Issue - Export does not contain all notes

[obitwrite]

Hydrogen version * : 1.0 / 1.24
Operating system + version : macOS, multiple versions
Audio driver + version : Core Audio, multiple versions

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I've recently started using Hydrogen again. It's great and easy to work with. However there is one issue that I can't seem to understand.

Whenever I export a song that has a pattern with more than 3 things at the same time (for example, kick, hihat closed, hihat open) it seems to choose only 2 of those things to include in the export. I'm exporting to separate tracks.

I've:

• Tried making multiple patterns, where each pattern has only one thing in it. But the result is the same when exporting as a song. Whenever 3 things are played at the same time in the pattern, it seems 1 thing is missing in the separate export files.
• Tried using multiple drumkits (both built-in and downloaded), and the result is the same.
• Tried different audio formats: WAV and FLAC.
• Played around with polyphony settings, no results.
• Searched the manual and other issues on Github, but couldn't find an answer.

Am I missing something here? Or could this be a bug?

[theGreatWhiteShark]

Hey @obitwrite ,

Am I missing something here?

That could be caused by a feature called Mute Group. At least I did just ran right into it and thought I could reproduce your issue at first.

E.g. the AVLDrumkits-BlackPearl-2023 puts all its hats in one mute group, all its crashs into another, and most of its rides into a third. So, when triggering to hats at the same time, only one of it will make a sound.

Could this cause your issue?

[obitwrite]

Thanks @theGreatWhiteShark for pointing me in the right direction. Mute Groups is what I should be looking at, and this of course makes complete sense.

I was coming from Hydrogen 1.0 and mostly used the TR808EmulationKit, but for some reason exports from that kit also always resulted in simultaneous hats getting muted. But it could have been something that I accidentely switched on after years of use.

For anyone reading this after a search. If your Hydrogen export with separate tracks is missing notes, check the Mute Groups setting in the Instrument Editor. And also: it makes sense that the notes are missing, only turn off Mute Groups if – for example – you want to make sure all notes carry over when you import separate tracks in your DAW.

[obitwrite]

What still puzzles me, however. How does the Mute Group setting in the Instrument Editor relate to the setting in the drum kit itself? It seems that I can also assign my own Mute Groups in the Instrument Editor? And does this setting also show Mute Groups embedded in the drum kit, which I can then override?

Also, when I'm setting several Hihats (AVL Red Zeppelin 2023) to Mute Group 1, and then add some simultaneous notes (for example 3 at the same time), leave them out, add them in again in the pattern editor. I can end up with a situation that mutes notes randomly. So for example, on one note the Hat Semi is muted, on the other the Hat Pedal. Which notes are actually prioritized?

These experiences might not be related to a bug (let me know if they are), but perhaps have more to do with the (idea of) Mute Groups not being transparant. What notes are prioritized? How can I control it properly and consistently in the GUI? Just wanted to add these experiences.

[theGreatWhiteShark]

What still puzzles me, however. How does the Mute Group setting in the Instrument Editor relate to the setting in the drum kit itself? It seems that I can also assign my own Mute Groups in the Instrument Editor? And does this setting also show Mute Groups embedded in the drum kit, which I can then override?

You can think of drumkits in the Sound Library section as bundles of sample files and parameter settings. Whenever you load one drumkit into a song, the instruments in the song's current drumkit will use those sample files and the song's drumkit parameters are set to the ones provided by the drumkit. All changes you do from there on will solely live in your current song. In order to save them back to the drumkit (in the Sound Library) itself, you have to use the menu option Drumkit > Save (As).

Also, when I'm setting several Hihats (AVL Red Zeppelin 2023) to Mute Group 1, and then add some simultaneous notes (for example 3 at the same time), leave them out, add them in again in the pattern editor. I can end up with a situation that mutes notes randomly. So for example, on one note the Hat Semi is muted, on the other the Hat Pedal.

Good question. I haven't looked into this part of the code base yet.

Hydrogen is almost about 25 years old and has seen a number of new features over the years. Early features, probably like this mute group one, sometimes didn't get a refresh when a new one was affecting them. So, thank's for pointing it out! I never used mute groups myself.

Which notes are actually prioritized?

I think this is up to us and I would doubt that there is already a consistent way to determine the priority (as you reported).

I would like the user to be in control of the priority but I do not want to introduce another widget either. However, the user can already rearrange the order of the instruments. When activating many patterns in a single row of the song editor we're already facing the question to which pattern recorded notes will be added. Our rule is: always to the bottom-most. I would reuse this pattern for the mute groups too in order to make the overall UX consistent: if there are several simultaneous notes of instruments of the same mute group, the bottom-most wins.

But we have yet another problem: there can be multiple patterns played back at once with each of them having several simultaneous notes within the same mute group. Here I would do the same: the bottom-most instrument in the bottom-most pattern wins. It sounds very complex and very difficult to find out why none of the notes in the top-most pattern are played back, but I think we can neatly handle this with the idea in #53. After all, we already render notes from other playing patterns as background notes.

[obitwrite]

I see, so the Mute Group setting is embedded in the drumkit as a default setting. And can be editted afterwards. Loading the drumkit again fresh, makes you go back to the default Mute Group settings.

The bottom-most rule probably works. Because it fits how I use Hydrogen. Upper patterns are the backbone of the song. Patterns at the bottom are usually accents. To me, accents (for example open hat vs closed hat) should have the priority. But however you use it: bottom-most rule should work. Sounds great.