28 Jan
2003
28 Jan
'03
11:05 a.m.
On Tuesday 28 January 2003 15.06, Steve Harris wrote:
On Tue, Jan 28, 2003 at 09:49:23 +0100, David Olofson
wrote:
Sounds interesting, but...
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. 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. |
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