[sdiy]Re: [sdiy] VCO IC's usage inquiry

[rdrake]

most 555 osc. circuits produce square-waves only, have a limited freq. range, and a linear response... other waveforms and log response are generally much more useful for musical applications.  (thomas henry published a book with solutions to those limitations, but it is no longer available)...  i still use 'em for clocks occasionaly, but hardly ever as sound sources... 

i just finished a custom noizebox w/ 2 of René Schmitz's osc. based on the cmos 4069... 

http://www.uni-bonn.de/~uzs159/vco4069.html

more parts than a basic 555 circuit, but still pretty dead-simple... log response, both saw and pulse out, even PWM.  and he even provides a perfboard layout.  add variable cross-modulation and a cmos "ring" modulator, and its a pretty glorious din.  recommended.

bbob



>Logan Mitchell Sr wrote:
>
>11/09/2005
>I am constructing my own synthesizer and am using
>the 555 IC Timer chip for
>my VCO's. Is it better to use the 555 or something
>like the 741 or other op
>amps for a VCO ?
>
>Logan Mitchell Sr
>Baltimore MD USA
>
>