Amp Distortion

MyCo · 15 Mar 2006

you can try my feedback distortion from that project: [old link]

I haven't tried that with a guitar, but I guess it is useable, and if you attach a lowpass, you can get it much warmer 🙂

stefan · 15 Mar 2006

Adding a EQ before or after the distortion, or both, can make wonders to get a distorted tone "warm".

sambean · 15 Mar 2006

You could also try oversampling the waveshaper or whatever you are using to modify the wave..

Here's a link to an interpolation module I came up with:

http://freespace.virgin.net/cc.lai/FIR/ ... mpling.osm

Just insert the module you wish to oversample inbetween the interpolator and decimator.. the input and output of the interpolation modules has to be floats..

It comes with an example tanh function..

Cheers

Sam

stefan · 15 Mar 2006

Keep in mind though that this module only works for processes without memory. But for those, it's very usable.

andyg84 · 15 Mar 2006

Cheers thanks thats awesome very helpfull you all are. I shall be putting it up once I'm finished it so people can test it and have some fun playing with it too!

sambean · 15 Mar 2006

stefan wrote: Keep in mind though that this module only works for processes without memory. But for those, it's very usable.

Hi Stefan,

Thats what I was under the impression with at first, but after a large discussion with Kingston I realised that it works with saturated filters too.. Just plug the entire filter module between the interp/decim modules (you cant use this module to oversample a waveshaper within a filter loop, it incurrs about a 8 sample delay).

You don't get the increased frequency resolution that you would with standard oversampling but you can reduce the aliasing from the saturation..

I believe the reason that it still works is because all we are doing is oversampling the signal, convolving the oversampled signals with the IR of the filter then downsampling at the end. Any aliasing produced on the way is handled by the oversampling, but each filter is still operating on the same sample rate.

The latest version of my Soothsayer synth used an implementation of Antti's moog ladder synth with this form of oversampling, it did work well in reducing the aliasing.

Cheers

Sam

stefan · 15 Mar 2006

Ok, well, if it works it works 🙂 I still don't see how, but I haven't had the time to look it through. Or, well, I see how it handles the waveshaper within the filter, but I don't see how it handles the actual filter.

From what you say, it's almost like it doesn't oversample the actual filter part (the parts with memory), which I'd find logical.

jobro · 14 Apr 2006

Was looking for a way to distort audio, and I can't seem to find the waveshaper you are talking about. Is it in the full version or what?

The interpolation filter is quite unusable. Could you give a more precise description of how to use it? I mean just a bunch of modules with input or output module except for the direct sound module. Where should the signal be fed?

sambean · 14 Apr 2006

Hey Jobro, here's the link to the latest version of my Waveshaper:

[old link]

The progress can be charted here:

Spline Waveshaper

It's configurable through the properties window, you shouldn't have to do any tinkering inside the schematic.. Drag points off to remove/click on space to add (if option is on..)

The interpolator here:

http://freespace.virgin.net/cc.lai/FIR/ ... mpling.osm

Only works with mono connectors, that may be the problem..

Cheers

Sam