Pedalboard
©1998  Alex Chamberlain
chambera@cs.pdx.edu
http://www.cs.pdx.edu/~chambera/

This is a realtime simulation of a guitar effects processor or a set of effects pedals. The box in the lower right corner of each pedal connects/disconnects it in the signal path.  The sliders control various parameters of the sound, of course.  Yes, I know the fuzz and chorus are kind of lame, but the delay sounds just like a $150 digital delay pedal, for what that's worth!

The program (or maybe the audio_server) is very sensitive to input amplitude. You'll get nasty clipping distortion and possibly crash the audio_server if you give it too hot of an input.  An electric guitar or cheap microphone should be fine, but be careful with keyboards or other electronic instruments, as some of them put a very strong signal on their "line" output.  Remember you can also adjust the ADC input and gain with the Sound panel in Preferences.

I get good results with ADC gain on my BeBox set a couple of notches fron the top, and my guitar (a Stratocaster with EMG SA pickups) set to the middle pickup with the volume knob around 8.  Try the fuzz effect with CEILING at 0.2 and GAIN at 10.  Instant "Purple Haze!"  (Well, maybe not.)

If the sound goes away entirely regardless of what you do with the sliders, the audio_server has probably crashed.  It's not my fault—you'll just have to wait for R4 and the New Media Kit...

The delay and chorus algorithms come mostly from Curtis Roads' book The Computer Music Tutorial (MIT Press, 1997); the fuzz algorithm is my own invention.  I'd like to add a flanger but can't get it to sound decent, anyone want to help?


Revision History

0.5—March 14, 1998—First public version.


No Warranty

THERE IS NO WARRANTY FOR THIS PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
REDISTRIBUTE THE SOFTWARE AS PERMITTED IN THE LICENSING CONDITIONS,
BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL
OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
PROGRAMS (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE
PROGRAMS TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER
PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
