Moog Music Forum

I have wondered for a while how ring modulation creates an octave up. I also wondered what would happen if I plugged a microphone into the 'carrier in.'

As for the latter, the result is vocoder . . .-ish.

To turn the 101 into a Moog octave-up pedal, split the guitar signal into two. Run one half into the normal input, run the other half into the carrier-in.


I do not know if this is common information or not. I share this in hopes that others know things or little tricks that they might also share - especially for guitarists. (This does not seem to happen much on this fooger BB.)

Anyway. Try this and let me know what else you come up with.

kb wrote: To turn the 101 into a Moog octave-up pedal, split the guitar signal into two. Run one half into the normal input, run the other half into the carrier-in.

Tried this today. Very cool, sounds exactly like an octave pedal. One problem is that the sound goes down in volume compared to the bypass volume. But whatever, still a cool trick, Thanks for the tip.

boost the signal going into the carrier in with an overdrive or whatever else you can think of.

The reason it sounds like an octave up pedal is because when you configue it the way you described is because, when configured like that, thats exactly what it is. A ring mod works by combining two signals (the input and the carrier) and outputing the sums and differences of the frequencies of the two signals. The resulting effect goes something like this: say the input is at 500Hz and the carrier is at 100Hz, the RM will output two distinct signals: 400Hz and 600Hz.

HOWEVER, if the carrier and the input are the SAME signal (like the setup above), it goes a little sumpthin' like this: say the input and carrier are the SAME SIGNAL at 500HZ, the output of the RM would be 1000Hz and 0HZ. In audio, doubling the frequency is the same as shifting an OCTAVE UP (e.g. middle C is approx 262Hz, an octave above middle C is approx 2 X 262 = 524Hz). Understand?

Good idea, by the way! I hadn't thought of that!

Since you have disconnected the LFO (as you are using an external carrier), why don't you send the LFO out to Mix jack, and get a modulating octave effect?

how could you make it an octave lower?
is there anyway of isolating the two signals you get out of the 102?
say you ring modulated your voice at 300hz with a signal from a synthesizer at 100hz to get signals at 400hz and 200hz, what if you only wanted to hear one of those signals?

godzilla wrote:how could you make it an octave lower?

You can't because the difference of the same signal will always be 0Hz. To pitch a signal an octave down, you would have to DIVIDE the frequency in half.

godzilla wrote: is there anyway of isolating the two signals you get out of the 102?

Not with the MF-102, I dont know of any ring mod that can do this. That would be cool, though. Anyone know of any ring mods that can?