A query of how to do something technical led to what is believed to be the first use of matrix quadraphonics for sound effects in a live stage play.

We had the ghostly voices coming from various directions, thunder rolling across the auditorium, and other sound effects placed over the stage to match events on the stage. The sound effects were quite effective.

Disclaimer: Since I have lost track of all of the participants in this play, since many of them were minors at the time, and since I have no way to obtain publication releases, I will not provide any details that could lead to identifying any person who had contributed to this project.

Prologue: The query that led to the project:

A friend came to me in late 1970 with a technical question: Can five tape recorders be synchronized?

I began to think on the complexity of this question, including the following facts:

  1. They wanted sound effects to come from at least 5 different directions in the auditorium.
  2. They were talking about the Wollensak mono tape recorders that most schools had in the 1960s.
  3. Those Wollensak tape recorders had no synchronization capabilities.
  4. I had been experimenting with the Hafler (Dynaco) quadraphonic system earlier in the year.
  5. Several ideas came to mind:

    - Use one tape recorder and switch among several speakers. This would require switch position cues for each sound.
    - Switching speakers also required as many speakers as the number of directions the sounds need to come from.
    - Turn on a separate tape recorder for each wanted sound direction.
    - Use a quadraphonic system and recording.

We decided to use the Hafler quadraphonic system using a stereo tape recorder, a stereo amplifier, four speakers, and lots of speaker wire.


The Auditorium

Hafler decoder

Hafler Speaker Matrix

The Auditorium we Used

This was a typical high-school auditorium except that it was designed with safety in mind.

Building the Quadraphonic Speaker Setup

This is how the quadraphonic speaker layout was assembled in the auditorium:

my encoder

Encoding System

my encoder

Monitor Speakers

Building the Encoding Setup

The encoding equipment consisted largely of equipment I already had, plus borrowed tape equipment:

- Panpots are much easier to use.

- My concept of using a mixer to encode was born.

The Test Tape

I made a test tape containing the following tracks:

* This quarter-turn rotation was accomplished by:
- Putting the original left channel in the front (in phase in both channels) and
- Putting the original right channel in the back (reversing phase of left channel feed).
- This put material that on the record is centered between the speakers on the right.

I used this tape to set up and adjust the settings on the amplifier.

The Play

Ondine is a play written in 1938 by Jean Giraudoux about Hans and Ondine. Hans, a knight, meets, falls in love with, and marries Ondine, a water-sprite disobeying her purpose. The marriage has tragic consequences.

pan plot

Encoding pan plot

Encoding the Sound Effects

I was given a half-track mono tape containing the sounds they wanted to use in the play.

I first read the parts of the script having the sounds and voices and a list of the desires the director had for where to place the sounds. He wanted some of the voices to intentionally come from the wrong directions (different from the location of the visible entity) for effect.

I made my first ever quadraphonic pan plot that day. I still use these pan plots for surround recordings today. But I no longer put diamonds or other shapes showing speaker locations in them. I usually use a circle to show the entire sound field.

When I positioned the King of the Sea (KS), I was thinking of the out-of-phase "hole" the theorists said existed there. I wanted the position to be indistinct. But actually trying this positioning with the equipment showed that the "hole" was not the problem the experts claimed. The image was stable where I put it.

I still have those pan plots. But I wrote other things about the play on the backs of the pages the plots were on and the ink bled through. So it was easier to make a new one than to try to separate the wanted material from the unwanted.

Here is how each sound was encoded:

SoundsIdentityEncodingVisible Item
O1 V1Ondine's 1st Sisterleft side (straight left)stage left
O2 V2Ondine's 2nd Sistercenter backcenter stage
O3 V3Ondine's 3rd Sisterright side (straight right)stage right
HA head seen in a windowslightly right of center stagecenter stage
NA naiad (spirit) seen in a windowslightly left of center stagecenter stage
KSThe King of the Sea (known as The Old One)right backcenter stage
SEVarious onstage sound effects (e.g. falling armor)center stagecenter stage
GOA gong struck by a servantcenter stagecenter stage
T1L Thunder recorded on two tracks for an overhead rolling effect
T1L is a few seconds ahead of identical T1G
left side Lighting cue onstage
T1G right side
T2L Thunder recorded on two tracks for an overhead rolling effect
T2L is a few seconds ahead of identical T2G
T2A a different thunder track starting one second before the end of T2G
center back Lighting cue onstage
T2G center front
T2A left front
T3L Thunder taken from a stereo sound effect record
T3L and T3R is a repanned stereo recording
right front Lighting cue onstage
T3R left back

The thunder tracks were made by recording the L (leading) track on one track of the half-track recorder and the G (lagging) track on the other track on the half-track. Then these tracks were simultaneously played through the encoder set to the pan positions in the table and recorded on the quarter-track recorder.

On the original tape, T2A was intended to be T3L, but that changed (below).

After the tape was completed, the sound man spliced leader tape in between the sound effects so the tape operator knew when to stop the tape after each effect.

The Dress Rehearsal

One glitch developed during the dress rehearsal. T2L and T2A (originally T3L) were left as one piece of tape because the sound man could not find the cut point.
The fade out of T2G led into T2A with no clear break.

I created a new strip of tape with the T3L and T3R tracks from a stereo record I have. The sound man then spliced it in with more leader tape.

The Performances

The performances worked quite well. The sound effects were quite effective. Only one glitch occurred with the sound: The tape operator accidentally hit fast-forward instead of play and skipped one sound effect for one performance.

After the Play

I had wanted to make a copy of the tape after the play was over for evidence that I had done this, but I was told that, because the voices of minor students were on the tape, there would be a legal problem with me keeping copies of any of the materials. So I have no record (other than my pan plots and the play program with my name in it) to show that it ever happened.

I can't even show the auditorium to anyone anymore. The building was torn down and a computer center for the university was built there.

This play took place in early 1971. I believe it was the very first use of matrix quadraphonics in a live theater presentation.