GAIA Exploring Sound (PDF) - Roland Corporation Australia

So now you can choose which method you prefer. Hardware or
software. Either way you can turn on a delay signal.
What is Delay?
We’ve all seen movies where someone might yell out to the
mountains. They say; “hello,” and some time later they hear their
voice return; “hello.” The sound might not be as clear, but is very
definitely an echo of their voice.
This time-delay occurs because sound travels at a finite speed. It
takes some time for the sound of the voice to reach the first
mountain, and then the same amount of time to bounce back.
This is what we refer to as Delay in the GAIA. You play a note, and
after a predetermined time-delay you will hear that note played
again.
So, back in the 1980s, how was that effect achieved?
Actually, prior to that, musicians would use what they called a
tape delay, like the very famous Roland RE-201.
Figure 10.4 Roland RE-201
This device really was an elaborate tape recorder. It had one
record head, and several playback heads. A loop of magnetic
tape would pass the record head, receiving the signal. It would
then travel on to the first playback head.
Depending upon how fast the tape was moving this first playback
head would replay the signal after a small time-delay. The result
was much the same as the guy in the mountains.
However, then the tape would pass more playback heads, each
with a slightly greater delay caused by the tape passing them in
succession. As a result the Delay would be repeated. A sort of;
“hello,” “hello,” hello,” “hello” effect.
Times Change
As time moved on it became obvious that the Tape Delay concept
wasn’t going to last. The tapes would wear out, degrading the
sound. Being a mechanical device the parts would need constant
maintenance.
So a better solution was needed, preferably purely electronic.
One of the earliest solutions was to take advantage of what was
called a “bucket brigade” device.
Imagine a fireman trying to put out a fire. Let’s say that his water
outlet is 15 meters from the blaze. Of course, he could just fill the
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