Interesting, thanks for your feedback!
It occurred to me how to work around this high speed requirement. Thought I’d share in case you’re interested.
There’s a lot of work to do to run a full beat detection algorithm in the time for one audio sample (or less, since the “end loop” click could come any time in a sample period, but let’s pretend the button is synced to the sample clock). So much work, that it seems really unlikely it could be done fast enough to make auto quantise work.
However, the option that I thought of is that you could spread some of the work during the loop recording phase. If you ran a low priority task that spread over N samples, you could already have done a lot of auto correlation of the loop as it’s being recorded. That would give you a secondary list of potential BPM values ready for when the loop closes. When it does close you can compare the potential list from the loop length with the potential list from the auto correlation. That should let you pick the appropriate BPM quickly and with more confidence.
Taking that further, you can rule out impractical BPM values early on. Let’s say the fastest possible is a very generous 400 BPM. That means you can expect at least 150ms per beat. So you can pick an algorithm that takes that long because you know that if the loop closes sooner than that it was less than a beat and so insufficient for analysis. Then add in that you probably also are going to require that the time signature be set, it’s not unreasonable to require at least one measure of beats to do best detection, so you would have 300ms (in 2/4 at 400bpm) at least to do some pre calculations.
Appreciate this! I’ll forward your thoughts, thank you as always
Brennan, could you provide an update on Auto-Quantize? (I have updated to 4.1.5, but I don’t see it in the manual.)
To be sure I’m using the correct name for what I want, I am looking to be able to record my first loop and then have Aeros use the length of that first loop to set the BPM (particularly, midi clock out to an external drum machine).
I believe that’s what I’m seeing Reinhardt Buhr and other YouTubers do with an RC-505.
This is not yet doable on the Aeros but both AutoQuantize and MIDI Master are in progress and we will soon decide in what order we release them, they are tied in many ways so it depends on the developers.
We have just released the beta for 4.2.x for Fade in/out, Reverse, and Multi-language support, so we are on the path to the behavior you are talking about.
Check out the feature request for AutoQuantize here.
Thanks for the question, stay tuned we are not far off now!
I’m not quite sure what auto quantize is but I only use free form (no beat buddy) and Aeros seems to detect measures just fine. This works for me with or without locked tracks.
AutoQuantize would essentially create a quantized song out of a freeform song, giving it a BPM and a time signature. Pairing this with MIDI Master capabilities you could have the BeatBuddy follow the Aeros after you come up with a random idea with no specific tempo. This is all theoretical right now but like I said, it is in progress!
Thanks for the question