[jakedanger]

What exactly is going on when you use frequncy modulation by a modulating oscillator to control the sound produced by a carrier oscillator (I'm using a Reason Subtractor synthesizer)? If I keep the modulating oscillator on, turn on frequency modulation, turn the Mix knob to the left so only the carrier oscillator can be heard, then of course the modulating oscillator affects the timbre of the sound put out by the carrier osillator, even though the modulating oscillator itself cannot be heard. But why is it that when I then adjust the pitch of the modulating oscillator, the pitch of the output audio (put out only by carrier oscillator) changes correspondingly? I had thought that frequency modulation did not affect pitch.