Can MF-102 do both tremolo and vibrato?

The Moog Forum Moogerfooger Forum
1

Hi there!

I am a bit confused about the MF 102 and the “tremolo/vibrato” effects it is supposed to deliver.

Can the MF 102 be set up to do tremolo according to this definition (from Wikipedia):
"A regular and repetitive variation in amplitude for the duration of a single note; this is the most common meaning. "

AND can it be set up to do vibrato according to this definition (also from Wikipedia):
A variation in pitch, slow or rapid, during the duration of a note.

(both definitions can be found here: http://en.wikipedia.org/wiki/Tremolo)

If it can produce both effects then how does it perform compared to a dedicated tremolo and vibrato pedal like this:

http://www.proguitarshop.com/product.php?ProductID=378&CategoryID=

And how does it do it? (I understand that the tremolo is done by some sort of sound cancelation - not simply by modulating the output volume). I’d be happy to get some explanations on how the effects work and is set up on the unit.

Any help on this would be appreciated! :slight_smile:

-Lyserk

2

Actually, it IS that simple.

The internal oscillator on the MF-102 is being used to modulate the amplitude (volume) of your input signal. When the rate of the oscillator is up in the audible range (above 40Hz or so), you get the “ring mod” sound. When the speed of the oscillator is much slower, you get the “tremolo” effect.

The MF-102 will not modulate the pitch of your input signal in the way that VOX pedal is doing it, so “vibrato” effects by that definition are not possible. If someone says “vibrato” when talking about the MF-102, they are probably confusing it with “tremolo”.

3

errr. it is almost that simple…

it is more similar to the beats you hear when tuning, and each pitch is slightly out from each other.

when the pitch of the ring mod is close to the sound you are playing the destructive and constructive interface phases in and out of sync… the closer the 2 pitches are the slower it goes. as your pitch moves away the speed of the tremolo increases till it enters the audio range.


The same idea also holds true when intervals are mathematically lined up (5ths 4ths octaves, etc.) so each note and each pitch will have different rates of tremolo.

4

this describes it better than I can.


http://www.glenbrook.k12.il.us/gbssci/phys/Class/sound/u11l3a.html


so when in phase it is like a volume boost, when out of phase it is like a volume drop.

5

Matt,

Everything you describe is correct, and all of that happens when the carrier signal is up in the “audio range” (i.e. sounds our ears can hear, typically 40hz and above). This is the definition of a ring mod effect, and it is how all ring mods work.

However, it IS true that what is technically going on in the circuit is just VCA being modulated by a carrier signal. Amplitude modulation, that is all. The fact that it is being modulated by an audio-rate signal - this is what produces the secondary waveform that you can actually hear “beating” against the pitch as you play, and the two waveforms cancel and multiply in the manner you describe.

BUT, when used as a tremolo effect (when the carrier signal is slower, well below 40Hz) you’re not going to hear any waveform cancellation or anything like that. The pitches you are playing at the input (from a guitar, synth, whatever) are going to be much, much higher than 40Hz.

If you turn the oscillator on the MF-102 down low, say to 2Hz, you get a tremolo effect that modulates the volume of your signal up and down twice per second. A 2Hz waveform is not audible to our ears, so the only thing we hear is the volume going up and down. No matter what notes you play on your guitar or synth, from the highest range to the lowest audible signals, the pitch of your input signal will come out the same pitch as it came in. All you will hear is the volume being modulated up and down twice per second. The speed of the tremolo effect (2Hz) will not change if you play a higher or lower note on your instrument.

6

What about vibrato. If you fun an LFO from a fooger into the frequency in of a freqbox, at sub audio levels you should get vibrato right?

7

OK, I get it now :slight_smile:

Thanks for your replies!

Regards

Lyserk

8

What about vibrato. If you fun an LFO from a fooger into the frequency in of a freqbox, at sub audio levels you should get vibrato right?

That’s right. Tremolo is an amplitude modulation, and vibrato is a frequency modulation. What makes it confusing is that some manufacturers don’t follow this usage in naming their products (like the ‘tremolo’ arm on a guitar, which is really vibrato). Tremolo circuits are much simpler than vibrato circuits, which is one reason they are more common. If you want true vibrato in pedal form, the best bet (IMO) is to get a chorus or phaser type pedal which has a switchable vibrato mode.

9

soundxp,

we are just having fun with the depth of this pedal- as there is more than 1 way to get the “tremolo..” :sunglasses: I will have to better define my vocab and use of this pedal for future reference…


The “ring mod” tremolo I and my close group of friends have always used and I guess always associate with it’s primary function is based off the audio range interference… it is a tremolo with very FUN and deep preperties

I guess I always see the slower LFO range (like a VCA) to be the secondary function of it… i may be in the minority though…

10

I think that I have seen someone awhile back state to me that tremelo is essentially just a secondary function of a Ring Mod.

I bought mine to replace the nonfunctional tremelo of my Rhodes (Which uses a photo resistor…you might find that interesting) and I remain impressed with what it will do. I use it just about every time I start to do any kind of “Modular patch” because it has that telephone like computer sci-fi bleep bloop madness (when used with a synth lead) reminiscent of Floyd and others.

Now I can see having more than one but I can’t see paying for a second one anytime soon.

There have been several times I have overdubbed ring modulation of various types (Slow sine, tremelo and processing synth leads) so I can definately see the need for more.

11

well, food for thought.


if you run a lowpass with resonance AND a LFO into the audio range you get ringmodish type sounds… I will use this some times to make a more subtle ring mod distruction :slight_smile:

most people here have a lowpass and some way to get an osc into it. try stacking your ring mod effects that way to get more at once, or to color them differently…

12

I’d like to hear an example of what you are talking about.
I think we both understand how it works, we’re just using different terminology in some instances. :smiley:

For me, “audio rate tremolo” is the same thing as “ring mod”.
Same effect, different speed for the carrier signal.

With all other settings the same:

Turn the Rate knob up = ring mod
Turn the Rate knob down = tremolo

I should also point out that I don’t have an MF-102. I use a Frostwave Blue Ringer instead. While it doesn’t have as much CV control, it functions like the MF-102 and sounds excellent as well.

Here’s a YouTube video I posted several months ago. It starts out with a tremolo effect, and then goes up into ring mod territory when I turn the Frequency knob up.
http://www.youtube.com/watch?v=60DM_38vCVA

13

A few things I wanted to clarify and I hope I get this right. Please correct me if I am wrong.

First, ring modulation is related to amplitude modulation. In amplitude modulation, a sin wave is used to change the amplitude of the carrier signal which is the equivalent mathematically of multiplying the signals. the process itself if known as heterdyning and produces two “sidebands”, one at a lower frequency and the other at a higher frequency at equal distance, equal to the bandwith (inverse of frequency) of the modulating sin wave.

FM does something similar but produces multiple side bands which are related to the amplitude of the modulator. More volume, more sidebands which is exactly what happens with natural musical instruments. For example, a trumpet played at low volume is darker but when louder it has a brighter sounds. With tonguing, one can get a lot of expression by chaning the transient. FM synths mmic this which is why the Yamaha FM7 was so sucessful and even its later soft synth equivalents.

Ring modulation is related. It gets its name from the circut that produces it which is a circut with a diode on each side of a sqare which forms the ring.

Now what is interesting in either Frequency modulation or ring modulation is that the ratio of the two fundamental frequencies and their overtones combines to create a complex spectrum. I they are of the same frquency and waveform then the spectrum is doubled (or raised an octave to simplify).

Now with other frequencies, the frequencies of the side bands become the sum and diference of the frequencies but usually with the original signal removed which gives it its unique character.

Ratios of the fequencies which are whole numbers create more harmonics tones reminiscent of musical instruments but with fractional ratios, the tones sound more and more bell like and inharmonic. Some of your more “spacey” sounds can be created this way especially with a bit of reverb added.

A true master of ring modulation is Karlheintz Stockhausen especially his renown Kontakt found here of no doubt for which the Native Instruments sampler owes its name:

http://www.youtube.com/watch?v=aNt6a5xFOnE

or his later work “licht” (German for light), for which I believe the work of the series has been completed.

Another master at this is Morton Subontick. Subotnick used something called a “ghost box” which consisted of a pitch and envelope follower, a VCA and a voltage controlled ring modulator and frequency shifter.

What is interesting is that the pitch follower, I presume, was analogue so it would be nice to have a pitch follower in a fooger along with a frequency shifter or even a multiple frequency shifter like an EH POG. Of course the EH POG does not have CV control.

Clearly, the history in electronic music and even jazz (Miles Davis and Chic Corea on a Rhoades) has made significant use of ring modulation which is why I find it interested that the best use people find for these is running a drum machine through them.

14

Chick still uses a Voyager and RingMod today.

15

fwiw i don’t have the mooger ring mod either… but..


http://soundclick.com/share?songid=7510201

is a 5 second sample i patched .. you can hear the phasing tremolo. had i changed pitch, the trem rate changes with different notes…


http://soundclick.com/share?songid=7317722

at :37 has this effect being used on violin..

16

Nice effect! One of the first uses of a fooger that is musical and not a sound effect that I have heard (referring to your 2nd link).

17

Has anyone else found that when you first get a new effect unit, you play the thing with wild exageration and get weird sound effects. Then as you get more familiar with the controls you end up using them much more subtly and musically?

18

Exactly! I don’t think the newness of my Theremin has ever worn off lololololol. Cause I am not that musical with mine as a solo instrument. I do better accompanying other things.

Eric

19

Yes, I always try and effect for a few days and find the full range of what it can do and then narrow down on a range of settings that work for what I want to do with it.

20

I tend to be geared towards creating sounds that are more experimental, as I am sure you can tell from my videos. I like making noises more than music, although “music” is a broad term. Take John Cage for instance. :confused: