Walsh function website update

[jorgen.bergfors at idg.se]

Isn't this just adding square waves, like they used to do with electronic 
organs back in the 70s? Wersi did this, to get a sawtooth from a top octave and 
octave divider tone generator. 
I modified the Elektor electronic piano, which used square waves, by ORing with 
an octave higher. That created a 25% duty cycle pulse, which sounded better. I 
even ORed the higher octave vith a constant 1 or 0 so I could switch between 
the waveforms. This was around 1980.

/Jorgen





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Subject: Re[2]: Walsh function website update 

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Subject: Re: Walsh function website update
To: smoking silicon <synth-diy at mailhost.bpa.nl>
Date: Fri, 14 Aug 1998 15:48:26 -0400 (EDT)
From: Eli Brandt <eli at gs160.sp.cs.cmu.edu>
In-Reply-To: <5d3158d0 at camcon.co.uk> from "Neil Johnson" at Aug 13, 98
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     Mmm, modulating the Rademacher functions could be interesting.
     
     Especially if you modulate only one Rademacher function, since if 
you 
     use the generator I've sketched (using ExOR gates) only a subset 
of 
     all the Walsh functions will be modified, eg:
     
     WAL(2)  = WAL(1)WAL(3)
     WAL(4)  = WAL(7)WAL(3)
     WAL(11) = WAL(15)WAL(4) <= since WAL(4) = WAL(7)WAL(3)
     WAL(12) = WAL(15)WAL(3)
     
     ... etc.
     
     I'd be interested to hear about your conclusions.
     
     Neil
     
     +======================================================+
     |     Neil Johnson  BEng(Hons) MSc CEng MIEE MIEEE     |
     |         http://members.xoom.com/Neil_Johnson         |
     |       "I speak for myself, not for my employer"      |
     +======================================================+
     


______________________________ Reply Separator
_________________________________
Subject: Re: Walsh function website update
Author:  eli+ at cs.cmu.edu at Internet-PO
Date:    14/08/98 15:48


Neil Johnson wrote:
>      http://members.xoom.com/Neil_Johnson/walsh.html
     
Thanks, interesting stuff.  I want to code something up and see what 
happens when you detune or PWM the Rademacher functions...
     
By the way, are there special tricks that Walsh functions do, compared 
to using pulse waves or something?
     
-- 
     Eli Brandt  |  eli+ at cs.cmu.edu  |  http://www.cs.cmu.edu/~eli/