Sf2 MIDI base velocity incorrect after export

[gligeti]

Edited 2014-10-22 @tresf to add findings
I think I found what gets reset. The MIDI base velocity seems to be messed up or changed somehow with the change. This instrument has different sounds at different velocities, that's why it makes a huge difference.

Win 8.1 64 bit LMMS 1.0.3

Using Fluid R3 GM soundfont (http://www.musescore.org/download/fluid-soundfont.tar.gz) on Windows using default settings, select Calliope Lead. Add notes. Play. Notice how it plays in a low volume. Now use export and export the project to a wav file. Now the volume changes to a much higher volume (settings seemingly unchanged) both in the exported wav file, and in LMMS after the export.

[tresf]

Is there a chance it's grabbing the wrong bank in export? (Is there a bank which matches the volume level you are experiencing?) Also, is there a chance the export settings are contributing to the bug? I've used soundfonts heavily in 1.0.x versions without any major volume discrepancies so this bug may be specific to the soundfont you are using.

[gligeti]

I tried it with the default export settings as well as with oversampling. The weird thing is that after the export the volume is also changed when played inside LMMS not just in the wav (note that I suspect that in fact the original low volume is wrong, it is way too low, and somehow it gets corrected with/after the export). It may be some setting that gets reset that I am missing, but I don't see anything changed.

The issue is easily reproduced as I wrote it. It may be a bad font, but then I'd like to report it to them, although even then LMMS should behave deterministically.

[gligeti]

I think I found what gets reset. The MIDI base velocity seems to be messed up or changed somehow with the change. This instrument has different sounds at different velocities, that's why it makes a huge difference.

[diizy]

No one has asked the most important question yet:

Can anyone reproduce this on 1.1?

[Sti2nd]

I have had that bug before! HEY, that is the same sf2 file, then it is likely to be the sf2. It happened because I wanted to replicate a piece I made in Musescore, and so I downloaded the sf2 Musescore used. This was with 0.4.13

[tresf]

No one has asked the most important question yet:

Whoops... my mistake. I'll leave the 1.2 tag for now but it should be removed if this has gone away.

[gligeti]

Eeeer I am not quite ready to upgrade to the 1.1RC, but may try it on another rig with 1.1 later.It is quite easy to reproduce, if someone wants to try it, even if you just watch the levels it clearly is mouch louder after the export.
There is definitely something weird with the MIDI base velocity too which may or may not be related. If you load that soundfont, you'll see that the base velocity is set to 63, but not enabled. Enabling/disabling makes no difference. Now after working with the project eventually (several saves and exports) it got misteriously changed to 127, even though I never touched it -- but I can't reproduce that, not sure what caused it. (note that after the export, it still shows 63, still not enabled, but the sound is louder, and it seems that the velocity changed, not the volume)

[Sti2nd]

If we look at my experience and your experience and take it for granted it is the same bug, this has nothing to do with anything introduced after 0.4.13 (like the Midi base), and most likely, it is the sf2. I am going to try today in RC4, I think, downloaded the file yesterday.

[tresf]

I've confirmed on 1.1 that export ignores velocity settings on the SF2 instrument.

The title should probably be changed to reflect this. I don't see any other anomalies in playback or render related to the base velocity setting. For now, I recommend people reset the velocity to 67, turn it off and use the volume sliders/knobs to achieve this effect. If this doesn't yield the same sound, you may choose to record the sound device (rather than using export) which would be a workaround until this is fixed.

[tresf]

Also, saving these SF2 preset settings in a separate preset file doesn't help this bug, they're still ignored. I don't see any code in ProjectRenderer.cpp which could cause this. Perhaps the problem lies in sf2_player.cpp

[Sti2nd]

Reproduced here on LMMS RC4 64 bit Win. With the same sf2, though.

[gligeti]

Do you also reprocude the issue in RC4 that subsequent playbacks inside LMMS are also louder after the export, or does it only affect the volume of the exported wav?
Also, in 1.0.3 the green checkbox to enable the custom base velocity doesn't seem to affect things, it always gets applied.
Not sure if these are related issues or not.

[tresf]

No, the volume playback after render wasn't noticeably affected in my test
results.

[diizy]

On 10/24/2014 01:50 AM, Tres Finocchiaro wrote:

No, the volume playback after render wasn't noticeably affected in my test
results.

From a quick look, I can't see anything in the SF2 plugin itself which
could cause this issue. The fact that this doesn't happen (?) on other
single-stream plugins also maybe suggests some kind of bug in
Fluidsynth, but it's too early to say...

[tresf]

Very interesting... So I tried reproducing this on Ubuntu 12.04 x64, (stable-1.1 branch) and it seem the base velocity is honored. Is there a chance this is a Windows-only bug? (tested SDL and ALSA)

[tresf]

@pgiblock @tobydox any quick hints as to where to look if this export behavior is differerent between Win32 and *nix? I know Toby has a knack for tracking down the Windows anomalies and I believe Paul helped write the sf2 instrument.

[mikobuntu]

linux ubuntu 32bit { stable 1.1 } I can confirm the original bug, whereas after render the volume of said preset raises slightly. ( this is without touching sf2 base velocity )
I have looked at this soundfont in polyphone and noticed Calliope Lead has settings :- chorus 30% reverb 10% , so could it be possible that rendering a project is somehow switching these on, without any user interaction from the gui?

EDIT I'm almost sure that chorus and reverb are being switched on during/after render as when i used the gui switches and turned on/off the volume went back to its original lower volume!! @tresf @diizy

I did a further test by saving an .mmp both before and after render, but running diff showed the files where identicle.

Possibly unrelated, but worth mentioning....... that sf2 player spews out a lot of errors on load::_

fluidsynth: warning: No preset found on channel 0 [bank=0 prog=0]

** (lmms:3197): CRITICAL **: fluid_synth_sfont_unref: assertion `sfont_info != NULL' failed
fluidsynth: warning: No preset found on channel 1 [bank=0 prog=0]

this is a recursive error, which has been about for some time now , but imo it is non fatal?

[gligeti]

I know that the mmp file doesn't save the messed up state as if I save it after the render changed the volume, and reload it, the volume is back to the lower value.
Does the base velocity work for you as intended? As I said turning it on/off (the green on/off checkbox) doesn't seem to affect it -- it is always gets applied for me in 1.0.3 under w8.1 x64.

[mikobuntu]

@gligeti Oh yes i see what you mean, yes for example if i turn on the base volume, raise it turn it off again the higher volume will stay until changed again. I'm unsure if this is intended behaviour, i'd expect not, but i believe these are possibly 2 separate issues, where rendering a project 1st caused you to notice the initial rise in volume caused by the chorus reverb being applied, then on further investigation you noticed the base velocity bug?

[mikobuntu]

I'm going to start a new bug report on my issue concerning sf2 player ;)

[gligeti]

You are right, it IS the chorus that gets turned on (but not reflected on the led), and in fact I reproduced that if I toggle it on and off, the perceived volume goes back again. Good catch.

Yes, the base velocity is then probably a separate issue that I found by looking for what setting may have changed and found the odd behavior, but it sounded plausible that that gets messed up.

[tresf]

@diizy do you believe the velocity issue could be caused by this commit? 585f8b6

[tresf]

Can we get a confirmation that this bug still exists in stable-1.1 RC11? Namely Linux and Windows versions?

[Sti2nd]

Not by me, hard to reproduce and only with specific soundfonts I believe. I do think this

@diizy do you believe the velocity issue could be caused by this commit? 585f8b6

This is the way I remember the bug. It wasn't just pure amplifying of the signal, it was some chorus or effect causing it, it seemed.

[tresf]

Thanks @Sti2nd . I'd like to see if @mikobuntu or @Umcaruje can reproduce on Linux.

[tresf]

Closing since no one has been able to reproduce. Please reopen if you feel this was closed in error.

[badosu]

@tresf I've been out for a few days and noticed a lot of cleanup of stale issues, good work! 👍

[tresf]

The real thanks goes to these code contributors! 👍 Thanks for the gratitude though, it goes a long way. :)