>First, you can simulate overtones by where you strike a guitar.
If you know the make of the guitar and the strings and where it was picked each time and the location of each of the tone and volume knobs and the position of the pickup switches.
>Tube amps do some really funky mixing, which can exasperate FFTs by giving weird/wrong results.
If you know the make of the guitar and the strings and where it was picked each time and the location of each of the tone and volume knobs and the position of the pickup switches.
>Tube amps do some really funky mixing, which can exasperate FFTs by giving weird/wrong results.
>unknown non-linear effects...distortion