Support and discussion for all of Akai’s modern standalone MPCs including the MPC X / X SE, MPC Live 1, 2 & 3, MPC One / One+, MPC Key 37/61.
By sserpell Thu Mar 21, 2019 8:52 pm
Hi
I've been using my Tubesynth a lot, for pads, pluck sounds, etc, etc. So, I made a bass patch, I recorded a sequence and now after I played back it doesn't play all the notes, and when I want to play it thru a midi keyboard I here the first note and then theres just clicks in every key. These is happening in all the songs where I used these bass patch, so I went to the setup page in the program mode and changed polyphony to 2 notes instead of legato. Everything cool till more than two notes plays together, changed polyphony to 3 notes, everything cool till more than 3 notes plays together, then changed to 4 notes and I can finally hear all my sequence....
These happened many times and most of the time after I reset my mpc everything was ok
2.4 bug? whats going on?
By blackistone Fri Nov 13, 2020 6:45 pm
My version of likely the same issue:
I'm finding my MPC One doesn't handle legato correctly as well, specifically when playing the same note repeatedly. I first noticed this from the drone layer from my NDLR, which plays the same note in legato mode sequentially (until changed). If a new note is played, it's fine, but usually the notes come out as soft clicks, occasionally one will play normally, but only maybe ~5-10% of the time.

Debugging:
After a lot of having no idea, I noticed in the sequence editor, if you zoom in realllll close, and move one of the note's up or down the keyboard, one can see a very slight overlap, where the note-off comes right after the note-on. I assumed this was some issue with clock drift or something from the NDLR, from that got ruled out.
I then decided to do a very basic test: Draw a sequence of notes, and quantize using the internal legato mode (so not possible issue from the other hardware). It gives the same result

My current (entirely speculative) theory:
Whatever data structure the MPC uses for it's sequences records each note as a time(note-on) and a time(duration) rather than a standard sequence of midi events. If it stores this time information as a floating point, then there may be a rounding error when it re-interprets back into a normal midi play sequence. I think this because it still shows the notes as full length in the sequence editor, but only in playing does the out of order note-off become a thing.

Certainly open to any suggestions if anyone knows/has alternative proposals, and/or hopefully a fix.

This may also be the source of the legato issues in this thread: viewtopic.php?p=1768352 (beyond turning off legato in the synth as mentioned as the solution, there)