[sdiy] Additive Synthesis questions

[Oren Leavitt]

Aaron Lanterman wrote:
> On Apr 11, 2010, at 1:25 AM, Ian Smith wrote:
> 
> 
>>What sort of incandescent bulb do you use for this? something like the tiny little ones you can get at Radio Shack?
> 
> 
> I can't remember what/where now but there is an app note on sine wave generation that specifies a particular kind of bulb.
> 
> - Aaron


This circuit using using a FET AGC approach has worked well for me:
http://www.analogcreations.com/images/wein_osc.jpg

For incandescent lamps, a 28V 40-60ma (GE 1829 et al) lamp works well 
with a 220 ohm resistor in the feedback loop around the op-amp.
Nice low-distortion osc that is slightly microphonic when you bump it :-).

- Oren