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Understanding envelop time quick edits

Understanding envelop time quick edits

2013-12-13 by <ricard2010@...>

There's something I've been wondering about for a while: When editing envelope time parameters, such as attack or decay, a value of 0 means 'instantaneous', whereas higher values result in longer times.

However, when setting up a patchcord in order to map a MIDI controller (i.e. quick edit knob) to an envelope time, the resulting 'amount' value is normally set to a negative number. This results in a knob position of far left giving a corresponding time of 0, and advancing the knob results in longer times, as would be expected. What I don't understand is why the patchcord amount in this case must be set to a negative number; that would tend to shorten the corresponding time parameter rather than lengthen it I would have thought.

Is there any explanation for this?

/Ricard

Re: Understanding envelop time quick edits

2013-12-13 by steve_the_composer

This is interesting. I never played with this systematically before. I seemed to duplicate your results. My gut inclination was to say its coded as an inverse relationship.  But That didn't feel right, so I started playing with level.

Here's what I have right now (using a riff to hear what's going on):

MidiE -> VEnvAtk + 022 [I also tried other values]
Attack1 26 9%

When MidiE knob is down full (counter clockwise) which I would assume is 0, the short attacks are very short.As I turn MidiE clockwise, the attack seems to take longer. 

At Attack1 26 0%, MidiE has no effect. Leaving MidiE up full, changing the level from 0% to 100% has no effect. However, with the level at 100%, lowering MidiE seems to make the attack take longer.

After a long day, my brain is not at its peak, but clearly level is part of the equation, too. I am not sure what all this means, and I realize it doesn't explain what's going on, but I thought as long as I played around, I'd share my results and maybe it will help to find an explanation.

Steve








--- In xl7@yahoogroups.com, <ricard2010@...> wrote:
Show quoted textHide quoted text
>
> There's something I've been wondering about for a while: When editing envelope time parameters, such as attack or decay, a value of 0 means 'instantaneous', whereas higher values result in longer times.
> 
> However, when setting up a patchcord in order to map a MIDI controller (i.e. quick edit knob) to an envelope time, the resulting 'amount' value is normally set to a negative number. This results in a knob position of far left giving a corresponding time of 0, and advancing the knob results in longer times, as would be expected. What I don't understand is why the patchcord amount in this case must be set to a negative number; that would tend to shorten the corresponding time parameter rather than lengthen it I would have thought.
> 
> Is there any explanation for this?
> 
> /Ricard
>

Re: Understanding envelop time quick edits

2013-12-13 by steve_the_composer

More testing (Switched to Q Bass ROM Instrument on one of my ROMS to really hear the attack):

MidiE -> VEnvAtk -022 [negative numbers = inverse] 
Attack1 7 0%

Turning MidiE from 0 to 127 (clockwise), the attack time gets longer.



MidiE -> VEnvAtk  +068 
Attack1 112 1%

Turning MidiE from 0 to 127 (clockwise), the attack time gets shorter.


Conclusion:
Its counter intuitive (i.e., backwards).

Steve

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