How do you LP wo/caps?

[Tim Ressel]

Sounds like you harnessed the power of stray capacitance, and used it to do Good
and not Evil ... which is its normal role.

Tim Ressel--Compliance Engineer
Hewlett-Packard
Verifone Division
3755 Atherton Rd.
Rocklin, Cal
916-630-2541  
timothy_ressel at hp.com



-----Original Message-----
From: tomg [mailto:efm3 at mediaone.net]
Sent: Thursday, July 27, 2000 6:14 PM
To: synth-diy at node12b53.a2000.nl
Cc: efm at xavax.com
Subject: How do you LP wo/caps?



I am not sure what I have done! But on my bench right now
is a 2 stage (pole?) LP filter that sounds much better than 
most of the 2 or 4P LP group that has no caps! Actually
it doesn't have much of anything.

1 - dual pnp
1 - dual ota
2 - pots
16 - resistors

The upper range is especially clear and transparent almost
sparkling but it roars down into to lower range. Notably 
when oscillating the sine is very symmetrical and uniform. Being 
stable to less than 1Hz. It really sounds terrific...No 
kidding!

It's done with multiple feedback paths. Without me giving 
too much away, has anybody ever seen anything like this 
before?

Tom