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So thanks to Interlibrary Loan, I've been finally able to grab a lot (but not all) of the Zappa CD variations I'm intrigued by. In at least one case, though, I've encountered a strange phenomenon. To wit:

(waveforms left to the imagination)

The previous images were of a line-up I'm doing of the song "Joe's Garage" from the album of the same name. I recently determined that the "purple-face" old Ryko edition was more or less the same as the current stock CD. Surprisingly, however, the EMI edition--which I had previously assumed was very, very different--turns out to be from the exact same digital master (now, of course, I'm itching to see whether this is true in some other cases).

Here's the thing, though. They sync fine, and when normalized they do cancel out...kinda. The second image shows what happens when I run the null filter. Some parts cancel out entirely, while others don't...little blips don't cancel. This also happened on Broadway hte Hard Way and on parts of Mothers of Prevention and Grand Wazoo.

So what's going on here? Is this indicative of someone applying EQ to small sections of a track, or what?

-D

Xenu,
what software was used to do the null test?

That's Audition. Or Cool Edit Pro. Same thing (I have both installed).

This happens on a few other Zappa discs as well. Stuff stays in sync, but little bits don't cancel out, so it isn't sample shift or anything.

The Y-axis scale is calibrated in # of samples (smpl), 1000/unit?

Oh, that must be CEP, as I didn't change the Y-axis to DB. I'm not entirely sure what that's supposed to be, actually.

Geez, Luke. If you're going to delete posts, you should at least let us know in advance.

Nahh.

That is one large-ass .wav pic, you have to admit, X.

Sorry, sorry, I forgot to resize it. Jeez.

If you like I can stick it up on one of my website, and you can link to it here -- but only if you resize it a little.