Hi.

I have built a step sequencer and I would like to record polyphonic notes into it. So far I figured out how to record monophonic notes into a table. But I am bit overwhelmed on how to do that if notes are polyphonic.
Does anyone knows how that would work?

@impression You will need multiple tables... arrays... one for each note.
Decide the maximum number of notes for the polyphony and use [poly] to keep track of note on/off.
https://forum.pdpatchrepo.info/topic/5311/polyphonic-voice-management-using-poly
You can use [clone] for the voices or build an abstraction, with each voice having its own array for the step sequencer, and either a master [metro] for timing or a "timeout" delay window set for moving on to the next chord. Because there is no such thing as a chord in midi...... just a serial string of notes arriving (nearly) at the same time.
You will need to pack the arrays with zeros for any voice that does not receive a note for its step.
David.

@impression The first step is to work out the data structure. If it's my project, I'd go with one of these approaches:

• Save MIDI note on and note off directly, without much analysis. Playback logic would then be very similar to MIDI polyphonic playback.
• Or, use note-off to calculate the sustain duration of the preceding note that matches the note-off pitch. It's harder to calculate that, but then you get a list of notes with parameters "note number, velocity, sustain duration" -- may be more useful for algorithmically manipulating the notes.

What are your thoughts about how to play back the sequence?

hjh

Thanks a lot for both of your help. It sounds much harder than I expected
Lets say I want 32 polyphony, that would be an insane effort. Even I don`t always use 32 voices, I thought I can keep it more dynamic, depending on how many voices I am playing
The link is very helpful though. Will need to make my way through it.

@impression said:

Lets say I want 32 polyphony, that would be an insane effort.

IMO this all comes down to data structure design. A bad design will require insane effort. A good design will scale up to any amount of polyphony you need.

What's the input? From your MIDI keyboard?

What do you need to do with the notes afterward? Just spit the MIDI events back out, or quantize them, etc etc?

[text sequence] is a nice way to store note sequences. Each entry starts with the time delta before this note, followed by the note data, which may be anything you want (e.g., note number, sustain time, velocity, suitable for [makenote] when playing back).

It would really help if you could explain the goal, to help design a way to un-insane the insane effort.

hjh

There is the bop project https://github.com/zealtv/bop (see bop.semisteps and bop.frets objects) that use decimals in a float to describe chords as intervals on top of the fundamental. Not so simple but very clever.

you can just put note on and stack thenm up on the same table. you would maybe use more than one array point for the information on each trigger point etc. and then read the table back at the correct speed with multiple points from the table at the same time.