--- Steve Harris <S.W.Harris@xxxxxxxxxxxxxxx> wrote: > On Mon, Jan 05, 2004 at 06:33:23PM -0800, R Parker > wrote: > > I don't understand how impulse response (IR) > works. I > > know you fire off a sound/impulse and then the > > response is used to tell calculate the properties > of > > your room. Will IR tell me that the > average/desirable > > Sabin value from 20Hz to 4KHz for a .3 > reverberation > > time in a 17X14X7 room is 148.6? > > An impulse response is just a /very/ large FIR > filter, one way they can be > created is by a physical analysis, but thay can also > be generated > synthetically. With an IR impulse its possible to > capture and recreate any > linear (ie. non- non-linear) process, within reason. > > I see what your saying about reverb and so on v's > having a good room in > the first place, but not all audio has an acoustic > source. Absolutely. In physical rooms, the closest thing to having no acoustic source is the "Dead Room" with a flat EQ response and .1 reverberation. They are designed to not influence the EQ response and reverberation times of acoustic sources. In theory and practice no acoustic source or a source from a .1 room is very useful during the mixing stage because the engineer controls the type of room that the source appears to be within. The intent is to have the ultimate amount of control over the mix. Dead Rooms and synthesized sources help create that circumstance. Of course reverbs are then used to define the most diserable room and because the source is absolutely "dry" there's a great deal of flexibility available to the mix engineer. Ron > - Steve __________________________________ Do you Yahoo!? Yahoo! Hotjobs: Enter the "Signing Bonus" Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus
