I've noticed recently that effect 24(dj looper or whatever) shaves the highs off the sample.

Is this common knowledge and I just noticed?

I think vinyl sim does the same, and tape echo as well.

DJ Looper is just the digital delay with special settings for what you hear and how long the delay goes. As far as I konw, the way it works is there's slightly less bandwidth for delays than actual sampling, so the quality will go down a little bit with each repeat just a tad. Usually the first things to go are the high definition stuff hidden in the high frequencies.

BTW, you can use this same principle in semi-modular environments on computer (like Reason for instance) to create the same DJ looper effect using delay lines hooked up to a combinator.

Thanks for the info. It makes sense that the bandwidth is shrunk a bit. I never contemplated it. Doesn't bug me, I was curious. Thanks again.