MOTM

...Paul, any plans in the far future for an MOTM Frequency Shifter? I know
J\ufffdrgen Haible has been working on one; I wonder how that's going/went.

I never used a frequency shifter, but ever since I read an Interview with
Wendy Carlos 15 years ago where she said that she used it to get her
classic, shimmery "Christmassy Sound," I've been curious. I've tried getting
a series of HP filters to track a keyboard for a really steep-sloped filter
to try to imitate one by just grabbing the upper sidebands of a Ring
Modulator's output, but that's so hack, and I never got it to work properly.

I understand there's a hell of a lot of circuitry involved in a true FS.

In a message dated 2/9/2000 1:47:45 PM, Ken.Tkacs@... writes:

> I've tried getting
>a series of HP filters to track a keyboard for a really steep-sloped filter
>to try to imitate one by just grabbing the upper sidebands of a Ring
>Modulator's output, but that's so hack, and I never got it to work properly.

I'm sure Bradley, Crow, Hugo (and more?) have a much better understanding of 
frequency shifters than I do. I think your general concept is good, but I 
think you will lose the pitch relationships by this method -- you know, the 
sum and difference thing as opposed to the doubling relationship of octaves. 
Does this make sense?

JB

In a message dated 00-02-09 15:47:48 EST, you write:

<< I understand there's a hell of a lot of circuitry involved in a true FS. >>



ken,
well, 2 balanced mod circuits (or is it one, i can`t recall at the moment for 
sure, oops, :^(  ), some 90 degree phase shift networks, assorted summers and 
a carrier oscillator. i recall that electronotes had one designed quite a few 
years ago. using that as a starting point should be feasible. especially with 
the analog devices ic`s for ring modulators. much better than 595`s or simple 
ota circuits.
best,
dave