WAV file tools, specifically a compare

[newlifedrama]

I've been looking for a tool to compare wave files (intelligently). I only found one but it doesn't work on WIndows 7. So I am writing my own in C++. Is there an Internet forum to discuss topics like this? Here's what I am doing with it.

Basically I want to test out recording quality. I had trouble transferring music tracks from a SONY MD system into my computer because sometimes I heard "clicks" in the transferred file. I think it had to do with the two digital clocks not being sync'd or dropping sync. So I want to make two recordings and compare. I want the pgm to tell me how identical they are numerically (100% would be every digital sample is identical), and also produce a subtract of the two files so I can hear/see where the glitches are. Obviously you have to align the two files up, i.e. skip leading silence and match up the starting positions. I am doing this by convoling the two files for about 1 second of sound, and then shift the files 1 sample in each direction for about 20,000 samples, and find the maximum value. This is where the two files are most similar.

Anyway, if I compare multiple recordings and they are different, I should be able to spot issues. If they are the same, then I am pretty confident there are no glitches in either recording. I also want to test out a pure digital transfer - from one computer to another thru USB sound boxes that are hooked up digitally. Theoretically there should be no loss at all. Once I verify this then I can try the analogue path and see how poorly it performs. And also test out the analog line-in jack on my computer. Ditto for the analog line out on the USB box, and the computer. So I can see if I am getting my money's worth from the external box. By comparing new files to the original WAV file, I can get a good indication of the quality of the computer's sound system and the USB sound box (I use Focusrite Scarlett 8i6). I also plan on having the program re-compute the two tracks' alignment every second, to see of the recordings have any time skew in them, and convert this to a wave file for viewing the results (in a pgm like Audacity or Reason).

I figure a program like this (it's a command shell pgm now) would be useful to other people, seeing as how I couldn't find anything out there. It seems most useful to test out the quality of recording and playback software and hardware. It will be interesting to see if programs like SCS, Reason, Audacity can all playback a WAV file identically through a digital output. And whether Reason and Audacity can record without any loss through a digital input.

Let me know if you know of any similar tools, or how useful you think such a tool would be. Or if there are forums, websites, where this kind of thing is discussed (I'm sure there are, I just haven't looked).

[Eric Snodgrass]

I know Adobe Audition definitely has the capacity to compare .wav files via samples per file, but it is fairly expensive. Try the demo for free.

Wavelab will most likely also do what you need it to do. There appears to be a full version and Wavelab Elements, which is probably a "lite" version.

I'm sure that something from Izotope will do exactly what you seek.

For the more inexpensive stuff:
Have you tried Reaper? It might do what you seek.

You might also take a look at Goldwave. I've not used it myself but I've read some posts from folks who like it. It's very inexpensive.

Most, if not all, of the above have free demos you can download.

[newlifedrama]

Thanks for all the pointers! I've heard Audition has comparisons - a friend has a license so I'll try that out. I looked briefly at the other tools and didn't see anything obvious. They look similar to Reason, allow you to mix, process, analyze lots of tracks. Comparing just 2 tracks seems to be a hard feature to find, even if the tool has it - it probably requires lots of searching in the manuals. But I'll continue to investigate. Just a simple compare isn't terribly useful, it really has to align the tracks and report good statistics about how similar they are.

This isn't terribly useful to SCS users, unless you are either recording your tracks and want to test out the quality of the recording path, or if you want to test out the quality of your playback path. I am very curious how good the onboard line in/out audio quality is on a laptop or deskside computer. My USB box only has 4 ananlog outputs, 2 SPDIF. I am wondering if I can use the line-out headphone jack to get another 2 , and if I do what is the quality? I know it sounds pretty good, but am looking for an objective measurement. I hope to use my program for this purpose.

[Eric Snodgrass]

A program to do specifically what you want and only that is probably something you will have to create, considering it is only a one-trick pony, and once it is done with that one trick then the program is just taking up space on your computer.