Polyphonic Aftertouch (or Better) should be standard

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CME are supposed to be bringing out a 37 key XKey sometime this year - apparently you can also link several to make a bigger keyboard but the action sounds like it's pretty clicky and not easy to control. I have a QuNexus which has some clever functions but I can't get used to the keyboard as it requires pressure to activate the keys in the first place but that makes it hard to use aftertouch, ironically I ended up having to disable poly AT as it just activated every time I played, it would be better if you could activate it using tilt but they promised an update over a year ago to the firmware to enable that and it still hasn't happened.

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I'm not "classically trained" but do play fairly conventional music, with bass patterns, chord progressions, melodies in equal tempered tuning. I haven't seen many impressive poly at renditions of such music. Even jordan rudess (who has fabulous chops even if he does seem to be an annoying attention hound) I've not seen him do anything fabulous exploiting poly AT.

Perhaps a non-traditional controller could make poly AT easier to control. Guitarists and violinists can certainly do virtuoso work exploiting poly pitch bending or poly vibrato. It is easy to find youtube virtuosos doing such.

Maybe an alternate controller will some day get traction. After all, the conventional piano keyboard at one time did not exist, though it has been fixed in stone for a very long time now.

Perhaps it is analogous to dvorak computer keyboards, or other non-querty keys. Tests show that any random key layout tends to be faster than querty after it is learned, but querty remains king. It takes too much time to learn a layout, even if it is a bad layout. Doesn't pay most people to get good with an alternate layout if they have to learn the querty layout as well. I really like my TI calculator but the alpha keys are laid out in ABC order. I could run the calculator so much faster if it was querty, even granted that in a vacuum ABC makes more sense.

People have been trying to design a better piano key layout for hundreds of years. One of the most logical layouts, somewhat recycled by many modern alternate controller variants, is the old chromatic button accordion layout. It makes perfect sense. Some people play them great. It made so much intellectual sense that I got a cba and fool with it sometimes, but stink playing it. Rather than the advantage of wanting to learn something new, the money would have been better spent getting an accordion of equal quality with conventional black'n'white key layout. I'm a poor thumb-fingered pianist, but have thousands of hours invested getting as good as I'll ever get. Getting merely competent on chromatic button accordion or any other alternate layout, would at least require investment of hundreds more hours, if not thousands.

One time I did technical consulting for a fellow who patented and tried to market an alternate keyboard layout. Spent his entire fortune on the failed effort. There are zillions of em. He was seduced as were so many over the years, because so many layouts "make more sense" and "ought to be easier to learn and play" compared to 88's.

After he paid the big bucks for high quality injection molds, I installed his keyboard design on my EPS. It "made sense" to me as well. I gave it a good try for awhile, but there were unforseeable difficulties. Some chords, melodies and playing styles were easier, but MORE chords, melodies and playing styles were more difficult than an 88. And the "easier" fingerings put the hand into odd shapes inviting carpal tunnel syndrome if one keeps at it long enough. So after a couple of years I put a conventional keyboard back on the EPS.

There have been zilions of designs to make poly AT easier to control. Maybe one day a design will take off. A long time ago bob moog was working with a developer on a keyboard where the keys slide front to back like sliders, in addition to ordinary movements. So many attempts, yesterday and today.

A lot of the youtube demos are like my old pal who blew his fortune on his keyboard-- The guy is an inventor, not a musician. He lectures on the shortcomings of the 88, shows how his new gadget is easier to learn and operate, and gives a lame demo of its potential, which will be realized to its full potential after the next keith emerson adopts the keyboard, spends thousands of hours getting good on it, and then plays so good that everybody will know how much better the new design is, compared to an old obsolete 88. :)

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mellotronaut wrote:how many softsynths do respond to poly aftertouch?

lots

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Anyone who can effectively use Channel Aftertouch can also use Poly AT... Exact same finger movements

I'm figuring on buying the Linnstrument.

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pdxindy wrote:Anyone who can effectively use Channel Aftertouch can also use Poly AT... Exact same finger movements

I'm figuring on buying the Linnstrument.
Mebbe. I can use pressure for vibrato or pitch bend on monophonic parts (where poly AT feature is unnecessary anyway).

I can use channel AT for vibrato, timbre modulation, or occasional pitch on polyphonic parts. If talented enough to control it, possibly poly AT would be beneficial playing chords + melody on the same keyboard, so that a person could spike the occasional melody note without affecting the simultaneously held accompanying notes.

But many conventional poly things that might be enhanced by channel pressure, are MORE difficult to do the same tricks with poly AT. The Poly AT requires more control. For instance, if you want to do an R&B stacked horn riff, leading into a "shake vibrato" chord. If you have the channel AT set to low enough sensitivity to play the mono notes with no vibrato, then hit the chord and really lean into it for the pressure-controlled shake, can work OK.

Do the same with poly AT, and if set insensitive enough to allow no-vibrato single note line, unless you are real dang good with yer fingers, when you lean into the chord, some notes in the chord will have too much vibrato and others will have little or none.

If for instance using poly AT modulating amplitude, to balance the different notes in a legato string quartet emulation-- All I can say is it will probably take lots of practice before it quits sounding gap-toothed. The notes that happen to be easy to reach, played by the strong fingers of the hand, will tend to be too loud, and the notes that are hard to reach played by weak fingers will tend to be too quiet. Will take a lot of practice to get an even-enough touch to make it work.

I'm not against poly AT and wish all keyboards had the feature, to make people happy with the expressive potential. It just takes a LOT more practice and control, compared to channel pressure.

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OK, everyone dissing poly-AT as nothing special, raise your hand if you ever used it before to the extent of mastering it's use.

Those of us that had/have Ensoniq keyboards with poly AT liked it - my favorite use was to assign the poly AT to filter items. You could do a very cool selective filter setting change on a held chord just by starting a rocking motion in the held chord hand. You CAN and DO get used to having the control. My VFX-SD is for all intents and purposes dead, and it was a sad day when that happened.

It does take practice, but so does learning to use a pitch bend and mod wheel correctly. If I had my way, there would be no joystick based mod/pitch bend control because both have to return to zero when released. A mod wheel, because of it's ability to 'hold' it's position, is a much more musically useful device than just another axis on a joystick that is spring loaded. Breath controllers, for those that know how to use them, add yet another controllable dimension to synthesized sounds - I do not happen to be one of those people.

I truly believe this just came down to economics - the expense of producing keybeds with this capability is definitely prohibitive - particularly 30 years ago.

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audientronic wrote:I don't think I'm buying another keyboard controller until polyphonic aftertouch is standard.
Well, you'd better get to inventing a pressure sensor and mechanical system cheaper than bare switch contacts.

Otherwise stop being a big baby and pay what it costs for a keyboard with the features you need.
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ss
Last edited by codec_spurt on Thu Sep 04, 2014 2:48 am, edited 1 time in total.

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mellotronaut wrote:how many softsynths do respond to poly aftertouch? CS80 ... i love the idea too, but there seems to be a long way to go.
Not really. Any synthesizer that can use velocity could also use polyphonic aftertouch. They're identical.

In code things are pretty much identical. A voice would have a parameter like "velocity" and "polyaftertouch".

Note on (channel, note, velocity): voice allocator picks a voice, voice.velocity = as input; voice.note = as input;

Polyaftertouch (channel, note, pressure): voice allocator locates any active voices playing this note, voice[note].pressure = as input;

It really is that simple.

In fact the easy way would be since there are 128 midi notes, you'd need a polyaftertouch_table[128]. Each voice would own an index to this table, of course, since the voice already should know which note it is playing.

So, polyaftertouch: table[channel][note] = pressure

No searching for voices required. Costs at least 256 bytes.
Free plug-ins for Windows, MacOS and Linux. Xhip Synthesizer v8.0 and Xhip Effects Bundle v6.7.
The coder's credo: We believe our work is neither clever nor difficult; it is done because we thought it would be easy.
Work less; get more done.

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Regarding "pressure" vs. "aftertouch", "poly pressure" is officially the name for the polyphonic message (A) while "channel pressure" is for (D).

http://www.midi.org/techspecs/midimessages.php

(all messages include channel)
  • (8) Note off (note, velocity)
  • (9) Note on (note, velocity)
  • (A) Polyphonic pressure (note, pressure)
  • (B) Control (index, value)
  • (C) Program (index)
  • (D) Channel pressure / After-touch (pressure)
  • (E) Pitch bend (lsb, msb)
  • (F) System
Personally though I don't have any complaints regarding confusion here. The specifier "channel" or "poly" makes perfect sense to me. You could also call them "part/section" and "note" although not really "voice" as MIDI doesn't deal in voices directly.

Regarding after-touch vs. pressure, the difference is merely whether you want to use a noun or verb.
Free plug-ins for Windows, MacOS and Linux. Xhip Synthesizer v8.0 and Xhip Effects Bundle v6.7.
The coder's credo: We believe our work is neither clever nor difficult; it is done because we thought it would be easy.
Work less; get more done.

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Where is that text from? I can't find it anywhere, and Google only points to this thread. That text is even more confusing, because now it's "polyphonic pressure" instead, while the far more sensible term would be "aftertouch" because it's triggered in combination with a note "after it was touched", while there's also "channel pressure / after-touch", for which the needless "/ after-touch" part doesn't even make sense, because THAT value doesn't even depend on a note, as opposed to (what's referred to in that text as) "polyphonic pressure", so WHY even call it "after-touch", and why NOT call "poly pressure" "after-touch" when that's the one that SHOULD be called "after-touch"? (which it IS called, in too many forms, everywhere else I've looked on their site)

FFS, you know what? I'm just glad I don't have to deal with MIDI.
"Music is spiritual. The music business is not." - Claudio Monteverdi

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If you have issues, just look at the official midi document I linked.

To get the truly official version you need to order it, but the webpage should be sufficient to demonstrate that both messages are called "after-touch", although the polyphonic one does not use a hyphen in the documentation I do not believe this is important.

As I said it really doesn't matter. Do you get all bothered by the fact people call sockets, "plugs" ?

Well I do, but I just try my best to use the correct terminology whenever possible. Even I make mistakes sometimes. In the end it really isn't all that important as long as the message is conveyed accurately. If people understand what you mean it doesn't matter how you express it.

Oh it seems they've offered PDF ('bout time!) since may this year.

http://www.midi.org/techspecs/midispec.php
Free plug-ins for Windows, MacOS and Linux. Xhip Synthesizer v8.0 and Xhip Effects Bundle v6.7.
The coder's credo: We believe our work is neither clever nor difficult; it is done because we thought it would be easy.
Work less; get more done.

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I don't care much, because I do understand the differences, but I'm just amazed at how they mix up the naming of two separate features in so many ways. At least as a developer, you have the wonderful freedom to call your "channel pressure" implementation "channel pressure", "channel pressure / after-touch" or "channel aftertouch", and your "aftertouch" implementation "polyphonic aftertouch", "polyphonic key aftertouch", "key aftertouch" or "polyphonic pressure", add or take "-" or "(aftertouch)". I'm sure users appreciate that freedom.
"Music is spiritual. The music business is not." - Claudio Monteverdi

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aMUSEd wrote:CME are supposed to be bringing out a 37 key XKey sometime this year - apparently you can also link several to make a bigger keyboard but the action sounds like it's pretty clicky and not easy to control.
I have been using CME XKey for a few months and poly aftertouch is not that great due key height. Still, great looking hardware, but iRig Keys is being considered.

PolyAT also sends a ton of additional MIDI data compared to AT and could cause bottlenecks in some cases.

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George wrote:PolyAT also sends a ton of additional MIDI data compared to AT and could cause bottlenecks in some cases.
depends upon the controllers update rate, but generally over usb midi or to soft synth its a non issue… a more likely issue is overloading the synth engine due to modulating something very 'expensive' in processing power. (remember its per voice)… again not an issue I've seen on soft synths. (but when i do multi channel midi on my virus, its can sometimes have issues!)

codec_spurt wrote: I can't say I miss it. It's nice. I'd like more though. Poly aftertouch and what is more than that?
Must be something?
Maybe that is the be all and end all.
Let's face it. It's not like it is the holy grail.
most of the expressive controllers mentioned have 3 dimension axis,
an example i use on patches might be
velocity - as normal, attack transients
x - pitch bend
y - timbral changes (cutoff/resonance/eq)
z/pressure - envelope alterations (e.g. sustain level), or other effects , lfo rates, chorus depth.
(and of course with an eigenharp Ive breath and 2 strips, breath control I love for overall envelope control, or just applying effects like reverb levels, or sustain)

for me, the key thing, is not only is this per key, but also its directly under your fingers… no need to reach over to a knob/wheel

many say, isn't it impossible to control all of this?,
and the answer is yes and no :)
a) yes, it requires practice… like any instrument
b) no, as stated before intensity can be adjusted, from off to subtle, to extreme, depending on our requirements (and skills) adjust to taste.
c) no, not every finger has to be applying expression*, often its just the melody line being played by the right hand (ok, you need to get a and b right, to ensure the left hand isn't accidentally adding expression)
d) it can also be used subtly, adding a small amount of expression, can add a bit of 'chaos' to your sounds, in the same way as no two notes played on a guitar (or a even a piano for that matter) can ever be exactly the same… this can give a more natural feel to the sound.
e) you can even just use the expression as 'under your fingers', in the same way as channel pressure is a sum/average of poly pressure, you can do the same with all the above… (very useful for existing instruments that don't support per note expression, but you still want to use the mod wheel / pitch bend .. directly from the keys, so not having to take your hands off the keys)

(as you might tell from above, one skill you do need to learn is how to integrate these expressions into your instruments and patches)

I hope more people will discover the fun and the extra dimension this controllers can give, as they appear to be 'taking off'
I think the linnstrument might be more 'accessible' to some (especially those used to grids)
and of course the roli seaboard to keyboard players (ok i know its expensive… but surely there will be cheaper forms in the future?!)


* note: these things are virtual instruments/controllers, so there are also lots of other ways to help this in the beginning, e.g. using splits on the surface, or other 'intelligent' ways to enable/disable expression on the fly

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