Crossfade loops
Sometimes it's nice to have a smooth endless loop to mess around with. Right now the only iOS app I know of that can create a crossfade loop is Beatmaker2 strangely enough. So the workflow is record a chunk of sound with some synth app, import it into BM2, edit it with crossfade and trim the loop, save and export it to Loopy. I'm always looking for a more streamlined way that doesn't kill the creative urge. Or maybe I just learn to live with the harsh edges... Any better ideas at all?
Comments
Thanks for continuing to improve the app!
Anyway, Loopy pretty much assumes that your imported loops are already loops (i.e., designed to loop, without a seam), so it's best if you just configure your loop in advance.
Here's what I've found:
That first loop you sent to me is 1,065,920 frames long. I can open it up in the audio editing app Amadeus Pro on my mac, export as raw 16-bit PCM, and I can see all 1,065,920 samples, no problem.
When I open this file in Loopy (or in any other app that loads audio - I was testing using Apple's sample code, MixerHost), it can only see 1,065,165 frames - that's 755 frames, or 0.0171 seconds, short. Given that the seamless part is in those frames, it's no surprise we're hearing glitches at the loop boundary.
Now, if I re-save the audio out to another m4a file from Amadeus Pro, and load *that* - I see the full 1,065,920 frames being loaded in Loopy/etc, and there's no glitch.
So, the problem is with your file! Now, that's not to say there's not a bug in Apple's audio file loading code - perhaps your file is perfectly valid and legal, and Apple's code is messing it up. But it could also be possible that your file's not written properly, and it just happens that Amadeus Pro is more lenient towards weirdness.
What software did you use to create those files? It might be worth contacting the developer and letting them know there's something odd going on.