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With the advent of the new Kawai VPC there has been much discussion about the concept of the touch curve for a dp.

Since I use software piano sounds I have utilized these touch curve adjusters for some time now and something always puzzles me about them.

I will use Pianoteq for my example because that product has the most vivid example of this puzzle.

In Pianoteq the touch curve is associated with each of the presets within the product. That seems odd to me because I would think that the touchcurve would be associated with the instrument you are playing ... not the particular sound you are generating. It would seem natural to me to assign a touchcurve ONE TIME in the header of the product somewhere and never change it unless you changed the instrument.

But, that is not what I see. I see a different touchcurve for every preset and many are significantly different than others. It appears that the touch curve is simply another parameter within the preset that affects the sound and not something defining the touch sensitivity of the digital piano sending the midi signals.

What say you ?

How does this compare to sampled pianos software?

Modeled piano is synthetic so you are not really changing instruments. I can understand the touch curve being customized to suit a preset. It is all just code.

Sampled piano would be more consistent as it is derived from actual properties of a physical piano, I am thinking.

It works exactly the same.

The touchcurve must be defined for each preset.



Well, then why does the Kawai VPC VST controller contain a unique touchcurve for each of 4 different software packages ? What good is a touchcurve within the instrument if you are able to apply separate touchcurves within each preset of the sound software ?

It makes no sense to me.

The designers of each software piano may have used a different keyboard controller as their reference, so each package may be optimized for a different controller response and each piano within a bundle could even be optimized for a different controller response. Then there is the subjective issue. Maybe you prefer a different touch (regulation) for different pianos. In reality, I use the same velocity curve for both the American D and the Vintage D (I actually leave the piano software velocity at the default settings and change the velocity curve(s) with an external program), but I probably play them a little differently knowing how they respond differently to my playing. Same situation playing two different acoustic pianos though. You adapt to their regulation don't you? And perhaps have one regulated differently if you find it too different from others you like.

As I understand it, there are two mappings (transformations) involved in generating a DP (or synth) sound:

1. The mapping of actual key velocity to MIDI "velocity" values;

2) The mapping of MIDI "velocity" values to the loudness of the generated sound.

Adjusting the keyboard "touch" characteristics (through a software menu, or a knob) changes mapping 1. And it affects all voices.

Mapping 2 is determined _for each voice_, in the definition of that voice.

On the Casio PX-350, there's a "Rock Piano" voice. As well as being harsh, it's _loud_. The output sounds like a piano that's been passed through a compressor. It's very tough to play that voice softly; even fingered "p", it comes out "f". It's just what you need to be heard over a band, without pounding the keyboard.

I'll bet the effect was achieved by changing the MIDI-velocity-to-loudness mapping for "Rock Piano".

An extreme example of that capability is in a proper "organ" voice. If the MIDI velocity is greater than 0, you get full volume.

I hope this doesn't add to the confusion . . .

. Charles

If you know it is "exactly the same" why specify Pianoteq at all and not just give reference to all piano plug-in software?

Because at the time, I just knew that Pianoteq works that way. I hadn't checked on the others specifically. Truth is, I still haven't ... I just went back and looked Vintage D and found it to be . Color me lazy.

That makes sense.

However, it is my understanding that the MIDI values generated by key presses vary between digital values from 0 to 127 and should be set at the factory. They should be not have to be adjusted by the user.

Also, in the case of the Kawai VPC the user must do this mapping (on the instrument) for each software package. You would think each software package would be happy to receive MIDI values between 0 and 127 regardless of what they do with them after that.

So, again (In my mind) the logic breaks down.

dmd: My piano cannot reach velocity 127. I can use the piano software's velocity curve to compensate.

Also, consider calibration.
How hard must you strike a key to reach to 127? That may vary from one keyboard to another.
How hard must you strike a key to reach to any given velocity value? That, too, may vary from one keyboard to another.
The velocity curve allows you to adjust MIDI velocity vs. strike velocity over the entire range.

Good that this issue is up for discussion.

I think velocity/key touch things are confusing when using keyboard and software sounds. It's even not so easy to figure out what's the best setting is when playing with inbuilt sounds (because it's very easy to adjust to different key touch levels, and key touch also makes sound more mellow or sparkling), and it's much more confusing with software, because then you not only have to figure out key touch levels on keyboard that corresponds naturally with software sounds, but also have think about software velocity as well.

In my opinion, I find it strange that keyboard key touch settings also change sound on software instruments... It's odd.

I did not locate nearly enough information when I searched for it using Google.

It makes sense that each piano model would have a personality to communicate to the voice software, (internal or external), and that the software would have a general personality to communicate to potential keyboards......each influenced by the gear used during programming/writing the code.

Seems to me that the VPC1 has been fine-tuned to speak clearly to the 4 programs featured. In alter-universes such as graphics there are preconceived parameters to choose from for common applications much like selecting from a list of popular printer's drivers. With virtual instrument software, this would be something more often performed by seasoned users.

In the VPC there remains a degree that is subjective and room for customization left for the user. But the "out of the box" gets them to a plateau at a high enough elevation to produce favorable results if the user does not make any adjustments. ...so I am thinking at least.

Exactly !

But you should only have to create one velocity curve to compensate for that.

That is why it doesn't make sense to me to have to enter a velocity curve for each preset in the software. The velocity curve for a given instrument should be constant. Once you have it ... you have it.

I'm not sure what you mean by "preset", nor what you mean by a separate velocity curve for each preset.

In any case ... I have several piano libraries. I set the velocity curve for each of them. Some would be fine to my hands and ears if they shared the same curve. But others not.

So, I'd need only one velocity curve to compensate for the piano's touch sensitivity and responsiveness. But I must still alter the curve to suit each particular piano library, because:

1. They vary. I can't imagine that every acoustic piano responds to the touch in the same way. Nor can it be that they're all recorded in the same way.

2. My sensibilities and judgements must surely differ from one piano library to another.

Well, you said you have several libraries.

Let's pick one example. I assume you have Galaxy Vintage D.

Load up Vintage D.

Select BRILLIANT POP from the global presets.
Check out the velocity curve. It is increasing from left to right from 0 to 127.
BEND it to something else.
Save this multi as TEST.

Then select CUT-THROUGH from the global presets.
Check out the velocity curve. It is increasing from left to right from 0 to 127.
Now you have to change the velocity curve AGAIN.
This is the part that makes no sense to me.

If I have already set the velocity curve for my instrument I should not have to do it over and over again.


Since, I do have to save it OVER AND OVER, it is not a velocity curve for my instrument. It is a personal velocity curve for how I wish this particular preset to sound when I use it.

And that is fine but Pianoteq goes as far as supplying users with predefined velocity curves which are supposedly matched with a particular instrument. Well, if that is true, why do we have to keep defining it over and over for each preset ?

It would make more sense if they would say the velocity curve is just there for us to modify how the preset functions but please do not attach a particular keyboard name to it.

It would be like my having to keep selecting the audio device driver I am using for each of the presets. IT IS THE SAME FOR ALL OF THEM !!! HELLO ???

Note to MAC: My rantings are not aimed at you. I am just trying to emphasize the ridiculousness of this, as I see it.

OK, now I understand presets.

I don't use them. Well, actually I do. I choose one from the list, the one that goes by the name "concert hall" or similar, depending on the library. (Often this is the default upon initial installation.)

Then I tweak it as I see fit, velocity curves, reverb, and all the rest. Then I save it. That's all I do. And that's all I use (for that library).

So this is why I've never been bothered by (or even been aware of) the problem that you cited.

It really does not affect me anymore because I have stopped trying to develop the "perfect" sound through software packages.

I really just grab one of the presets and play with it as is for awhile just for something different. I may make a quick adjustment to the velocity curve if I wish to keep the volume lower on a particular piece of music. Software sounds have become just a sort of diversion for me now.

I don't really get your complaint. You don't have to change the velocity curve when you changed the pre-set. You changed it because you didn't like the timbre vs velocity of that preset. i.e. you didn't like that preset. So you either modify the settings of the preset (the velocity curve is just one way to modify the timbre of the preset, and the last thing I would change), or you use another preset). I don't expect to like most of the presets in any instrument. I either find one I like best and use it as is or tweak it until I like it.

Am I missing something else you are saying?

Well, it depends upon what you think a velocity curve is for.
If you think a velocity curve is available to allow you to modify the way the software sound is generated for your own personal preference, then modifying for each preset makes sense.

However, if you think the velocity curve is available to allow you to make adjustments in the MIDI signal coming in from the digital piano because your digital piano does not send standard signals (0-127), then it should not be necessary to do it for each preset.

I also pointed out that Pianoteq provides velocity curves (on their website) that have been created to match various digital pianos. That would suggest that the curve is being inserted to standardize the signals being delivered from the various digital pianos. Yet, even with that, it is necessary to put a velocity curve in to each preset. Those two concepts cannot coexist logically.

I think it is to adjust your keyboard response to the response used to create the software piano. That includes making sure your keyboard can actually output 0-127. So one velocity curve should work for all of the presets of any given piano.

You seem to be missing my question to you. Why are you changing the velocity curve for each preset? Apparently because you don't like the way some of the presets sound with just one velocity curve. So you are using the velocity curve to change the sound of individual presets per your individual preference. No law against it, but I would change just about every other parameter before I did that.

I don't know why Pianoteq does anything. But as for using different velocity curves for different pianos, that makes sense to me. Do you expect the timbre variation with key velocity to be the same on a Steinway vs a Yamaha acoustic piano? Of course not. Do you expect the sample linearity to be the same on two pianos when created by different pianists or different technicians during post-processing (with a rare exception these sample sets are not created by machines that produce linear velocity changes). Not very likely. So it's quite likely a user might want to calibrate individual piano sample sets to match their opinion of what the timbre vs velocity sounds like for a given piano. Interestingly, I use the same velocity curve for the Vintage D as the Ivory II American D, but not the Ivory II Yamaha. So the Galaxy people and Synthogy people must pretty much agree about how a Steinway responds, but I don't agree with Synthogy about their velocity curve for their Yamaha.