MF-102 as tremolo, mix knob question

Bryan T · Post by **Bryan T** » Wed Mar 08, 2006 8:18 pm

I like to use my MF-102 as a tremolo and control the mix knob dynamically. I'm a little confused by how the mix control on the MF-102 works. If I have mix set to 10 I get a nice tremolo that has a symmetrical sine or triangle wave controlling the amplitude. However, as I decrease the mix knob to bring in the dry signal the tremolo effect changes, becoming lopsided or seeming to change in frequency. Is this normal? If so, why does it behave that way?

Thanks,
Bryan

asd · Post by **asd** » Wed Mar 08, 2006 9:59 pm

i've been wondering why the tremolo works like this too. i just assumed that traditional tremolos create the effect by actually decreasing/increasing the volume of the output. but the ring mod's effect has something to do with frequencies cancelling each other so that we don't hear them. so mixing in the dry signal would change how the cancelation occured and so it seems 'choppy' or 'uneven'.

i have no idea if any that is at all true or accurate, but i got the idea (misconception? tall tale?) from somewhere.

Bryan T · Post by **Bryan T** » Fri Mar 10, 2006 5:29 pm

asd wrote:i've been wondering why the tremolo works like this too. i just assumed that traditional tremolos create the effect by actually decreasing/increasing the volume of the output. but the ring mod's effect has something to do with frequencies cancelling each other so that we don't hear them. so mixing in the dry signal would change how the cancelation occured and so it seems 'choppy' or 'uneven'

As I understand it, ring modulation and tremolo are functionally the same effect. The difference in categorization comes because tremolo uses a subsonic carrier, whereas ring modulation's carrier is in the audio spectrum.

I've been puzzling over the mix knob question and still can't figure out why the shape of the tremolo wave seems to change with the mix knob setting. Anyone else have an idea?

Thanks for responding,
Bryan

OysterRock · Post by **OysterRock** » Fri Mar 10, 2006 6:02 pm

My guess would be that it has something to do with frequencies being canceled or emphasized when the dry signal and wet signals are mixed. I think it is a great effect because you can get unusual tremolo shapes.

asd · Post by **asd** » Sun Mar 12, 2006 8:37 pm

so after a couple of minutes of googling, it seems like my initial thoughts were right. tremolo effects are based on using an lfo to modulate volume. for example (also thinking about the zvex tremolo-probe):

http://www.visionwebhosting.net/ireland ... ng0151.htm
or
http://www.hammersound.net/hs_sd_vintage_synthesis.html

this makes sense to me with guitar because a lot of tremolos have a "depth" parameter that controls how much the lfo modulates the volume and then different lfo shapes create different tremolo/volume moduation effects.

the ring mod at some points uses an audible carrier (which you can plug into in amp and use as a sound source), but also goes below that (the lfo and the carrier frequency overlap some) but that doesn't really matter for the tremolo-like effect. the 102 manual says that the tremolo effect still has two sets of pitches, they're just close together and you don't hear them as different pitches but they cancel. mixing in the dry signal would add a third pitch and so the cancelation is different (more complex?).

so even though tremolo/ring mod sound similar, they don't functon the same way. does this help?