Vintage Synth Explorer Forums

Hello Everyone,

I started studying ring modulation, and was able to come up with some fairly musical observations. Thought I'd share with the bruthas and sistas out there on the VSE realm.

Here's a link to my blog

Hello again Everyone,
up late again trying to save the universe! I've got a special treat for you all tonight. Ring Modulation. As a few of you have heard, I now own a Moog MF-102. I've been trying to research how players use this pedal, or others that function in the same schematic. To be honest, it's been rather rough, trenching through the internet looking for settings, tips, tricks, anything and coming up with enough of the picture that I figured out how to fill my gaps.

So this all starts off with basic addition and subtraction. Whatever frequency (or pitch) you input will be added to and subtracted from the carrier frequency (the one you set with the Freq. knob on the bottom left), which gives you two new frequencies. Now, using the mix knob on the top right you can blend your original signal with the new one, combining to three pitches coming out. If I playA4 @ 440 and set the frequency knob to C6 @ 1040 we hear F#6 @ 1480 and a rather sharp D5 @ 600, which could be interrupted as a D major triad with it's fifth (A) in the bass. Where it gets crazy is when you play notes other than A, the two "new frequencies are going to move because of the moving relationship of your source and the frequency knob.

Throughout my searches in forums I found it interesting that just about everyone referred to the Ring Modulator as it's own instrument being triggered by yours, and that thinking about it like this yields more musical results. There are a few things to take into account when playing with an instrument like this:

It is a numbers game. If you tune your frequency knob to close to a perfect unison, it could sound rather hollow, because x-x=0, so some distance between the two is a good idea. Additionally, because of the equations nature, it doesn't take into account that the amount of Hz between pitches increases as you move up through the spectrum. What this can yield is a much more stable set tones, that act more like drones, moving in 2nds instead of 5ths and 6ths. Another common production is that your descending line will have more motion, because of the nature of the spectrum.

Just for a clear example, moving up 180 Hz from 914 yields what we hear as a Major 2nd (Bb5 to C6), where as moving down 180 Hz from 653 yields what we hear as a Major 3rd (E5 to C5)

Another thing to keep in mind, you will find negative results in the subtraction side of the algorithm. What happens here is that it will fall further and further into the negative side of the spectrum. What the pedal, and additionally our ears translate this as, is it's inverse. If you cross 0, you will hear two rising pitches. If I understand correctly, it will happen when your source is playing a higher frequency than the frequency knob is set to.

So I just finished using Excel to create a pitch to Hz spreadsheet and a series of equations displaying the output pitches of two major scales. They are listed below for you to look at, along with the frequency chart. I also posted a video I found helpful on youtube. It's a 3 part series, and it's heady, but I found it helpful.

This is going to be a rather extensive research, so keep a look out for more.

Enjoy,
CJF

I find I get more productive results from ring mods when I stop worrying about key and just play rhythmically.
Most percussion and drums sets are not "in key" but still function fine in a musical context.
Playing with an ear for texture and rhythm while moving your fingers around enough to keep it interesting seems to work.
As far as the unison, I sometimes dial in the Ring Mod to be a 5th from whichever note is held the longest in a phrase. That way the rest of the notes sound jarring and out of tune, then the held note, usually the last, sounds EXTRA in tune.

In my experience, the addition of an expression pedal really enhances the functionality of the ring mod.

My favourite trick , reminiscent of the CS-80 ring mod implementation, Is to split the CV out from the pedal into 2 separate leads, send one to the Mix control with the initial level set to around 10% just so the ring mod bleeds through whilst the pedal is neutralised. Send the other CV out to the Carrier Frequency with the initial level being set to a nice fluent tremolo.

Set the expression range to maximum and you can get some very interesting, musical results in-between non-modulated playing. Vangelis used this technique throughout his scores, it is a nice effect as it is not consistently engaged however can be a nice introduction to a new phrase or movement.

Here are some new installments in my Ring Modulation Nation project.






JPEGs from the episode:

https://docs.google.com/file/d/0B6BAUiF ... sp=sharing

Hope you enjoy