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Grandorgue Midi file format


New member
Hi everybody.

I have been using Grandorgue v0.3.1.1694 for a while and enjoy it everyday. I did some recordings in wave format whith excellent results.
BUT! I decided to record a piece in Midi format, in order to get more flexibility when editing (I am a poor player...).
The files are perfectly played back by GO.
The problem (big problem after 3 hours of recording...) is that the files seem to be impossible to use on the outside word:
- under Cubase, nothing is imported;
- the file is imported by Audacity, but not played (I see the notes, the playback doesn't start);
- the file is imported by Midi Editor, but it is played in one second;
- Hauptwerk can't play the file.

Question: can anybody tell me if is it necessary to adjust some parameters, and in this case where? Or GO Midi files are of the esoteric type, uncompatible with the outside world?

Thank you in advance for your answers.


New member
GO midi files contain:
* A few GO specifc sysex messages, which setup the MIDI event handling in GO [using the same sampleset, stop and swell actions are also played back]
* Notes are stored as normal 9x messages
* Stop changes, swell and other things are stored as NRPN messages.

If you sent the whole MIDI stream back to GO using the same sampleset, you will get the same sound output as during recording.
Your MIDI editor should preserve the channels, SYSEX and NRPN messages. Don't forget to play back the SYSEX messages, as they tell GO, which NRPN/9x note messages control which element.

Add audacity: As far as I know, its an audio tool (not MIDI).

Add MIDI editor:
GO creates MIDI files using the "frames per second" option for encoding the timing.
See offset 0x000Ch with a negativ value [0xE728]:

quint16 basisVelocity;
timePerQuarter = (int)basisVelocity;

So MIDI editor is probably missing code to handle a negative basisVelocity.

PS: GO wants a MIDI port to connect to. If you are using sequencer software, which tries to connect to GO, create a virtual MIDI port in between.


New member
About Midiocre

I use Midiocre for editing G O MIDI files - very handy for inserting stop on/off commands, never had any problems with playback.


Thank you for your quick answer.
Midiocre is a "developper type" program, as far as I can see.... It is interresting because it shows all Midi data in a rough way. But editing in a musical meaning of the word is not really possible with it.
As indicated in the following reply, the problem I encounter is related to time scale definitions. I have to check for a solution to easily exchange Midi files between GO and an editing software ...
Thanks again.


New member
Thank you for your quick answer.

I confirm that, sending back the recorded Midi file to GO produces the same sound output as during recording. Of course, I did some playbacks to check what I recorded (and what needed editing...).
I agree that the problems I encounter are related to time scale definiton, because Midiocre for instance plays the file very fast (unusable speed).
Engeneering choices in GO are strange, because it is so easy to exchange Midi files between other music programs like Hauptwerk or Pianotech for instance and usual editing programs like Cubase (I agree that Audacity doesn't handle Midi).
I will go on to find a practical solution because I want to record and edit some pieces from time to time. This topic may be of some interest for other people as well.

I imported the Midi file into Widi Able Midi Editor. Then I exported it. This file can be played back by Hauptwerk or Cubase and is played very fast, at an unusable speed, by GO.
So the question becomes: how can we control the time-scale of the exported Midi file (back and forth)?


New member
From your explanations, I would guess, that Widi Able Midi Editor also doesn't fully implement the MIDI SMF specification. Its reads the file using an incorrect speed and will save "correctly" the incorrectly loaded timing using the other tempo storage format.


New member
From your explanations, I would guess, that Widi Able Midi Editor also doesn't fully implement the MIDI SMF specification. Its reads the file using an incorrect speed and will save "correctly" the incorrectly loaded timing using the other tempo storage format.

You are probably right! I left the investigations around Midi editing aside for the time being but I go on recording Midi data that take very few room on the ssd. Then I record as wave with GO the correctly played sequences and edit them with Audacity. This procedure also allows for chosing alternative stops associations and even to try other sample sets.


I've not done any MIDI editing recently, got involved in some video work, plus now got a couple of crashed PCs I'm trying to recover and using a laptop meanwhile.