than were ever issued in all of the old quadraphonic formats combined.
THE SIMPLE APPROACH TO QUADRAPHONICS
Quadraphonic recordings can be divided into these groups. Each needs its own player or decoder:
Get only the decoders and players you need, and use multiple input selector switches to select the correct devices.
Quadraphonics can be added to an existing surround sound system with a 6-channel discrete input.
More on Quadraphonic Compatibility
Build the UniQuad UQ-1A Quadraphonic Decoder
The Quadraphonic Systems page is a table containing all known encoding systems, with information on how they work and how you can play them today. The stylus modulations in the record groove are shown, so you can visualize the phase relationships. Tape and stereo radio used the same matrix encoding means, but the phase relationships were not so obvious. The Poincaré Energy Sphere is used as a tool to show the distance (and separation) of any two of the modulations.
The following table contains a list of all known systems, with brief information about them. A minus sign denotes lower compatibility.
SURR denotes how accurately the system places musical parts.
HALL denotes how well concert hall ambience can be reproduced.
SYNTH denotes how well a surround effect is produced from stereo recordings.
MONO denotes how compatible the recording is in mono playback.
USE denotes the relative abundance of recordings of each type.
|SCHEIBER AND SANSUI QS||QS, RM||Regular matrix||RM||Square||DD EV DQ DS RM HT TP||0.5||0.5||0.7||0.0||#2|
|THE DYNACO DIAMOND||DD||Regular matrix||RM||Square||QS, EV DQ DS RM HT TP||0.5||0.6||0.9||0.0||(#9)|
|ELECTRO-VOICE STEREO 4||EV||Regular matrix||QM||Front||QS DD DQ DS RM EU HT TP||0.6||1.0||1.0||0.0||#5|
|DYNAQUAD||DQ||Regular matrix||QM||Front||QS DD EV DS RM EU HT TP||0.5||0.7||0.9||0.0||#9|
|CBS SQ||SQ||Phase matrix||PM||Wide||EU UQ||0.6||0.2||0||0.1||#3|
|CBS SQ 10-40 BLEND||SB||Phase matrix||PM||Front||EV- DQ- SQ UQ||0.8||0.4||0.2||0.1||(#3)|
|DENON UMX, BMX, and UD-4||UM||Uniform matrix||UX||Square||HM-||0.3||0.5||0||0.8||#8|
|JVC RCA CD-4||C4||Discrete||CD||Square||-||0.4||0.4||0||0.8||#4|
|ELECTRO VOICE UNIVERSAL||EU||Phase matrix||PM||Front||EV- DQ- SQ UQ||0.7||0.5||0.3||0.1||play|
|BBC MATRIX H||HM||Uniform matrix||UX||Square||UM-||0.5||0.5||0.4||0.9||#10|
|BBC MATRIX H REVERSED||HR||Uniform matrix||UX||Square||-||0.5||0.5||0.4||0.9||#11|
|UNIQUAD EQUAL SEPARATION||UQ||Phase matrix||PM||Square||EV- DQ- SQ EU||0.8||0.5||0.3||0.1||none|
|DOLBY SURROUND||DS||Regular matrix||QM||Front||QS DD EV DQ RM EU HT TP||1.0||0.5||0.4||0.0||#1|
|DENON BHJ AND UHJ||UJ||Ambisonic||UX||Square||UM HM QS- DD- EV- DQ- DS- RM-||0.4||0.4||0.3||0.9||#6|
|HEXAPHONIC TRIDEE||HT||Regular 3D matrix||QM||Octahedron||QS DD EV DQ DS RM TP||0.5||0.4||0.5||0.0||#12|
|TETRAPHONIC 3D||TP||Regular 3D matrix||RM||Tetrahedron||QS DD EV DQ DS RM HT||0.5||0.4||0.5||0.0||play|
|COMPATIQUAD||CQ||Phase matrix||PM||Front||QS DD EV DQ DS RM SQ EU UQ HT TP||0.6||0.6||0.7||n.a.||play|
|PHASE LOCATION||PL||Panless matrix||n.a.||Square||SQ EU- UQ-||0.8||0.4||0.0||0.0||none|
|SPHEROUND SOUND FIELD||SF||Regular Matrix +||QM||Tetrahedron||QS DS DD EV DQ RM EU HT TP||1.0||0.7||0.8||1.0||new|
What you need to play these recordings depends on what you want to achieve. Several levels of complexity are possible:
* The page author has used these systems at various times.
The use of the Dolby Surround, RM, and SQ decoders, with phase inverters, summing networks, and speaker amp source switching is probably the easiest way to handle the greatest number of matrices with only a small investment. It is not perfect, but gives results near the intended ones. The following system uses 10 speakers (8, if you aren't interested in 3-D), and handles all of the above systems except CD-4:
The following tables describe the operation of the author's system.
|QS, RM||(TSF RM RVB)||TWS RM RVB||.41||(TWS RM RVB)||TWB H RM RVB||.41||(TSB RM RVB)||OFF||NORM||1.0|
|DD||TSF RM RVB||(TWS RM RVB)||.41||TWS RM RVB||(TWB H RM RVB)||.41||TSB RM RVB||OFF||NORM||1.0|
|EV||(TSF RM RVB)||TWS RM RVB||.2||(CQ TWB RMB)||TWB H RM RVB||.8||(TSB RM RVB)||OFF||NORM||1.0|
|DQ||(TSF RM RVB)||TWS RM RVB||0||(CQ TWB RMB)||TWB H RM RVB||.58||(TSB RM RVB)||OFF||NORM||1.0|
|SQ||(UH CQ USQ)||UMXW H CQ USQ||.05||(USQ)||XHB CQ USQ||.05||(CQ USQ)||OFF||NORM||1.0|
|SB||(UH CQ USQ)||UMXW H CQ USQ||.1||(USQ)||XHB CQ USQ||.40||(CQ USQ)||OFF||NORM||1.0|
|UM||HF UMX||(HL UMXL)||0||UMX SQF H||(HD UMX)||0||H UMX||OFF||NORM||0.95|
|EU||(UH CQ USQ)||UMXW H CQ USQ||.2||(USQ)||XHB CQ USQ||.41||(CQ USQ)||OFF||NORM||1.0|
|HM||HF UMX||UMXW H CQ USQ||0||UMX SQF H||TWB H RM RVB||0||H UMX||OFF||NORM||0.8|
|HR||HRF||UMXW H CQ USQ||0||UMX SQF H||TWB H RM RVB||0||HR||OFF||NORM||0.8|
|UQ||(UH CQ USQ)||UMXW H CQ USQ||.32||(USQ)||XHB CQ USQ||.32||(CQ USQ)||OFF||NORM||1.0|
|CS (& S-180)||(UH CQ USQ)||UMXW H CQ USQ||.05||(USQ)||XHB CQ USQ||.05||(CQ USQ)||OFF||REV CS||1.0|
|UJ||UH CQ USQ||UMXW H CQ USQ||0||TWS RM RVB||TWB H RM RVB||0||H UMX||OFF||NORM||0.7|
|TP ‡||(UH CQ USQ)||UMXW H CQ USQ||.32||(TSS)||(TSS)||0||TSS||DSV ‡||NORM||0.9|
|CQ||(UH CQ USQ)||UMXW H CQ USQ||.2||CQ TWB RMB||XHB CQ USQ||.41||(CQ UQ)||OFF||NORM||1.0|
|CQ with DS||DS †||DS||0||USQ||DS||0||OFF||OFF||NORM||0.8|
|PL||UH CQ USQ||UMXW H CQ USQ||.9||USQ||XHB CQ USQ||.3||CQ USQ||OFF||NORM||1.0|
|SF||(TSF RM RVB)||TWS RM RVB||.2||(CQ TWB RMB)||TWB H RM RVB||.6||(TSB RM RVB)||DSV||NORM||1.0|
|- Channels with positions in parentheses can be switched OFF, or set to TSS if
- Channels set to OFF can also be switched to TSS if the position is available.
- For matrix H or HR, the HF and HRF positions are better than H on the F switch. Use H on the F switch for UJ.
† OFF on the author's DS system, which won't drive the author's front (center) speaker properly.
‡ Use the SQ positions on the Metrotec decoder instead of the I/Q positions.
|* Experimental position.
** This position is on the receiver, and affects all ** channels simultaneously.
† This position is derived from the Tandy Surround front outputs inside the switch box.
†† This position is derived from the Tandy Surround front outputs inside the switch box, with a fixed blend setting.
‡ Dolby Stereo front (dialog) output not used on the author's DS system: The author's front (center) speaker needs an equalization curve different from that of the main speakers. Since the surround receiver can't provide separate equalizations, the front speaker is always fed from the switchbox.
QUADRAPHONIC AND SURROUND INDEX PAGE
UniQuad UQ-1A Quadraphonic Decoder
Encode surround sound with your mixer
UniQuad Phlazex Quadraphonic Encoder
Stereo and Surround Sound
Mixing your own music