[sdiy] more pitch shifter thoughts

[Grant Richter]

With all due respect to the fine engineers here.

One mans defect is another mans Wogglebug.

I would have to say the purpose of experimental devices is to experiment.

I have sometimes succeeded with designs because I was unaware that they were
impossible. Or you are just as likely to discover something more interesting
than you were trying to do to begin with, if you keep an open mind (ear?).

One creative technique is to sit down with a breadboard and tinker with a
thing until something interesting happens (like Serge Tcherepnin), instead
of the more academic method of doing an exhaustive Spice simulation and
simulating the fun out of it.

Obviously I am refering to amusing noise makers and not medical equipment or
man rated aeronautics.

> From: Scott Gravenhorst <music.maker at gte.net>
> Reply-To: music.maker at gte.net
> Date: Mon, 10 Jan 2005 10:00:48 -0700
> To: synth-diy at dropmix.xs4all.nl
> Subject: Re: [sdiy] more pitch shifter thoughts
> 
> Grant Richter <grichter at asapnet.net> wrote:
>> You can build one with just a top octave chip and a CD4046. The TOC just
>> need a high frequency clock phase locked to a reference VCO square wave. A
>> switch can select the high or low C from the TOC and give and octave above
>> or an octave below the reference VCO. (IIRC with a 50240)
> 
> Being a 4046 PLL kind of guy, I have wondered about stability and tracking
> when doing this.  I have a PLL module that uses a divide by 12 counter in
> the loop and it works just fine.  But the MK50240 has a range from divide
> by 239 to divide by 478.
> 
> What kind of problems, if any, will there be with such large counters?
> 
> I would think that proper VCO capacitor selection is important.
> 
> Over/undershoot? 
> 
> Does a large counter affect lag very much?
> 
> My own circuit has adjustable damping for the loop filter and allows me to
> adjust it so that frequency changes are so immediate that I do not hear any
> over/undershoot or lag.  But then, my PLL has only a divide by 12 counter
> in the loop.
> 
> 
>>> From: Steve Ridley <spr at spridley.freeserve.co.uk>
>>> Reply-To: spr at spridley.freeserve.co.uk
>>> Date: Mon, 10 Jan 2005 18:32:05 +0100 (CET)
>>> To: synth-diy at dropmix.xs4all.nl
>>> Subject: Re: Re: [sdiy] more pitch shifter thoughts
>>> 
>>> 
>>>>> EML PolyBox
>>> 
>>>> Any idea how they did it?
>>> 
>>> Schematics are available at the yahoo EMLSynth group.
>>> 
>>> 
>>> Steve
>>> 
>>> 
>>> 
>>> 
>>> -- 
>>> 
>>> Whatever you Wanadoo:
>>> http://www.wanadoo.co.uk/time/
>>> 
>>> This email has been checked for most known viruses - find out more at:
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>> 
> 
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> -- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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