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Bob Masta[_2_] Bob Masta[_2_] is offline
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Default "Random" Circuit Needed.

On Sun, 26 Apr 2015 09:32:00 -0400, rickman


Really? There are many ways of generating PRS. There are trade-offs
with each one. If you don't need the speed or small size an LFSR has
disadvantages compared to many others.

I hesitate to get into this, err, "discussion", but in
software at least, an LFSR has one nifty advantage over the
simpler and more-common linear congruential approach: You
can run it backwards!

Why would you want to do this? Well, one fun application is
to run two identical LFSRs in parallel and sum their
outputs to produce comb-filtered noise, where the offset
between the two LFSR sequences controls the the periodicity.
Then you can modulate the offset of one stream to slowly
sweep ahead and behind the other to get a "flanger" effect.

See "Comb Filtering and 'Flanger' Effects" at

Best regards,

Bob Masta

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