ADSR 0-127 midi to time relation?

[casequickdraw]

Hi, I'm currently writing a plugin for a 3d package that imports midi data and converts note on/off and controller data to key frames.
I'm now at the stage where I have all the midi data in my 3d package, and i'm trying to create ADSR envelopes that are triggered with the note on ( attack, deacy, sustain) and off (release) messages, using the 0-127 midi data sored in the controller data for each A D S R controller.

I guess my questions are:

with Attack Decay & Release, are the steps 0-127 an exact measurement of time? or...

are the steps 0-127 a time measurement that changes based on the midi clock BPM?

and are these steps the same on all synths/samplers?
or are they different on each unit / piece of software?

any help on this topic would be greatly appreciated, even a point in the right direction would help
I have searched the far corners of the web 4 an answer 2 this question, but 2 no avail.

[johnbowen]

The values displayed are completely meaningless in terms of time values. Unless the synth's display has things labeled as seconds, milleseconds (ms) etc., you cannot tell what a value from 1-127 means - it's just a reference number. Each individual synth designer can decide on a taper (or curve) for the knob and display settings, so there's really no standardising of it possible.

Hope this is helpful,
cheers,
john bowen

<font size=-1>[ This Message was edited by: johnbowen on 2005-09-13 23:35 ]</font>

[alfonso]

If you stick a little with the mouse not pressed on an envelope fader, a popup will come out with msec. value.