xewton.com

Feature
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One should be able to create and name a track which could have any set of notes or MIDI track. Then when using the drumpad where we play chords , we should be able to add the named track as a pad.

Along with chords when we touch this pad it should immediately play the track without any delay.

That's a good idea, but I'm afraid I can't add it to the list because it would require us to rewrite large parts of Music Studio. It's built around the idea of 1 sequencer that plays all the tracks and 1 selected track where keys and pads trigger 1 instrument. Rewriting it so that a pads can trigger tracks would mean rewriting the sequencer from scratch, which is not feasible considering our busy schedule for the next years.

What’s the longest audio file that can be loaded into a drum kit instrument?

There is no limit, as long as the instrument doesn't take up more than 80% of the available memory (RAM).
I see where you're going with this, one could export all tracks separately to WAV files, create a user instrument that maps each wav file on a key and play it on the drum pads -> Eureka