[linux-audio-dev] [OT] Question about some definition..

[Vincent Touquet]

On Sat, Jun 14, 2003 at 12:12:37AM -0300, Juan Linietsky wrote:
>Hi! i'm doing some studying on dsp, and one thing I could never properly
>understand is the term of "excitation signal" I seem to find it associated
>to environment or natural sources, but I cant really find a definition.
>Could someone with enough knowledge on this subject please
>give me a brief on this? Thanks in advance!

To me, an excitation signal is like a pulse, or a step function, which
you can use as an input to your system. What comes from the output, you
can then use to derive the transfer function of your system, which
completely determines the sound of it.

Eg. if you manage to record how a cavity reacts to a pulse, you can
simulate that environment for other sounds too. 

This more or less assumes linear characteristics though.
Non linear systems are more difficult to identify (to create a model
of), and unfortunately most interesting things happen when non
linearities are involved (tube amps, analog Moog synths).

hope that more or less clears some things up

v