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Information about the Velocity Curves?

jg666

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Information about the Velocity Curves?
« on: October 15, 2017, 03:01:38 AM »
I've tried searching through all the forums and and in the manual and on the website but can't find any information regarding the velocity curves that are available. I can see that there's 8 options available but don't know what the different options give you. I tried changing them and playing but couldn't work out what the difference was between them.
DSI Prophet Rev2, DSI Pro 2, Moog Sub37, Korg Minilogue, Yamaha MOXF6, Yamaha MODX6, Yamaha Montage6

Re: Information about the Velocity Curves?
« Reply #1 on: October 15, 2017, 05:10:19 PM »
I've tried searching through all the forums and and in the manual and on the website but can't find any information regarding the velocity curves that are available. I can see that there's 8 options available but don't know what the different options give you. I tried changing them and playing but couldn't work out what the difference was between them.

+1 for this.

I have a Prophet 12 too which is also unbelievably vague about the responses of velocity curves.

Like you I can detect no audible change when altering the curves either in my Rev2 or Prophet 12.

It'd be nice for DSI to clarify what the differences between the curves is supposed to be.

Murphy

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Re: Information about the Velocity Curves?
« Reply #2 on: November 12, 2017, 05:20:16 PM »
Were you able to find out more about velocity curves? I was trying to sort out how to set the Rev2 into a simple note on and note off (no curveJ, but couldnít find any information on what the eight curves do. I can hear differences, but it would be good to see a graph.

Re: Information about the Velocity Curves?
« Reply #3 on: November 22, 2017, 11:14:59 AM »
Having same issue here. Without tinkering with the velocity settings under amplifier, filter and aux envelope, I cant tell how changes in global velocity is affecting anything, even when I'm creating a program from scratch.  :-\

shiihs

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Re: Information about the Velocity Curves?
« Reply #4 on: March 25, 2018, 02:16:49 PM »
I share the same curiosity about velocity curves and pressure curves.

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Razmo

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Re: Information about the Velocity Curves?
« Reply #5 on: August 19, 2018, 12:07:46 PM »
I'd like an answer to this as well... please DSI... could you offer some insight into this?... maybe some diagrams that show the curves, like other manufacturers usualy supply within their manuals.

Please make that info about the pressure curves as well... I simply cannot feel any difference to the pressure curves at all when I try the different ones.
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Re: Information about the Velocity Curves?
« Reply #6 on: August 19, 2018, 03:48:23 PM »
We can suppose that they are the usual ones ? Like, for the velocity, the first four being logarithmic ones (with a less pronounced curve at each step), the fifth a flat linear one, and the last four being inverse log with an increasing curve ?
But then again, DSI not wanting to conform to what other manufacturers do, might not have followed that logic ?
The manual doesn't give any indications as to what those curves are, most unfortunately.
 
And for the pressure, at page 61 in the manual it does states that the default setting (curve 1) provides a linear response, but that's all. Which supposes that the other ones are logarithmic ?
Who knows ? Maybe DSI themselves don't remember exactly what those curves are ? lol !

EDIT: I had a look at the Prophet 08 manual, in the hopes that it would indicate what those curves are, but alas not.
« Last Edit: August 19, 2018, 03:52:00 PM by AlainHubert »
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Razmo

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Re: Information about the Velocity Curves?
« Reply #7 on: August 20, 2018, 01:29:54 AM »
We can suppose that they are the usual ones ? Like, for the velocity, the first four being logarithmic ones (with a less pronounced curve at each step), the fifth a flat linear one, and the last four being inverse log with an increasing curve ?
But then again, DSI not wanting to conform to what other manufacturers do, might not have followed that logic ?
The manual doesn't give any indications as to what those curves are, most unfortunately.
 
And for the pressure, at page 61 in the manual it does states that the default setting (curve 1) provides a linear response, but that's all. Which supposes that the other ones are logarithmic ?
Who knows ? Maybe DSI themselves don't remember exactly what those curves are ? lol !

EDIT: I had a look at the Prophet 08 manual, in the hopes that it would indicate what those curves are, but alas not.

i do not want to assume anything here, i want DSI to describe them so that I'm certain about their curves, because i really do not have the ability to just hear the difference between them ... and if the difference is there, it's very subtle and so minimal that i simply cannot hear any useful difference... I wanted to find an upward logarithmic curve, so that i do not need to press so hard to get at the higher modulation amounts... I believe I could hear a tiny bit of difference between curve 1 and 4, but it was so insignificant it simply did not matter...
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shiihs

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Re: Information about the Velocity Curves?
« Reply #8 on: August 20, 2018, 02:11:14 AM »
i do not want to assume anything here, i want DSI to describe them so that I'm certain about their curves, because i really do not have the ability to just hear the difference between them ... and if the difference is there, it's very subtle and so minimal that i simply cannot hear any useful difference...

As it happens, I contacted support with this exact question some days ago because I wanted to have better control around the lower volumes. So I asked about documentation, about the possibility to customize via sysex and about the possibility to measure the curves using midi note on msgs. They replied:

For any of our instruments, there are certain mechanical limitations of the keybed itself that affect the dynamic range available for velocity articulation. We include 8 velocity curves to give the user some options in terms of how the instrument feels to play from its keybed. We don't have any graphic representations of these curves--we recommend trying them out by feel and selecting the one that works best for you. There is no way for the user to add or alter velocity curves.

It's good to note that the velocity curves only affect the raw output of the keybed to the internal synth engine, and not received MIDI data. If you wanted to alter the velocity response coming out of the computer, you would do so in the computer.


To be honest, if they really had this information available, from where I stand it'd be silly not to share it, so maybe they really don't have it (and have no time to create it). On the other hand, in its current form the curve selection seems to be of very limited use.

From my own experience, there are discernible differences between the different curves, but they are quite subtle. One way you can experience differences between a few velocity curves is by using preset Ensembull (I think it is F2 P43?) and playing as softly as you can. In some curves you can hit a very low volume (leading to a soft somewhat woodwind-like timbre), whereas in others it's nearly impossible (leading to a more "brassy" timbre).
--
gear: prophet rev2 16 voice, yamaha gt-2, casio wk-7600, Roland Integra-7, supercollider, ardour

links:

https://www.youtube.com/stefaanhimpe
https://soundcloud.com/stefaanhimpe
https://technogems.blogspot.com
https://a-touch-of-music.blogspot.com/

Razmo

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Re: Information about the Velocity Curves?
« Reply #9 on: August 20, 2018, 03:16:58 AM »
i do not want to assume anything here, i want DSI to describe them so that I'm certain about their curves, because i really do not have the ability to just hear the difference between them ... and if the difference is there, it's very subtle and so minimal that i simply cannot hear any useful difference...

As it happens, I contacted support with this exact question some days ago because I wanted to have better control around the lower volumes. So I asked about documentation, about the possibility to customize via sysex and about the possibility to measure the curves using midi note on msgs. They replied:

For any of our instruments, there are certain mechanical limitations of the keybed itself that affect the dynamic range available for velocity articulation. We include 8 velocity curves to give the user some options in terms of how the instrument feels to play from its keybed. We don't have any graphic representations of these curves--we recommend trying them out by feel and selecting the one that works best for you. There is no way for the user to add or alter velocity curves.

It's good to note that the velocity curves only affect the raw output of the keybed to the internal synth engine, and not received MIDI data. If you wanted to alter the velocity response coming out of the computer, you would do so in the computer.


To be honest, if they really had this information available, from where I stand it'd be silly not to share it, so maybe they really don't have it (and have no time to create it). On the other hand, in its current form the curve selection seems to be of very limited use.

From my own experience, there are discernible differences between the different curves, but they are quite subtle. One way you can experience differences between a few velocity curves is by using preset Ensembull (I think it is F2 P43?) and playing as softly as you can. In some curves you can hit a very low volume (leading to a soft somewhat woodwind-like timbre), whereas in others it's nearly impossible (leading to a more "brassy" timbre).

This is a typical response from support, when they do not want to talk about something... and I'm not surprised to be honest...

I actually might not care, if i could hear any differences between the different curves, because then i would go for the one i thought felt the best... the problem is that i cannot feel any real difference with any of the Aftertouch curves at all, making the point of having the curve choice pretty much useless...

I'm actually pretty satisfied with Curve1 of the velocity sensitivity... my main problem is with the Aftertouch curves... i feel i have to almost break my finger to get into the higher range of Aftertouch values, almost as crazy as with Roland keybeds... I'd really like to be able to reach a maximum pressure level with less pressure applied to the keys...
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Razmo

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Re: Information about the Velocity Curves?
« Reply #10 on: August 20, 2018, 04:12:35 AM »
I can add some info on the pressure curves because i just tested them a bit... I noticed the following (just a simple patch routing pressure to the pitch):

1. when I applied max force on the keys, all pressure curves sounded the same in pitch... this tells me that none of the curves had lower dynamics.

2. when I applied medium force on the keys, the four pressure curves from 1 to 4 increased in pitch, telling me that the four curves are probably just upward logarithmic (curve 1 probably being linear, and the following being increasingly logarithmic).

This makes curve 4 most responsive on less pressure which is generally good for controlling low amounts in the ModMatrix, like for example vibrato amount, which usually is applied in very small amounts.

But for pressure modulation that have large amounts, curve 1 is more appropriate, as it will give you a feeling of better control of the pressure from low to high.

A trick to make the pressure more sensitive (greater reaction at lower pressure) with curve1 and modulations that require lower amounts (like vibrato), is to simply set a higher modulation amount in the ModMatrix... that means you'll be able to press too much vibrato in, but you'd have to press rather hard to get there... still it's a balance though... Personally I found that my prefered curve for pressure was Curve3... giving a medium logarithmic upward curve... with this I get a reasonably good pressure->vibrato feel, but still enough dynamics in the curve, that large amounts of modulation in other parameters have a reasonable resolution.
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Re: Information about the Velocity Curves?
« Reply #11 on: August 20, 2018, 05:13:39 AM »
Agree, the Rev 2 seems to have opposite issue to the P12 with Aftertouch. On the P12 I struggle to not trigger it unintentionally, on the Rev 2 you really gotta want it.

As for info on the curves, it is hard to fathom how they could not have any info on the curve shapes honestly. They did put them in there in the first place. I donít see why they wouldnít release it either.

dslsynth

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Re: Information about the Velocity Curves?
« Reply #12 on: August 20, 2018, 12:20:54 PM »
i really do not have the ability to just hear the difference between them ... and if the difference is there, it's very subtle and so minimal that i simply cannot hear any useful difference...

One idea could be to make a preset using noise as oscillator and use a square LFO to modulate the volume. Route velocity to the LFO frequency and compare the observed LFO frequency with the velocity reported in the corresponding Note On message. This may help you get a sense of the velocity range. Will work with other presets using the same concept of routing velocity to a parameter easily observed in the output.

Disclaimer: this idea was presented on a Monday! . o O ( :-X )
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Re: Information about the Velocity Curves?
« Reply #13 on: August 20, 2018, 06:02:55 PM »
Another idea would for DSI programmers to actually tell us how they programmed those curves. Unless they themselves donít know ?
 ???
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cbmd

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Re: Information about the Velocity Curves?
« Reply #14 on: August 20, 2018, 06:35:18 PM »
From what I could glean from comments in the code.  Offset refers to some number of low vel/pressure values being set to offset value.

Velocity:
Curve 1: linear
Curve 2: 1.5 exponential, 0 offset
Curve 3: 2.2 exponential, 10 offset
Curve 4: compressed, 26 offset
Curve 5: custom curve, 33 offset
Curve 6: 1.5 exponential, 33 offset
Curve 7: 2.3 exponential, 50 offset
Curve 8: compressed, 33 offset

Pressure:
Curve 1: 3.0 exponential, 1 offset
Curve 2: 1.8 exponential, 1 offset
Curve 3: custom
Curve 4: 3.0 exponential, 1 offset

Hope this helps!
Sequential

Re: Information about the Velocity Curves?
« Reply #15 on: August 20, 2018, 07:43:09 PM »

Pressure:
Curve 1: 3.0 exponential, 1 offset
Curve 2: 1.8 exponential, 1 offset
Curve 3: custom
Curve 4: 3.0 exponential, 1 offset

Hope this helps!
1 and 4 are the same?

cbmd

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Re: Information about the Velocity Curves?
« Reply #16 on: August 20, 2018, 10:08:18 PM »
Looking at the tables, they are not the same.  Comment is incorrect.
Sequential

Re: Information about the Velocity Curves?
« Reply #17 on: August 21, 2018, 02:05:33 AM »
Hey thanks for info mate. Much appreciated!

Razmo

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Re: Information about the Velocity Curves?
« Reply #18 on: August 21, 2018, 02:28:01 AM »
Looking at the tables, they are not the same.  Comment is incorrect.

Well, then what is the right curve for number 4? ... i would have assumed that curve 1 was linear, but since that is exponential 3.0, and the second curve is less exponential, then i would probably assume that curve 4 is in fact the linear one?

And what about the "custom" one? ... i often see curves on other synths where one of them has the first half of the curve exponential, and then logarithmic for the second half... might this be the case with curve number 3?

The funny thing is, that curve number 4 does not feel linear... it feels very logarithmic... I'm wondering if the direct control signal coming from the aftertouch strip is in fact logarithmic or exponential, and if it is being fixed into linear on curve 1, by using a logarithmic change of 3.0? ...

just wondering... I'm happy with the info you gave, I'm just wondering because the info was very different from what i would have expected.
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Re: Information about the Velocity Curves?
« Reply #19 on: August 21, 2018, 08:17:05 AM »
Yes, thank you Carson for taking the time to look at the code and telling us. Much appreciated !  :) 8)


Minimoog D (vintage), OB6 (Desktop), Oberheim Matrix-6 (MIDI Controller), Prophet REV2-16, DeepMind 12, VC340