Single Cell Software

Over the years I've worked with several hardware ring modulators, some specifically oriented at guitarists and some studio units (Moog makes some killers).

I knew the sound although there are variations. You can hear it's alot like FM can be at times, bright and chimey with tons of overtones.

What I *didn't* know was that AM at higher freq sounded so much like ring modulation. That's new to me.

After making the ring modulators it started bothering me ... the circuit as it looks would seem to indicate it's AM but I'm calling it RM. Uh oh.

Tried to find any relevant info in the Mod tutorial on YouTube and Caustic manual as well as searching the site but came up empty.

Looked at the site where I got the links above and I see this explanation where he's saying AM is extremely similiar to RM and I started thinking darn, I just found out AM can sound like RM and I'm posting calling it RM. Figured humble pie was coming.

Was worried I was about to look pretty dumb and by all rights I was, I just lucked out.

The only way to figure out what was up was to design some method to determine whether the carrier was present in the end result.

If you look at the first Mod, that is essentially what I created and was calling a ring modulator (it is). That is the reference sound for the experiment.

The waveform generator top left is the carrier. The carrier is a simple A440 sine wave. If that note/pitch is present in the output of the original design, Mod1 would have to be be Amplitude Modulation. If it gets eliminated before the output it would be ring modulation.

If you solo and play Mod1 your hear the test subject.

If you solo and play Mod2 you hear the carrier.

Now look at the design of Mod3.

Identical to the first Mod to be tested with one exception - there is a mixer in the top right corner. If you look carefully you will see I have wired the output of the waveform generator to Input 1. That is the carrier.

Then note that I have taken the wire that used to go to L-Mono output and instead routed it to the new mixer, Input 2. Top right, directly below the outputs.

Turn up Input 1 - carrier
Turn up Input 2 - sum and difference frequencies

http://synthesizeracademy.com/ring-modulator/

explains sum and difference vs carrier. But you don't need an oscilloscope for this experiment.

Again be sure to Solo Mod3 or the experiment is contaminated. Press play. While it plays raise and lower the Inputs 1 and 2 and listen to them. Separately. Together. As many times as necessary. Clearly the carrier is *not* present which demonstrates it is in fact RM. Pretty sure if I rendered it and checked with the Spectrum analyzer in the wave editor out would be confirmed. When I post the follow test shortly you will no doubt hear the difference when the carrier is present in the test subject.

That raised a bunch more questions that I had to figure out (I have now, whew) which I'll answer soon. The answer, and what tipped me off, was the fact that the MiniLFO has 2 different outputs. The key to this lies in polarity. Trust me, it's not nearly as complicated as you think.

And JH you're not slow, there isn't a ton of available documentation on how the Mod units function in Caustic but it's unfortunate because it turns out to be brilliant how the AM and Mod inputs work- they can perform both AM and RM depending on the type (+ or - value) of input.

If you look again at the link above there is a picture of a Morpheum VCA and a bit about it. Turns out the AM and Mod Inputs function very similarly.

Here's a little example that will explain a few different strategies about Edit: blah blah blah... removed and included in the long diatribe below.

Uh oh. This will surely be a snoozefest.

Next up, a little explanation of how these Ring Mod setups work.

In these examples either the drums or bass are the carriers and the two or three wave generators at the bottom of the Modsynths are the modulators. Each is using an external source as the input - think of these RMs as FX units. You can create and pull up the Modsynth presets in any project and shove any synth you want you want thru them. Or remove the machine input and add another waveform generator in as a carrier.

For the ring modulators to work you have to tell the modulators, the waveform generators, what frequency to run at. You do that by putting notes in the Modsynth piano roll. Or playing the keyboard.

The first combined setup is the Beatbox and RM1. The BBox is the carrier which goes to the machine input of RM1 which contains two modulators at the bottom

When you start playing the first 16 measures there is no sound coming from RM1 although you can see the Beatbox is working away. That's because the ring modulators aren't getting a signal. They are receiving the carrier but no Note CV signal to tell them what freq to operate at.

There are notes visible in the Drum grid so the carrier is getting a Note CV but there are none in the RM1 Modsynth.

As the first 16 bars play start pressing keys on the RM1 keyboard and you hear the modulators working, you hear ring modulated drums.

Note that there is no special relationship in this case between the frequencies of the carrier and modulators; the modulators are not fixed because everytime you play a key and send a CV signal to the modulators the carrier is getting its own. The frequency of the modulator is not "fixed" (staying on one single freq) because you are playing it - unless you just hold one key down for the entire duration - nor is it likely following the freq of the carrier.

When the next section starts playing at measure 18 the same Beatbox is now being used. This time the BBox is being fed into RM2.

If you look at Modsynth RM2 there is a single 16th note on C3. That is serving a dual purpose. Since the "Send Notes To Source" button is activated it's telling the BBox to play the Kick drum.

Note: the 8 BBox drums respond to the notes C3 up to B4. This means that if you play any note in the Modsynth outside of that range no drum pad will be triggered and only RM waveform generators will sound.

But wait... That doesn't sound like a kick at all. That's because the volume of the BBox is turned down on the mixer, you are not hearing the carrier, you are hearing the end result of the carrier and modulators being multiplied.

The center waveform generator is automated. As the octave of that modulator (there are 3 ring modulators in this Modsynth) changes and therefore the freq, the overtones produced change.

When the next section starts playing, the exact same notes used in the BBox at the beginning of the song are now visible in the piano roll of RM2.

Again they serve a dual purpose as each note triggers a drum, the carrier, and also the modulators. Since the same Note CV is being sent to both, the modulator is not "fixed", it's is "following" or receiving the same CV as the carrier.

In reality that's not generally a big deal here as drums kits and may other percussive sounds don't produce notes that behave in a manner like most synths, they are not pitched in semi - tones etc.

However, what if you feed an instrument like a bass into the ring mods? If you give the same CV to the carrier as the modulator then the overtones follow the original sound and often seen less harsh of metallic and more musical.

That's not good or bad it just depends on the effect yu want to produce.

Next up is some bass from the SubSynth, no RM, the notes are in the SubSynth piano roll. This time the ring modulation will come in on top of the bass and then drums. These examples are absolutely not tuned to sound any particular way so don't expect something that is musically pleasing at the moment (although that is rather subjective).

This example ends with the SubSynth playing thru RM4. This is to demonstrate another approach to using RM which is essentially where the example began and you "played" the ring modular on the keyboard.

Since the SubSynth is getting the Note CV from it's own piano roll, you can play around with the notes sending the CV any way you like. Glide them, use the Arpeggiator; you can play them like a seperate instrument.

There is an 8 bar C1 note slowly gliding up to C5. You can distinctly hear the overtones from the ring modulators gliding up as the bass just does it's thing. The modulators are not fixed or following the Note CV of the carrier and it creates it's own distinctive effect.

You can also control whatever you want to with the (ring) modulators in the Modsynth. Stick LFO's or envelopes on the pitch or the FM inputs, add a mixer and combine the machine input and modulated output inside the Modsynth and crossfade or pan that with an LFO; pretty flexible.

Tweaking or automating the Octave, Semi and Cents of the modulators is a must. Changing the waveform from sine to saw and square. The only way to get a feel for them is to shove a signal in and play around.

Hmmmmm...... so here's some actual AM. I think. Still have to measure it. Just chopped the negative samples out of a sine waves and looped it, put it in the wave editor. Not as smooth as a sine wave but it seems to work.

If anyone else feels like messing around here's a simple setup.

@paulovski Sorry, not ignoring you. For some odd reason your posts aren't appearing to me till a few hours after the fact. Thanks for the input and throwing that together. Will try to make wrap my poor overtaxed brain around it.

Deleted repost

Wow, major breakthrough tonight. I just wasn't getting it so I went back and re-read the Ultra Low LFO and UMF thread and the bulb went off.

Bring a musician I was thinking of everything as an audio path with modifiers but the difference between the concept of the AC DC wasn't there.

Obviously you guys get this already but for the sake of making sure I have this right so far, please correct me anywhere I'm off.

So essentially all the CV are DC and all the Osc are AC.

The Env are just DC modifiers.

The filters have several different effects on "attenuating" (yeah, I know, audio term) the DC depending on the filter. Some notable points being the neg bias of the BP and the ability to use the Resonance control as a manual attenuator.

And the freaky 50/50 attenuation of the Vintage Ladder although I can't really see how it's odd behaviour would be advantageous.

Anyways, the attached caustic file is pretty self-explanatory.

Good analogy, alot of the time (most) when I use the vocoder it's together with another synth.

The difference? TheModSynth is a completely different beast. Both are really powerful and take time to get to the point where you can really exploit.

The ModSynth is insanely flexible though, you can use an envelope like an LFO and an LFO like a cheap handyman.