Thanks for the heads up on this. One of the problems with using simple subtraction of two recordings is that the time synchronization will never be spot on, thus yielding a measureable difference when no difference really exists. Thus, when I saw the phrase "Precisely align two similar audio tracks to the same gain levels and timing" on the webpage linked, I got excited.
So, I downloaded the program and installed it. I was encouraged to find a setting in the setup diaglog box that allowed me to set delay resolution to 100ps. I opted for 1ns of delay resolution in the Time Alignment box. To test out the effectiveness of this, I figured I'd do a simple test. I generated a couple files of a 1kHz sine wave at -10dB. The reference file had 0 degrees of phase shift, and the compared file had 4 degrees. This makes for about a half a sample of delay in the compared file with a sampling frequency of 44.1kHz. If a straight subtraction were done in my audio editor (without time compensation), I get a null of about -33dB. Since they were exactly the same sine wave (with a slight delay), I was expecting DiffMaker to give me pretty much -infinity.
Loaded the two files in and let 'er rip. It took just about forever to do this nulling operation on 2.5 seconds of audio on my lightning speed computer. That would be sarcasm, well, it did take forever (I have a slow computer). It gives nice status reports along the way, plenty of FFTs done, caluculations, matching, whatnot. Started using up a bunch of memory. Then it was done. I listened to the difference file, and it sounded just like the reference and/or the compare. I loaded the DiffMaker created file into my audio editor and found that the sine wave was now -9.8dB. In other words, the difference was even greater than the reference or the compare file.
I read the help files to find out what I was doing wrong, but got nuthin'. I'll keep at it for a while. In my opinion, if something doesn't work for a simple test case, there's no way I would trust it for use with complex signals. As of this moment, I'm not impressed.
