Ensemble Circuit Configuration Questions

[KA4HJH]

>Any additions/corrections to the above list most welcome.

The Marshall Time Modulator isn't an ensemble effect per se but this
article in issue 1:10 of Device is pretty interesting so I scanned and
OCRed a portion:

Pete: How do you format the delay lines in the Time Modulator?

Steven St. Croix: There are 8 delay lines total, that are grouped together
into 2 main delay lines; each main delay comprises 4 delay sub-lines. A
signal feeds four parallel delay lines, and those 4 lines are divided into
two families. The two lines of each family are clocked out of phase; they
see the same audio input, and the outputs are positively summed. What that
does is basically double the sample frequency, in fact, your Nyquist
frequencyŠcan almost reach the clock frequency. In most charge transfer
systems you get two copies of the sample to fill up the "gaps" caused by
clocking, which means the data is not as valid as you would like it to be.
With the Time Modulator clocking scheme, every piece of data is valid; any
gaps are filled with the real signal, not a copy of something that happened
previously. This way we can clock at lower frequencies, but you have the
advantages of clocking at higher frequencies ... you need fewer transfers,
thus reducing distortion, noise, and other problems.

Now remember that we still have a second family of delay lines. This family
is clocked the same way as the first family (parallel multiplex mode), but
the audio signal going through one of the families is inverted.
Essentially, you're drriving the two families differentially; and when you
add them together, you cancel out even harmonic distortion. So, you end up
with. a long, clean delay without having to go through a great number of
transfer stages. With this system you can clock at 100 KHz and keep a
bandwidth of 90 KHzŠ

Some specs:
s/n 85-95dB
sweep ratio 72:1
Delay time 400mS

Pretty impressive for twenty years ago. I wouldn't mind to have one.

Terry Bowman, KA4HJH
"The Mac Doctor"

ICQ: 45652354