What is a wavefolder? Can you make one from other modules?

[Devilwidget]

My system is lacking a wavefolder, and I would like to know how they actually work, rather than just buying one for the effect. What are they actually doing? What is happening to make sine wave 'fold' over in the way it does? Can I do this with other modules?
thanks!

[Bobby]

....search and you will find

[Devilwidget]

As helpful as that is, could you suggest a search term? I'm just getting "what's your favourite wavefolder" threads, which isn't quite my question...

[pre55ure]

My system is lacking a wavefolder, and I would like to know how they actually work, rather than just buying one for the effect. What are they actually doing? What is happening to make sine wave 'fold' over in the way it does? Can I do this with other modules?
thanks!

Wavefolding basically "reflects" the waveform back on itself. So as a sine or triangle wave get larger in amplitude, instead of just clipping the top and bottom (and looking more like a square wave) the wavefolder flips the direction and the upward slope now becomes a downward slope etc. If you continue to increase the amplitude (or lower the threshold) then the wave will hit the opposite threshold and get reflected again. Additionally most wavefolders have some type of diode or transistor stages so that they don't just perfectly reflect but instead have a bit of nonlinearity in the reflections.


I hope thats helpful, I've built a couple of clones of the Buchla timbre circuit and the serge wavefolders (and they both work in a very similar manner) but I'm not quite sure if that description is too technical or not technical enough.

Edit: Forgot to try to answer the question - Can you do this with other modules - probably. But I'm not quite sure if there is a way to do it without using a lot of different modules.

[pre55ure]

Ok after a quick thought at how you could do this...

Maybe you could run an osc through an attenuator and into dual comparators.
set the comparators so that they are just above and below the waveform peaks. Then run the comparators out to the selection input of two sequential switches. Meanwhile run the waveform out to an inverter and then mult the regular waveform and the inverted waveform and input these into the sequential switch inputs. Then mix the two sequential switches back together. I think that would result in a patch where as you turned up the initial waveform it would trigger the comparators to flip between the sequential switch inputs and give you the "reflection" of the waveform.

[BaloErets]

Check out Danjel's vid showing off the ufold. Should become perfectly clear if you watch the oscilloscope.

[video]

[/video]

[Devilwidget]

Great answer pre55ure!
I was thinking I should buy a comparator anyway...

[Dr. Sketch-n-Etch]

Yes, normally when a signal hits the rails (in an opamp), it disappears (which converts everything into square waves). In a wavefolder, the opamp's rails become reflectors. If the opamp has enough gain, the wave will reflect off of one rail, go to the other rail and reflect off of that, and do this several times. In the uFold, this happens up to six times.

[BaloErets]

Ok after a quick thought at how you could do this...

Maybe you could run an osc through an attenuator and into dual comparators.
set the comparators so that they are just above and below the waveform peaks. Then run the comparators out to the selection input of two sequential switches. Meanwhile run the waveform out to an inverter and then mult the regular waveform and the inverted waveform and input these into the sequential switch inputs. Then mix the two sequential switches back together. I think that would result in a patch where as you turned up the initial waveform it would trigger the comparators to flip between the sequential switch inputs and give you the "reflection" of the waveform.

Amazing!

You see, this is both what makes modular so amazing, and a great example of why utilities are so important.

[noeticsound]

Ok after a quick thought at how you could do this...

Maybe you could run an osc through an attenuator and into dual comparators.
set the comparators so that they are just above and below the waveform peaks. Then run the comparators out to the selection input of two sequential switches. Meanwhile run the waveform out to an inverter and then mult the regular waveform and the inverted waveform and input these into the sequential switch inputs. Then mix the two sequential switches back together. I think that would result in a patch where as you turned up the initial waveform it would trigger the comparators to flip between the sequential switch inputs and give you the "reflection" of the waveform.

Amazing!

You see, this is both what makes modular so amazing, and a great example of why utilities are so important.

Yeah, that paragraph is a master class. No joke, I actually feel smarter.

[Bobby]

http://letmegooglethat.com/?q=what+is+a+wavefolder

[Bobby]

http://www.freedomscientific.com/traini ... ngines.htm

[satori]

Bobby, you're just being a douche..

[Clive]

To pick up on what pre55ure and the Doc have said and to answer the OP, yes, you can, but you might as well get a proper wavefolder:

Fold a sine once and it will sound slightly nasal, fold it six times and all manner of tones are possible. A circuit like the classic Serge design uses diodes to set thresholds - they are essentially multiple comparators.

If you want to get a sonic taste of wavefolding, try hard sync, where the slave is a triangle. The greater the difference in frequency between master and slave, the more 'folds'. The crucial difference is that with wavefolding, you can change these harmonics dynamically, like an inverse filter.

[Bobby]

Bobby, you're just being a douche..

actually it would appear that way but i do quite strongly believe that if you teach a man to fish, he can just fish, teach him how to use a search engine and he can do anything his mind is capable of.


edit: plus this community/threads would be a damn site better if people picked up where others left off rather than this groundhog day shit, you notice the top google hit for "what is a wave folder" was muff wiggler right....

[Devilwidget]

Fair enough Bobby, however, the first thing I did was search on muffs. These threads are buried within 1000 other threads that don't give this info. I didn't think of trying google because a) I try not to use it (they are quite a naughty company and there are ethical implications to using their service), and b) the fundamental premise of research is to target your search (i.e. by using a forum like muffs).

I would also suggest there is little point in a community if all it does is simply refer its members to the concept of existing information. There is a reason muffs has such a good reputation, and that is precisely because many of its users are more than happy to answer potentially well-trodden questions.

I am also yet to find (having now looked at the links you so sarcastically provided) any other description about how it might be possible to construct your own wavefolder from other modules, which was my question. I am extremely glad that someone was able to provide - and others are benefiting from - an answer to that question.

[Bobby]

Loads of great suff here bro:

https://www.google.co.uk/search?client= ... m&safe=off

peace & love

edit: btw i still feel I'm/google is helping you more than anyone in else in this thread

edit2: I'm actually sorry if I've come over badly too, i am really trying to help in my own grotty way. apologies.

[guestt]

Ok after a quick thought at how you could do this...

Maybe you could run an osc through an attenuator and into dual comparators.
set the comparators so that they are just above and below the waveform peaks. Then run the comparators out to the selection input of two sequential switches. Meanwhile run the waveform out to an inverter and then mult the regular waveform and the inverted waveform and input these into the sequential switch inputs. Then mix the two sequential switches back together. I think that would result in a patch where as you turned up the initial waveform it would trigger the comparators to flip between the sequential switch inputs and give you the "reflection" of the waveform.

Amazing!

You see, this is both what makes modular so amazing, and a great example of why utilities are so important.

Yeah, that paragraph is a master class. No joke, I actually feel smarter.

+1 thanks for this, really nice work!! I was sat wondering how it could be done and I think it would have taken me some time to work that out

[Footkerchief]

A full-wave rectifier is kind of like a simplistic wavefolder. In fact there's a cool rectifier module that sounds kind of like a subtle wavefolder:
https://www.modulargrid.net/e/barton-mu ... -rectifier

[video][/video]

[ScubaGeek]

I would also suggest there is little point in a community if all it does is simply refer its members to the concept of existing information. There is a reason muffs has such a good reputation, and that is precisely because many of its users are more than happy to answer potentially well-trodden questions.
.

That's why I've always disliked the whole "Google is your friend" attitude. It seems to me that the whole point (or one of the main points, anyway) of a site like Muff Wigglers is share whatever knowledge person has with everyone else, and there are times when simply saying "Use the search engine" doesn't get the job done.

If you're unhappy about the existence of "Groundhog Day" threads, then don't participate in them, You Big Dummy! Why is that so difficult for some people? Probably the same reason it's difficult for people to not post negative threads about stuff they don't like (eg is it really necessary to post on a thread just to say "Man, that band sucks").

[guestt]

Cut to the chase lets just call each other cunts and shout and scream for a bit...


...all better now?

Seriously, without wanting to do the whole whining about whining about whining thing, which I very obviously am, this kind of rotten shit really fucking pisses me off!!!

Either talk abut the gear or shut the fuck up!!



edit: I am talking to myself as much as anyone, any more of this fucking crap and I am out of here because I am sick to the back fucking teeth of it!

[Dr. Sketch-n-Etch]

Ok after a quick thought at how you could do this...

Maybe you could run an osc through an attenuator and into dual comparators.
set the comparators so that they are just above and below the waveform peaks. Then run the comparators out to the selection input of two sequential switches. Meanwhile run the waveform out to an inverter and then mult the regular waveform and the inverted waveform and input these into the sequential switch inputs. Then mix the two sequential switches back together. I think that would result in a patch where as you turned up the initial waveform it would trigger the comparators to flip between the sequential switch inputs and give you the "reflection" of the waveform.

This is way more complicated than a proper wavefolding circuit, which is actually quite simple.

[guestt]

Yeah, very true Dr. Sketch-n-Etch

The idea was to create it using other modules though. I've been trying and can't think of any other way, well nothing significantly different from the way presented by pre55ure anyway

[Paul Perry]

If you overdrive a signal in an amp, you get a flat top wave as output..
Now if you add to this the same signal, undistorted and at a lower level and out of phase,you will get a folded wave. (the 'peaks' in the undistorted wave will subtract from the flattened wavetops.)

I think sometimes people expect too much from a wavefolder, if they expect it to make a single tone amazing - yes, it changes, but the harmonic mix is changed, but no new frequencies added. On the other hand, if you have two or more different fundamentals going in, then you get a ring modulator kind of effect. Cheap thrills!

[pre55ure]

If you overdrive a signal in an amp, you get a flat top wave as output..
Now if you add to this the same signal, undistorted and at a lower level and out of phase,you will get a folded wave. (the 'peaks' in the undistorted wave will subtract from the flattened wavetops.)

That seems like a much simpler way than what I suggested.

I think sometimes people expect too much from a wavefolder, if they expect it to make a single tone amazing -

I can't argue as to what other people expect from a wavefolder, but to my ears the Buchla timbre section (particularly the one in the 259) is one of the most awesome sounding things ever. I totally think it makes a single tone amazing. The Serge one isn't too far behind either (to my ears).

[Graham Hinton]

Can I do this with other modules?

I have put together a page of waveshaping applications using our ModMix II which comprises two mixers with positive and negative half wave rectifiers and two linear multipliers. The examples show ways of combining these elements to perform different operations and are by no means exhaustive or exclusive if you have the equivalent elements in other modules.

Basically anything that changes the shape of a wave changes its harmonic structure and you get more and higher harmonics if you introduce discontinuity points and asymmetry.

[Dcramer]

Can I do this with other modules?

I have put together a page of waveshaping applications using our ModMix II which comprises two mixers with positive and negative half wave rectifiers and two linear multipliers. The examples show ways of combining these elements to perform different operations and are by no means exhaustive or exclusive if you have the equivalent elements in other modules.

Basically anything that changes the shape of a wave changes its harmonic structure and you get more and higher harmonics if you introduce discontinuity points and asymmetry.

tons of great info here!

My only advice about Wavefolders and shapers is simply that just like filters they all have there own character, collect em all!

[Footkerchief]

I think sometimes people expect too much from a wavefolder, if they expect it to make a single tone amazing - yes, it changes, but the harmonic mix is changed, but no new frequencies added.

Is this a meaningful distinction?

[Recitative]

New frequencies are added as overtones. No new fundamental frequencies are added.

[guestt]

Can I do this with other modules?

I have put together a page of waveshaping applications using our ModMix II which comprises two mixers with positive and negative half wave rectifiers and two linear multipliers. The examples show ways of combining these elements to perform different operations and are by no means exhaustive or exclusive if you have the equivalent elements in other modules.

Basically anything that changes the shape of a wave changes its harmonic structure and you get more and higher harmonics if you introduce discontinuity points and asymmetry.

tons of great info here!

My only advice about Wavefolders and shapers is simply that just like filters they all have there own character, collect em all!

Niiiiiiiiice! Thank you Graham!!

...and +1 to wave folder characteristics all being very different. I only have one module sell regret so far and it is the Random*Source Serge Wave Multipliers - I am going to build another one, I miss it too much!!