[linux-audio-dev] Simple reverbs

[David Olofson]

On Tuesday 28 January 2003 15.06, Steve Harris wrote:
> On Tue, Jan 28, 2003 at 09:49:23 +0100, David Olofson wrote:
> > Thoughts? Any ideas for useful cross feedback configurations?
>
> One of the waveguide papers gives the maths to use for stable
> feedback matrix values, its pretty obvious from what I remember,
> just make |A| = 1.0. Adding an allpass at the junctions will make
> it sound smoother.
>
> I have a perl script that can create arbitrary matrixes + filters +
> delay lines from a description of the surface network, which is how
> I built the gong and plate reverb models. Interesting surface
> shapes (eg. bow tie) can produce interesting (and quite
> predictable) sonic results.

Sounds interesting, but...


> You have to be careful because some of this stuff is covered by the
> Karplus/Stanford/Yamaha patents. IIRC non commercial use is
> allowed.

Damn. That means I can't have a reverb in an LGPLed engine, or are 
there other, useful ways of doing it? I mean, how would one go about 
*not* doing it with feedback delay lines in roughly one of the 
configurations covered by the patents...?

Reinventing this without having seen these designs hardly helped, as I 
ended up with the same design anyway. This reminds all too much of 
this direct-from-disk sampler thing...


//David Olofson - Programmer, Composer, Open Source Advocate

.- The Return of Audiality! --------------------------------.
| Free/Open Source Audio Engine for use in Games or Studio. |
| RT and off-line synth. Scripting. Sample accurate timing. |
`---------------------------> http://olofson.net/audiality -'
   --- http://olofson.net --- http://www.reologica.se ---