lokki:
but i want that sound! it has to be sample rate reduced. i don't want a clean nice signal.
i would not use the schematics on the intstructable site. have not even looked at it. i am able to do my own preamp and filtering at input stage, bias etc. i have built many pedals.i just have never worked with arduino and this ADCH mode for the analog input.
so, back to my question. can you adjust the sample rate dynamically?
ok, that is a start. but would that not mean that i can only get half the sample rate or a third etc? processing every n-th input sample only? i already tried this approach (just outputting every n-th sample) and it works, but control range is obviously very limited. or can you elaborate a little more? how would you decimate the sample rate smoothly? as i said lowpass filtering is not what i am after, since the signal should alias on lower sample rates... i also tried some software versions that use sample and hold to achieve kind of sample rate reduced sound, but it sounds not the same.
Decimation is the name of the technique, its not a secret.
Perhaps you should say what you are trying to do, "control range" doesn't make any sense to
me in the context of signal processing.