KVR Audio

Jafo · Post by **Jafo** » Sat Nov 26, 2005 3:41 am

There are plenty of waveshapers (Cyanide, etc.), but it seems they all produce waves that are symmetrical in their positive and negative phases -- there's a lot of math involved (none of which I can ever hope to understand, alas) which shows that the distortion thus produced is purely odd-order. Now, I have no problem with this; great sound is great sound no matter how it's produced, and square waves are cool. However, I'm after a slightly different sound, one with even-order harmonic distortion. You can call it more like a tube distortion if you want, but even tubes produce mostly odd-order harmonics so you'd be wrong

. Such an effect would vastly increase our waveshaping possibilities, and might even sound good!

I suppose one could just split the input, rectify both, invert the negative, waveshape both waves independently, invert the original negative, and combine, but there'd probably be all sorts of crossing errors unless one took great care to keep the two synced -- but how would you make sure they align after shaping both?

*shrug* Don't mind me, I'm no programmer -- just thinking out loud. It's way beyond my ken (and my Barbie, and all my action figures as well).

The Chase · Post by **The Chase** » Sat Nov 26, 2005 3:46 am

a dual unipolar waveshaper (one for positive and negative) would be awesome. Sounds like something that Jack Dark would come out with...

WINK WINK NUDGE NUDGE JACK DARK

shamann · Post by **shamann** » Sat Nov 26, 2005 3:55 am

The default waveshaper in Synthedit is asymmetric. I don't know of any others. Wish I did though, since I don't think the SE one does internal oversampling. I also find it a bit fiddly to use.

The Chase · Post by **The Chase** » Sat Nov 26, 2005 3:57 am

the SE waveshapers is bunk and drives me insane as you can only drag the pre-existing points..

aciddose · Post by **aciddose** » Sat Nov 26, 2005 3:58 am

actually the solution is simple, apply a dc offset at the input, and remove it at the output, although the output may have dc removal already.

people actually like tube circuits not for the preformance of the tubes, but for the design used.

the asymmetrey is caused wholey by the dc offset in the amplifing circuit.

the difference between tubes and transistors in this example is most noticable. in a balanced amplifer there is no noticable difference.

Borogove · Post by **Borogove** » Sat Nov 26, 2005 4:23 am

Tiny Distortion has different curves for the positive and negative side of the distortion, but you'll have to figure out which of the cryptically named knobs controls them.

Jafo · Post by **Jafo** » Sat Nov 26, 2005 4:54 am

My spies inform me that aciddose wrote:actually the solution is simple, apply a dc offset at the input, and remove it at the output, although the output may have dc removal already.

Way cool! This would work just as well in hardware as software. Thanks.

aciddose · Post by **aciddose** » Sat Nov 26, 2005 5:06 am

actually most of the time in hardware the input will have a capacitor in line, so it wont work as well.

i actually designed a basic soft clipper which has bias adjustment built in, i have yet to build and use the circuit but it works really nice under simulation.. i really need to finish my modular psu so i can get all the circuits i want working and show demos to people :)

soft saturation occurs by a combination of the buffers and the common base amplifier, i'm not sure as to the real world performance of it yet. i assume when i test this circuit in the real world it will have some kind of problem, since nobody else seems to use it. also, the 10k offset pot should be 100k, actually dont even try using this, simulate and rework it yourself first. (to anyone who might actually consider it)

The Chase · Post by **The Chase** » Sat Nov 26, 2005 5:54 am

impressive

kylen · Post by **kylen** » Sat Nov 26, 2005 7:16 am

Sony (formerly sonic foundry) has a distortion plugin that'll do it:

"Distortion—Edit distortion curves with complete flexibility with a graphical interface that features discrete settings for positive and negative signal polarity and an integrated variable low-pass filter. Add further realism with variable slew rates."

http://www.sonymediasoftware.com/produc ... ureID=1486

It's fun to play with and using an oscilloscope you can see the shape of the pos/neg cycle. I keep comin back to the Voxengo Tube Amp, Ozone3 MB distortion - and just picked up 4Front exciter. I'm always looking for those golden harmonics though - keep 'em comin!

lion_cub · Post by **lion_cub** » Sat Nov 26, 2005 12:55 pm

ZynAddSubFX has asymmetrical waveshaping

Jafo · Post by **Jafo** » Sat Nov 26, 2005 1:32 pm

My spies inform me that lion_cub wrote:ZynAddSubFX has asymmetrical waveshaping

Perhaps. But its author demands certain beliefs, and I cannot condone any sort of imperialism, especially not metaphysical or cosmological. No mind can encompass everything, and to believe that one's experiences and beliefs are necessarily better than another's is laughable at best.

Besides, I plan to do a bit of heavy metal, which directly violates the license.

lion_cub · Post by **lion_cub** » Sat Nov 26, 2005 1:47 pm

Jafo wrote:
My spies inform me that lion_cub wrote:ZynAddSubFX has asymmetrical waveshaping
Perhaps. But its author demands certain beliefs, and I cannot condone any sort of imperialism, especially not metaphysical or cosmological. No mind can encompass everything, and to believe that one's experiences and beliefs are necessarily better than another's is laughable at best.

Besides, I plan to do a bit of heavy metal, which directly violates the license.

Your loss.

Asymmetrical Waveshaper?