Note-off velocity?

QuasiUnaFantasia Example: the key is pressed to the bottom, and now you release it halfway up. In response the damper is lowered somewhat. Now you might just push the key back down to the bottom again, and the damper would be raised again.

The dampers (with either foot or finger) move by a relatively large amount, say about 1cm. The actual damping effect, buzzing and everything we are talking about takes place in a relatively small area: from when the felt start touching the string (when damping) to when it is completely pressed against it -- I think that's about 1mm. Plus, the first position depends on the volume of the note (louder notes are caused by strings vibrating a larger amount). Pretty complicated to keep all of this in a software. Plus, even in a acoustic grand, the dampers are seldom correctly regulated with the pedal: i.e. some notes are damped earlier and some are later. Try it:

• press the pedal and keep it
• press and release a note
• slowly release the pedal but not completely, only until it "just starts" dampening that note (at the volume at which is playing)
• keep the pedal still
• try the same note at the same volume again, and adjacent ones: likely they will behave differently (this is a regulation defect)
• keep the pedal still
• try one note at different volumes: the louder ones are damped, the softer ones are not (this is an acoustic characteristic which I doubt any software correctly reproduces -- but then I am not sure any artist take advantage of)

Bottom line: should we care about note_off velocity as way to get a digital piano become a better approximation of an acoustic piano? I dunno.

I'm perfectly happy about the note-off velocity always being zero. My problem was that I didn't understand the purpose for this part of MIDI. I suspect that various makers of VI's do use this velocity for something, but I don't believe they use it for something meaningful in the context of an acoustic piano (at least, that is how I view it now).

Some digital pianos don’t even send the note-off message and instead send a note-on with value 0 to denote that the key has been released.

CyberGene Some digital pianos don’t even send the note-off message and instead send a note-on with value 0 to denote that the key has been released.

In fact, note-off encoded as note-on with velocity zero is still the norm in the majority of midi files found in online repositories… But the current line up of mid and high level digital pianos, all send note off (or at least has that feature in their midi specifications), with a few surprising ommisions…

When I last tested with a MIDI app, on the NV-10's sound engine the note off velocity seems to affect the volume of the release sample as well as the volume of the hammer noise. I couldn't tell any difference in the nature of the sample itself.

I never tested my VSL D274 or even the garritan for note-off differences (now I am curious… maybe they are so subtle thatend up meaningless) but I was certainly not expecting release samples at different velocitiea in onboard piano engines (much more limited in sample memory).

vagfilm I don't recall what I was expecting, but if not new samples, at least different duration (a stacatto release might cut off the release sample earlier) or filtering of some kind; didn't hear any of that.

I just remember coming away with "oh that's it?" And thinking no wonder it's such a non-issue. I can just hear Mac muttering "I could've told you that," under his breath.

I will try to find some time to test this with mock midi files…

dore_m I mean, for years as a kid I wondered why I "ride the pedal", and then I forgot about it. But now I know I'm just controlling the brilliance, sustain, and preventing "muddiness" unconsciously.

That's one of the reasons, why detailed pedaling instructions are usually not written into the score. There have been written entire books on pedaling, as it is expected that you know how to use the pedal.

Digital pianos aim at the goal that application of the correct technique doesn't sound wrong through built-in amplification, however they don't provide any means to practice that technique.

Recorded sample libraries cannot sound wrong. There is no need control anything, which has already been picked up by microphones, selected for perfection and stored away to be triggered through MIDI. Things like riding the pedal simply aren't necessary.

QuasiUnaFantasia it? When a physical key is let go in an acoustic, gravity pulls, and the damper drops, where does velocity play a part?

MIDI was not designed to capture the events of digital pianos but to interconnect synthesizers and computers. In a synth, the note-off velocity can be used to control the Release component of the ADSR envelope.

In an acoustic piano the velocity of releasing a key has impact on how fast the key damper touches the strings and therefore on the sustain. This can have a noticeable impact on sound, especially in slower pieces that do not rely on the sustain pedal. Have a listen at András Schiff playing the WTC at the BBC Proms 2018 for several examples. But one could argue that this effect is minor when considering a wider repertoire.

In a digital piano, the note-off velocity can be a constant value or represent the release velocity at a given point. This feature requires measuring the time difference between a pair of key sensors - and this is the reason why DPs that rely exclusively on hammer sensors cannot implement it. As @CyberGene pointed out, some implementations, notably Yamaha's, represent the key release not as a single event but as multiple events. This better simulates the key damper mechanism of the acoustic instrument. Improvements to how series of note-off events are managed is actually one of updates to the MIDI 2.0 spec. In any case, the primary use case of note-off velocity is to control the Release of synth sounds.

Gombessa , on the NV-10's sound engine the note off velocity seems to affect the volume of the release sample as well as the volume of the hammer noise. I couldn't tell any difference in the nature of the sample itself.

The CA98, which has the engine as the NV-10, processed the note-off velocity by changing the sound volume of that note. It can tested with a MIDI file designed for this purpose. Do not remember the impact on the hammer noise. But why should they also change the volume of the hammer noise? In an acoustic, the release velocity only impacts the damper and the action of that key, not the overall hammer movement, including how the hammer returns to its rest position.

arc But why should they also change the volume of the hammer noise? In an acoustic, the release velocity only impacts the damper and the action of that key, not the overall hammer movement, including how the hammer returns to its rest position.

Well, actually in an acoustic grand the key release has a (small) impact on the noise the hammer makes when returning to its rest position from either the checked position or from its escapement position. If you want to be totally realistic the digital piano should also take into account which ones of these two positions the hammer was before releasing, hence if the previous note was loud (checked) or soft (escapement). In my opinion this is too hard to implement right compared to the provided enhanced realism. So I agree that the main thing to take into account is the way the sound is dampened.

arc As @CyberGene pointed out, some implementations, notably Yamaha's, represent the key release not as a single event but as multiple events. This better simulates the key damper mechanism of the acoustic instrument

Yes, in fact in theory the damper might not damp completely, and then be raised again creating a number of effects. Not sure how common this is done by competent pianist, but I can attest that it is besides the capabilities of the average pianist, also because the average piano is seldom well regulated in this regard, as the Reblitz books points out. The first sentence of said book, when describing the regulation procedure for the dampers is "You are about to enter the most tedious and long process of regulating a piano" (quoting for memory, likely a paraphrase).

arc ave a listen at András Schiff playing the WTC at the BBC Proms 2018 for several examples.

There is a very long, edited (pitch shifted) and unofficial and monetized version on

Or the "official" page has only a 2 minute excerpt as far as I can tell.

https://www.bbc.co.uk/events/e92fbp

@arc If you could point out one particular example from either recording, that would be very appreciated