About PWM and frequency range

[soren]

Hi guys.

I have a Z8 Encore evaluation board, and I would like to use it to make some digital effects. Since I am completely new at this, some questions have arised:

-What is the frequency range of an electric guitar? (I'm kind of embarrased that I don't know this... Please educate me!)
The ADC on the chip can sample a 10-bit value every 256 clock cycles (72 kHz, if my calculations are correct...) I suppose that this is sufficient?

-Will a PWM output and a lowpass filter work for reconstruction? The chip runs at 18.432 MHz, with 16 bit timers for generating PWM output. Again, I'm worried about resolution, frequency range, etc... At what minimum frequency should I drive the PWM? How many bits of resolution do I need to make it sound like music?

I guess it all adds up to this: Is it doable?

Thanks for reading, any help is appreciated!

[idlefaction]

Hi,

I don't know the Z8 Encore so I'm not sure on the specifics.

Most people agree that CD quality, or 44kHz, is a pretty good sounding sample rate.  You could go higher if you wanted, the higher the better, just make sure the chip doesn't have upper limits on how fast you should use the ADC.

PWM and a LPF works great as a DAC for audio.  (TLA's anyone?)  The minimum frequency you should drive the PWM at is probably around 40kHz, or twice the highest frequency you want to reconstruct.  Use as high as you can - the reconstruction filter will reduce it more that way.

Sounds doable  :-)