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Exporting a bach.roll

Hello Everybody,

For my Orchidea patch Max project, I was confronted with the object bach.roll … Using the bach package. Ok, it’s not OM but there’s a message : “exportom” for the bach.roll so it’s appropriate.

When you send “exportom”, bach.roll saves a message that looks like Common Lisp but is not. The brackets should be replaced with parenthesis.

You get this file, for example.

From-Bach.txt (2,2 Mo)

To integrate it into OM, you have to use a multi-seq and select “From bach” with right-click :


In this solution, you will see that each stave of the MULTI-SEQ has 22 staves, there are 22 instruments in orchidea.

From-bach.omp (261,1 Ko)

But also 22 channels… and then OM glitches. Which is normal… Beyond 16 channels, It’s darkness. PortMidi needs to have a SimpleSynth on 2 channels to stop generating messages about the ports… But there are also unwanted sounds, which look like bad General Midi percussions. The redirection proposed in the MIDI preferences doesn’t seem to work, or at least badly. I don’t hear any difference.


On the other hand, it is possible to do something with R-udp-player

I could dig “Bach.roll” I’m sure that I can find a way to fix that, but as I don’t find the result useful, musically. I won’t. But I wanted to share this experience.

Keep safe,


Ps : image force to use 2 ports but same sound

Hi Jérôme,

That seems weird to me, I never have to edit bach exports to OpenMusic. I don’t get any square brackets in my bach exports when I use the exportom message.

Here’s an example of bach export — you can import it directly into a Multi-Seq in OM:
exportom.txt (13.7 KB)

You could perhaps try using a bach.score instead, and export with the exportxml message to OM.

All the best,

Hi Antonio,

So it’s brackets for bach.roll and parenthesis for bach.score ?

Weird, thank you, i’ll go and see, but the real problem is the number of channels in this experience.

But the results is not very musical, but I will see for other use




I’ve attached an example of a Max patch for Orchidea (0.5) that exports to OM and MusicXML, which I used to produce the bach export in my previous reply. See if it works for you, and adapt it to your needs.

Here’s the Max patch:Orchidea XML Export.maxpat (43.6 KB)

Hope this helps.

All the best,

well I just tried your patch :slight_smile:

test.txt (16,2 Ko)

from the bach.score. …… square brackets !

We need a time signature, a tempo, and the score without the sound is meanless with Orchidea. Orchidea has its own sound management.

So, square brackets… Weird indeed. My guess would be that it must be that the bach versions aren’t the same… I’m on bach v0.8.0.1b.

All the best,

"name" : "bach",
"displayname" : "",
"version" : "0.8.1",
"author" : "Andrea Agostini and Daniele Ghisi",

release from the package manager



this story of square brackets comes from Daniele, few days ago…



It’s an issue with the last bach release, I just checked the bach forum on this… And the good news is that Daniele says in a thread that the issue has been solved for the next bach release.

The thread is here: https://www.bachproject.net/forum/viewtopic.php?f=2&t=879

All the best,

thank you !

Actually MyOrch is my patch.



1 Like

Sorry guys,

Had to change your topic’s branch. This is related to Orchids-ea-bach-max, and not an openmusic issue.
It’s better to narrow your problem here.
If you need some expertise for OM’s editor structures please be free to ask.

and take care

Dear Karim,

Sorry for this stupid mistake…



Hi Antonio,

I’ve tested your patch and export the bach.score and I loose some ties in importation. (3 actually)

For memory : Orchidea XML Export.maxpat

And see the OM score objects in this patch. From-bach.omp

So for bach.roll : MULTI-SEQ and bach.score : POLY

I’ve embed this in MyOrch :


thank you for this info…

I will notify this to Daniele @ghisi

But the real subject is using fixed tempo and time signature, it’s a musical approach… It doesn’t fit to a lot of music… MyOrch is a tutorial, indeed, and I’m wondering how to improve it, knowing that there’s some people who has contacted me and do not know how to patch… Everything must stay intuitive, in order to focus to Orchidea…



PS : the problem with the channels which are overhead 16 is my real problem

Hi Jérôme,

Concerning the ties that you lose, I think you may be losing them before export… Every you time you change the temperament, just remember to quantize again after that.

Concerning rhythm and quantization in bach, I think you don’t need to worry too much, bach is quite powerful, and very OM-like and OM-friendly in its treatment of rhythm and quantization — check out bach tutorials 11 and 13, and adapt them to your needs for exports and MyOrch.

All the best,

HI Antonio,

Yes, it works well with bach.score to POLY, less for bach.roll to MULTI-SEQ… I can see in the bach.roll that there’s each channel for each stave…




Hi, everybody,

I substituted bach.roll for a bach.score in my patch.

Its export capabilities and the fact that importing bach.roll into OM poses a MIDi channels problem, make it better to use it, even if I wasn’t heading for that.

So with exportom, I get a file with square brackets, which will be fixed in the next bach version. Little trick, I add the .bach extension when I export from MyOrch. Previously, I linked this extension in the Finder with Sublime Text, my favorite text editor. It’s faster to do the substitution with parenthesis.

So I get a file like this :


In OM, I create a POLY, I import the .bach file


And that seems to be ok ! Thank you very much.

This allows us to run the orchestra the way Carmine wanted it, so the bach.roll is set on this one, but it’s just display. By the way, you can’t see it in the POLY. Enjoy the micro tonality.

Case solved,



PS : process