13 Feb
2007
13 Feb
'07
6:41 p.m.
Hallo!
Usually acoustic measurements are done with impulses, AFAIK. An
ideal impulse actually has all frequencies in it, so it's useful for
that kind of thing. Plus it's easy to differentiate between the
initial signal and the room effects just based on time.Actually I think, engineers prefer to use frequency sweeps instead of pulses nowadays. The problem with pulses is, that they are hard to get right: You need a clean pulse and a very silent environment:
Well, there are also problems with swept sines of course ... ;)
Other methods are e.g.
- with MLS (http://en.wikipedia.org/wiki/Maximum_length_sequence) - I
think there is also an mls example in the iem_tab library. -Least Square Error methods (see system identification example in the adaptive library)
- with noise (more energy than in a dirac impulse)
- auto-, crosscorrelation methods
- ...
LG Georg