I agree with nickrose that the difference in analog circuitry and automated input gain control loads the guitar input slightly differently with the H9 sounding a tiny bit more "sterile" than the Factor pedals, a just barely audible difference with some effects, with guitar plugged directly into pedal. With an active buffer or driver between guitar and pedal – high quality compressor, preamp pedal, or buffered output tuner – the difference is imperceptible to my ears. The manually switchable input and output levels of the Factor pedals are a definite plus for matching gain levels with other devices, particularly the differing levels encountered in guitar amp effects loops.
