Yeah... you're right, it's not audio related. Basically, what I want to do is to simulate the propagation of wideband pulses through coax cables of various lengths. Since I’m working with analog signals, I wanted to build an analog all-pass filter to do the job, but I quickly learned that it was very difficult. I think I’m going to go with your advice and consider using a DSP. Do you guys know of any low cost DSPs specialized for audio delays? If not, don’t worry about it, I’m going to look it up…
Also, you seem to be saying that a DSP is better than using a digital memory buffer for an all-pass filter... why is that?