Flo, I'm not sure why Fons suggests convolving a stereo image with a,b,c,d. Generally, what is happening in a real room is that there are many source locations: L0, L1, L2, L3, ..., Center, ..., R3, R2, R1, R0 for "simplicity." You could have them all over the room. Each of these can be considered to be a monophonic source, so the convolution would entail a left and right IR for each of these source locations, one for each ear. If you actually took a stereo image --- say from a CD --- and peformed the convolution Fons wrote about, you would hear signficant comb filtering, causing many of the timbres to be altered. I'm sure Fons knows this; I mention it because one needs to be careful about what is meant by L and R. In my own Mixster stereo convolution tool (Verbster), I don't allow convolution of stereo sources to produce stereo images for this very reason, that is to discourage users from taking a stereo image and reconvolving it. I would be open to communicating via email rather than post more here, but I really don't want to join LAD and don't read it. Regards, Dave.
