[sdiy] Q: oscillator bank

[Grant Richter]

A Fatman works very well. The exponential DAC seems to be a great
improvement over the exponential transistors.

> From: Scott Gravenhorst <music.maker at gte.net>
> Reply-To: music.maker at gte.net
> Date: Mon, 15 Nov 2004 07:07:12 -0700
> To: synth-diy at dropmix.xs4all.nl
> Subject: Re: [sdiy] Q: oscillator bank
> 
> A partial example of this is the PAiA FatMan synth.  It uses 2 VCOs both
> driven by the same linear control voltage.  All that is needed is to create
> an expo converter that makes a voltage from the normal current output to
> drive the linear CV input to the VCOs.  Full details at http://www.paia.com
> 
> Grant Richter <grichter at asapnet.net> wrote:
>> This is exactly how the EML-101 was done. There are two uA726s, one for the
>> VCOs and on for the filter. But everything is linear voltage responding.
>> 
>> It works, a bit fussy though.
>> 
>>>> My thoughts on this:
>>>> - sum the various control voltages: keyboard key, plus modulation, plus
>>>> pitch-bend
>>>> - apply to the exponential converter
>>>> - use the converted Hz/V value to drive several oscillators
>>>> - each oscillator has octave switching via a resistive divider
>>>> - each oscillator (but one) has scaling to allow relative tuning +/-
>>>> some interval
>>>> 
>> 
> 
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