Possibly relevant, & certainly interesting... www.righto.com/2016/02/555-timer-teardown-inside-worlds-most.html On 2/23/16, Jesse McCreadie wrote: > Hi Lindy, > > I build Modular synthesizers for a living. > The 555 square wave certainly can be used for subtractive synthesis. > If you're looking for tonal stuff the standard is 1V/Oct and that's where > the problem with the 555 comes in . > Difficult to scale the control for 1V/Oct. > Great for Lunetta stuff and noisemakers! > > There's a bunch of great SynthDIY sites and forums to help get an overvie= w > of different architectures of VCOs and VCFs. > Haha i guess it depends what your end use is really ;) > If you're shooting for a Moog-Like synth 555 is the hard road to go. > if you're less interested in traditionally tonal music and just need a > simple oscillator 555 is great. > MFOS makes a Weird Sound Generator using 40106 as a fistful of astable > multivibrators. > > On Tue, Feb 23, 2016 at 4:15 PM, IVP wrote: > >> > Is the square wave that comes out of a 555 something that can be >> > used, then filtered to make different sounds? >> >> Absolutely. Even varying the duty cycle during a note can sound >> interesting. >> >> You can also get a triangle wave from a 555, which is less harsh >> on the ears than a square wave. A few components can convert >> the triangle to a sine wave. The Control Voltage pin (5) can be used >> as a modulating input, for example to make the 555 the basis of a >> voltage-controlled filter. 4016/4066 switches are put in series with >> resistors in a typical audio filter and the 555's duty cycle is altered >> (via CV) to change the tone. Which could be anything from a simple >> bass-treble control to a sweeping wah sound. The audio source >> can be another 555 >> >> With a handful of 555s you could make a small basic old school >> modular synth - VCO, VCF, VCA, LFO etc >> >> I've seen a circuit which used the 555 as (I think) a pulse-position >> modulator as an audio amplifier. I remember the author said it >> wasn't fantastically good but demonstrated a principle >> >> Have a Google for 555 Cookbook, plenty of odd circuits around >> >> Joe >> >> >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2016.0.7442 / Virus Database: 4537/11683 - Release Date: >> 02/23/16 >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .