Confused about volume drops in notes

[geckon]

Hi there,

I'm trying to remaster an old chiptune track with OpenMPT and I've used VSTis for instruments, but I'm struggling with volume.

To show what I mean, here is a link showing the volume change of the original track: http://i.imgur.com/hysyMbL.gif

And here is a link showing the volume change of my VSTi: http://i.imgur.com/ukieyXK.gif

You could see that the volume in my VSTi drops much more quickly than the original track. I tried delaying the decay and using the MIDI CC64 (sustain) effect, but that makes notes play simultaneously (I'd like to play one note at a time; the note cut/fade command doesn't stop the sustain of the previous note either).

I also tried using a compressor VST effect, but I couldn't find that much information about chaining the VSTi with the compressor VST (I loaded the compressor into the same channel the VSTi plays in, but that didn't work perfectly.

Is there anything i can do to stop the volume dropping so quickly?

Thanks in advance! (I'm a bit of a noob to OpenMPT in general, so some patience would be nice...).

[Saga Musix]

Without knowing what the original sample looks like and what kind of data you send to the VSTi (or how the patch in the VSTi looks like - does it use an ADSR envelope, etc), we can only make guesses.
If this volume drop is achieved by applying volume changes, then a possible difference are volume laws; trackers traditionally use linear volume while VST plugins often interpret volume in a logarithmic way. So in a tracker, v64 -> v32 means "half as loud", but when sending these volume commands to a plugin, "half as loud" could also translate to v56.

[geckon]

Thanks for the quick reply!

The VST that I am using is the Roland Sound Canvas VA (I don't know the technical specifics of that) and the data in the audio only includes notes with the 62 volume command (there aren't any other volume commands in that audio).

[Saga Musix]

Well, in that case you have to find a way to somehow change the shape of the instrument's envelope (read the VSTi's manual), because a note on its own simply doesn't tell you how quickly or slowly an instrument should decay. Since the website says that a variety of parameters can be automated from the host, you can probably (hopefully) change the ADSR envelope of the instrument.

[geckon]

I did try playing with attack/decay/sustain rate, but those don't seem to do what I want (the overlapping I mentioned before), so I'll see if the manual has anything else that might be useful.

Thanks again for the advice!

[Saga Musix]

If you want to guarantee that there is only one note playing at a time and no overlaps, you can also try sending CC 126 (Mono Operation), in case that's not configurable from the GUI.