Sustain problems (VMS 2.12.4) ?

Hi,

1. First and foremost: Sliphead is/was an MT-32 game, its soundtrack was originally composed for the MT-32. The GM conversion you use for listening is just a rather weak afterthought. If you really like listening to Midi files as you have written then you should re-download the MT-32 version of the Midi file and listen to it instead. If you do not have a real MT-32 you can use Munt as a Midi out port or you can use my Munt Vsti plugin. This is how Sliphead was intended to sound by the authors:

https://youtu.be/sgWWWfIvgjc

2. The converted GM file you use contains GS specific decay time (CC# 75) controller messages that a GM file should not use. They are most likely left there accidentally. Newer Bassmidi versions (that VMS use) implements these controllers while most other SF2 soft synths do not. Together with SF2 soundfonts that listen to decay time changes this can result in the effect you have described above. I have uploaded a fixed version of your GM Sliphead Midi file that does not contain these CC#75 messages anymore so does not have your described side effects:

  Bye.

Hi,

Marvelous, perfect answer :-)

My first intention was to compare the original MT32 version (using Munt) with the alternate (GM, GS, XG) versions that was shipped with various Sierra games using several soundfonts.

During this comparison I noticed the problem. Your fixed GM version sound now very similar to the Timidity version. Thanks !

Now I have some other questions:

- why are not all soundfonts affected by this leftover message ?

- how are computed the effects associated to a soundfont intrument and a controller messages (do one have priority ? do they sum ?)

- how do I check for incorrect controller messages ?

- how do I get rid of them ?

Many thanks again for your help and explanations.

1. It's because every soundfont defines its instruments/presets differently. All soundfonts are affected by these controller messages but the effect differs depending on the instrument attack/decay time definition. The problem manifests itself more on bass-like instruments where the decay time is usually shorter from the beginning and it seems were not tested well with 0 (zero) decay time that your original Midi file uses.

You can test the behavior with my Midi player. First download it:

https://falcosoft.hu/softwares.html#midiplayer

Then you should change the controller number of "User" controller knob to 75. Then select an instrument (like Picked Bass or Synth Bass 2) and change the knob's value to 0 (zero). Then play some notes on the virtual piano and listen to how these instruments behave with different soundfonts (soundfonts can be selected in the device settings dialog of the player after you enabled Bass/Vsti mode in the dialog). But you can also use VMS as standard Midi out port if you do not enable Bass/VSTi mode. My player's internal Bass mode use the same Bassmidi library as VMS so it should sound the same.

2. It entirely depends on the soft synth engine how controllers are implemented (if at all).  If you are interested in the details you should ask Ian at un4seen.com forum (Bassmidi's home).

3. You can also use my Midi player to find and delete such problematic controller messages. Open the Event viewer/Debugger dialog at the right hand side of the player after you have loaded your Midi file from the playlist. Then set filters to "All Controllers'. You can inspect the different tracks by adjusting the "tracknum' up/down control. By pressing F3 you can select the next controller. Look for controller's with a 'Byte 1' value of 75/named 'Decay Time'. You can delete them one by one or you can also use the batch delete option (Range of channel events). The changes are reflected immediately so you do not have to save them to file. Just rewind the loaded Midi.
Of course you can also use your sequencer/DAW if it has (most have) a Midi event viewer/editor.

If you press the 'Stop' button on VSTi plugin's control dialog you are automatically using Bassmidi (if you have already set a soundfont). Pressing 'Play' button on the VSTi's dialog loads Munt Vsti again. This is a very fast way to switch between soundfont and Munt Vsti. Do not forget to save the settings of Munt to a an .fxb file and also select 'Autoload Last used settings File' option.