Internal sequence playback behaviour when DAW(Reaper) playback looped.

[mikej01]

Reaper 7.42
macOS Sequoia 15.6
vmpc2000xl 0.9.0.4

(Note: This is not a high priority issue for me).

Hopefully I can explain this one so it makes sense. I'm also not sure if this behaviour is particular to Reaper DAW.

With a 2 bar length sequence programmed in the internal sequencer -

Would the expected behaviour be for the internal sequence to play back and loop (with sequence loop set to on in plugin) as long as the DAW is playing, independent of the DAW playback loop setting?

What I'm finding is that if the DAW playback loop is set to one bar or less from DAW timeline 0, the plugin will only play those measures from the start the sequence once, and not repeat. Eg for a 1 to 4 (1 bar) measure loop the plugin will play measure [1-4] then stop.

Some more examples:

If the DAW loop is set to more than 1 bar (eg 1 bar 1 measure), then the plugin will loop the current 2 bar sequence in it's entirety.

Creating a [1-3] measure loop in the DAW from measure 1 results in the plugin playing measure [1-3] then stopping and not looping. Creating a 1 bar loop from measure 1 results in the plugin looping the current 2 bar sequence.

Creating a 1 measure loop in the DAW from measure 2 results in the plugin playing the first 2 measures then stopping.

Creating a 2 measure loop in the DAW from measure 2 results in the plugin playing the first 3 measures then stopping. Creating a 3[+] measure loop from measure 2 results in the plugin looping the current 2 bar sequence.

• This is all with an empty track in the DAW.

[izzyreal]

You're certainly on to something. No thought has gone yet into how to sync VMPC2000XL to its host in terms of musical position, and there are certainly opportunities in this area.

Before we continue our discussion -- it seems you have conflated "measure" with another concept. I suspect you have conflated it with "beat". As far as I know, "bar" and "measure" are different words for the exact same thing.

[mikej01]

Before we continue our discussion -- it seems you have conflated "measure" with another concept. I suspect you have conflated it with "beat". As far as I know, "bar" and "measure" are different words for the exact same thing.

Yes, you are correct I do mean "beat".

You're certainly on to something. No thought has gone yet into how to sync VMPC2000XL to its host in terms of musical position, and there are certainly opportunities in this area.

Not sure if this is of any help?

Philosophically, perhaps the correct answer would be to do whatever the MPC does? I thought about this after making the request to continually sync to the DAW tempo.

Practically, I think the options are broadly (assuming timing is sync'd) is to sync from the play start point, or sync with the (absolute?) MIDI song position pointer. I think there might be some settings for this already? I will have to check.

Working in the DAW I think the use cases would be:

• Looping a 2 bar sequence in the plugin to jam along with in the DAW, and just make sure the start bar is set correctly in the DAW, before pressing the DAW play button.
• Don't use internal sequences, and program the MIDI in the DAW.
• Program the sequences in the plugin and trigger them via midi using the 'Next Sequence' feature in pad mode.

Setting the MPC to the first sequence, then triggering the next sequence via midi in the last beat of the previous bar worked well when I tested it briefly. I think you can trigger a maximum of 64 sequences. You have to start the DAW at the start of the right bar to keep the bars in sync, and also you might have to wait for the DAW playhead to go over the next sequence MIDI note to trigger the correct sequence. Doesn't quite work if you start the DAW half way through a bar for example. I think there is an immediate mode in the plugin that might start the sequence as soon as the pad or midi note is received, I need to spend a bit more time with it.

• Sync with the MIDI song position pointer for VMPC song mode. Might mean you have to put an empty sequence or two at the start of the song.
• Programming a sequence or song in the plugin, play it through and record the plugin audio out to the DAW.

I think you might be able to offset the song position pointer in the case you are in sequence mode. So if you start the DAW halfway through a bar, the plugin also starts the sequence half way through the bar. Sonic Charge Microtonic works like this.

Regarding MIDI -

MPC Beats, and Sonic Charge Microtonic also have a feature that allows you to 'drag and drop' the internal midi sequence for arranging in the DAW.

I think in the plugin you could already perhaps record the MIDI sequence data to the DAW by setting the track to MIDI output (rather than DRUM1-4).

Because VMPC uses an Akai format for saving programs and sequences, it is also possible to load VMPC programs and sequences in to MPC Beats. So it is currently possible to use the MPC Beats drag and drop feature to export the midi.

[izzyreal]

I'm not very opinionated at the moment, so I'm happy to experiment with most, if not all, of what you've mentioned. To keep things manageable I suggest to limit the scope to the below 2 items for the moment:

1. Sync VMPC2000XL's musical position to the DAW's right before starting to play. This way, if the DAW is at beat 2, VMPC2000XL would also start playing at beat 2, etc.

2. VMPC2000XL shouldn't stop playing if the host is looping.

What do you think? If you agree, I will raise reparate issues for these 2 improvements.

[mikej01]

Agreed. I feel this would be the ideal behaviour.

[izzyreal]

Here's the first breakout issue: izzyreal/mpc#264