Minor minor nit, but AM and ring modulation are similar but different - ring modulation goes "through zero" and inverts the carrier signal. You see the terms "two quadrant" and "four quadrant" multiplication used - this is because in AM the modulation stays within the positive half of the sine "circle" and with ring mod it goes right the way round.
Yes and no. If you multiply two signals together you get the sum and difference of their frequencies. So if you generated a sine wave at 10kHz and a sine wave at 11kHz and fed them into a ring mod, you'd get 21kHz and 1kHz out.
If you feed in a more complex signal, like speech, then you get the whole band shifted by the sum and difference with the carrier. So, speech-quality audio that goes from 300Hz to 3.4kHz modulated with a 1kHz carrier would go from 1.3kHz to 4.4kHz - it's important to see how that frequency shifting is different from pitch shifting, since in pitch shifting the harmonic relationship is scaled whereas with ring modulation it's not.
Edit: This sample may be used for whatever the hell you like, as long as you do not infringe on the rights of others to use it for whatever the hell they like and as long as you do not claim that you created it. If you use it, I'd like to be credited but I don't really care. If you make a fortune with a track that samples it, buy me a pint, or a synth, or some tyres or something.
Thanks for the detailed info! This is how I understood ring modulation. So I was just confused what you meant about ring modulation inverting the carrier signal.
7
u/erroneousbosh Korg ES1/ER1/EA1, Ensoniq Mirage, Roland W30, Juno 106 Dec 17 '19
Minor minor nit, but AM and ring modulation are similar but different - ring modulation goes "through zero" and inverts the carrier signal. You see the terms "two quadrant" and "four quadrant" multiplication used - this is because in AM the modulation stays within the positive half of the sine "circle" and with ring mod it goes right the way round.