I'm unable to find the info about how to treat a guitar signal. Should i see it as a sine wave or a much complex sawtooth or triangular wave? as i don't have my hands on an oscilloscope i cant see the actual waveform. Plz Help :)
Don't worry so much about what the signal looks like. It will be a combination of sine waves of related and unrelated frequencies.
Of more importance are:
- Frequency range (you want to accept roughly 200Hz to 12kHz and if the pedal produces higher harmonics eg a distortion then you may want to output up to 20kHz)
- Signal levels (up to about 2 Volts should be expected, so make sure your circuit can accept more than this so it doesn't cause unwanted clipping)
- Impedance (high input impedance and low output impedance)
I think you have to consider the signal as rich in harmonics as possible, since provided the fact signal is not a pure sine wave, it could be represented as a set of infinite harmonics. Of course is not possible to have an infinite bandwith with anything, but as for any other instrument, the large the bandwidth is, the better the result.