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Subject: Re: [tubesynthdiy] Did anyone built the" noise source" aka vacuum tube random noise generator...?

From: =?ISO-8859-1?Q?G=F6ran_Sandstr=F6m?= <vektor@...>
Date: 2007-06-01

One obiously awesome thing to do would be to make the magnet rotate around the tube, closely... 
Having a motor and being able to control direction and speed w. gate and cv respectivly would probably be quite interesting...
Ken, what do you think about this?

Btw i have a drawing for how to do it in my head, looks rather old school sci-fi-ish...

Göran Sandström aka Veqtor
CEO, Designer and Manager
OXO-Unlimited Recordings
Tel: +46 (0)735021433
www.myspace.com/Veqtor




1 jun 2007 kl. 09.03 skrev sasami@...:

>I'm building this one that you can find here:
>http://www.cgs.synth.net/tube/noise.html
>And i am thinking about adding pots, one on 2d21 pin6, and/or another
>one on the 12ax7 pin2, did some one tryed this?is it a waste of time
>and money? does anybody have some ideas excepted vactrol on pin7...
>thank you

Waste of time and money. I expect all you would achieve is a volume control
in both cases, with the addend chance of cooking the 2D21.
Perhaps a pot between a positive voltage and earth connected to pin 5 of the
2D21 may have an effect, though what I don't know. Perhaps a 1M pot in
series with a 1 1M resistor to the power rail, amd make sure you use a pot
rated for the voltage!
Another thing that may be worth experimenting with would be to replace or
augment the fixed magnet with an electomagnet, as moving the magnet does
have a noticable effect.

Ken
__________________________________________________________
Ken Stone sasami@hotkey.net.au
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