Osamu Hoshuyama discret vca

rubendelacosta · Joined: Dec 25, 2005 Posts: 151 Location: lisbon

hi!
anyone have build this vca circuit?
http://www5b.biglobe.ne.jp/~houshu/synth/Vca0302.gif

i have some questions about it.

can it handle negative voltages?

i have no idea what values i should start experimenting, since no components are labeled.
can anyone point me some staring component values to experiment with this circuit?

thanks,
ruben

andrewF · Posted: Thu Jul 22, 2010 6:28 pm Post subject:

I think it is a core circuit, a starting point.
have a look at Ken Stones CGS64 VCA
and Rene's VCA3:
Posted Image, might have been reduced in size. Click Image to view fullscreen.

Posted Image, might have been reduced in size. Click Image to view fullscreen.

emdot_ambient · Joined: Nov 22, 2009 Posts: 669 Location: Frederick, MD

Where can one find supermatched pairs nowadays? The CGS VCA can use a variety of them--they list 2SC3381, 2SC1583, MAT02, LM394 & SSM2210 as possibilities--bu so far I can't find any for less than $10, including shipping. Crying or Very sad

frijitz · Posted: Fri Jul 23, 2010 12:52 pm Post subject:

emdot_ambient · Joined: Nov 22, 2009 Posts: 669 Location: Frederick, MD

Hmm....Seems like maybe I did get some from Futurlec at one point. Need to check my stock, maybe I'll be luck and find I had ordered a couple dozen of them.