ASM-1 vco range

[Magnus Danielson]

From: jimh54<jimh54 at tx.freei.net>
Subject: ASM-1 vco range
Date: Thu, 8 Jun 2000 07:04:34 -0500 (CDT)

Jim,

> Anyone know how to decrease the range of the VCO's on an 
> ASM-1? Mine has an extremely wide range. Haven't measured 
> the frequency range but the knob only turns about 1/3  
> before the frequency is above hearing range. I want to lower 
> the range on the pot so it only operates in the audio range.
> same is true on both VCO's. I used MAT-02 matched pairs and 
> all precision 1% resistors.

The only thing you should need to do (and also the only thing you
SHOULD do) is to change the sensitivity of the VCO for you knob
tweaking. This you can do by simply increasing the resistor from the
pot tapper into the CV summing amp. Double it and see if that does the
trick for you.

This will not in any way change the actual range of the VCO and there
is no reason for it, it will just make you knob twisting less extreme.

I've clocked my ASM-1 for a range of over 20 octaves but the tracking
where not particularly great in the top extreme. In this sence the
ASM-1 VCO is quite extreme so you go from below earthquake to having
the dogs going totally bonkers. Hmm... time to revisit that
measurement exercise....

Cheers,
Magnus