ORIGINAL: pianodano
Regardless of any difficulties in making it work to at least achieve the old benchmarks under the current os, the real and central issue appears to be (imho) that midi has simply been relegated to the back burner and the resources are directed towards including the latest wizbang vitural audio thingamajig or new widget to make the (your choice of user) buy in at the continued expense of the intensive midi users who have, for far to long, been thrown only occasional little tidbits.

It's not MIDI that's been on the backburner, but dedicated clocks within the computer and OS for audio / MIDI timing. Because of the way DAW's have become universal / native applications that boast the feature of widespread compatibility across a variety of consumer and pro audio and MIDI devices, there is a requirement of certain basic support from the hardware and OS - and dedicated clocking for MIDI communications hasn't been included. The solution *could* be as simple as designating that MIDI interfaces (be they standalone boxes or the USB controller built into a keyboard) have their *own* timing source, or that there be a truly universal time-stamping protocol for the next generation of MIDI spec that takes advantage of the current stability of audio clocks, since most people using a DAW have some sort of audio device with its own clock. That way, your MIDI would be as stable timing-wise as your audio. But it would require that all of the MIDI manufacturers adopt this approach and incorporate the protocol into their drivers, and that the DAW programmers take advantage of the timestamps. Not impossible; just a standards hurdle like all the rest.

"it was locked forever in monaural sound"

I'm dismayed that anyone would think that there is some downside to enjoying a fine classical recording in the mono format.

Most of my favorite Classical recordings are in mono and I use a mono playback system to enjoy them to their fullest.

best regards,
mike

If the computer is translating data in as uninterupted a state as possible then timing issues become almost nil. The speed and bandwidth issues pretty much exced what is needed for high quality reproduction.

Actually, that's not quite the case. Modern transports involve assembling data (MIDI or audio) into packets, which always introduces some amount of delay. This is a serious issue when packing/unpacking MIDI data to/from USB or Firewire packets, and puts a lower bound on what kind of latency can be achieved. If you want to use Ethernet/Firewire/whatever for MIDI transport, _and_ you want to keep jitter to imperceptible levels, then some level of buffering delay is unavoidable (and quite acceptable, IMHO).

That said - it's technically quite possible to get MIDI latencies on the order of 1-2 millliseconds or so, and jitter of well under a millisecond, if the driver stack is designed properly and the operating system and other drivers don't get in the way . Unfortunately, those are pretty big "ifs" with Windows...

Russell T. Graham is on the right track, btw...

- Jim

ORIGINAL: Marah Mag

What do you (all) make of this, wrt jitter, accuracy, a computer's ability to translate a performance..... that kind of stuff....

Glenn Gould in Re-performance
Bach’s Goldberg Variations
http://zenph.com/sept25.html

Interesting. I haven't had time to actually listen to the clips on the site yet, but I poked around for some info on what exactly they're doing in terms of their "translation" from classic classical recording (say that 5 times fast) to "reperformance." Maybe there's something I'm missing on the site, but it seems like they're keeping their process pretty close to the vest. I can't find info on whether they're using audio-to-MIDI triggering, what OS they're running on, what sequencing software (if any), whether it's a proprietary system or platform, etc. Without knowing whether they're running some combination of publicly available products, it's difficult to conjecture as to how much the typical MIDI timing issues might affect the performance.

That said, it's certainly an interesting concept. If they *are* in fact using one of the more popular sequencers / DAWs, then I'd be curious to know what they have to say about the typical MIDI jitter issues, and to what extent it may or may not affect the "nuances" or "anomalies" that they talk about as being signatures or trademarks of these classic classical recordings that they are "reperforming."

ORIGINAL: Jim Wright

Russell T. Graham is on the right track, btw...

Well, thanks. Doesn't seem to help much though, unless some MIDI interface manufacturers want me on their boards, or are reading this forum.
We'll have to wait and see what happens.

ORIGINAL: Marah Mag

Fascinating though. Is the reperformance really "by" Glenn Gould? Does he get performance royalties on CD sales?

...
...

Would be interesting to run play the original recordings on top of the reperformance. They should line up exactly Presumably they'd've done that as part of their proof...?

Good questions.
It reminds me also of a CD that I have, that I was very excited about when I got it, of a "reperformance" (though I don't think that's the word they used) of Gershwin playing some of his own compositions, including Rhapsody In Blue. If I'm remembering it correctly (the actual CD and liner notes are in storage, having been converted to MP3), the technicians and producers rigged up a player piano to control robotic arms that then played a concert grand piano, and thereby "played" Gershwin's own piano rolls on a higher-quality instrument. I don't recall whether there was any MIDI capture involved, but I recall wondering at the time just how closely the performance was to the way Gershwin actually played it - having used player pianos in the past, I'm aware of how the various levers and settings on the instrument can mechanically affect the playback speed, dynamics, etc.

EDIT:

Hey - what happens when you reach 1000 posts here?

RTGraham:

Without knowing whether they're running some combination of publicly available products, it's difficult to conjecture as to how much the typical MIDI timing issues might affect the performance.

Yamaha has completely sidestepped all of the typical MIDI timing issues.

The Disklavier uses a special 'extended' form of MIDI that Yamaha developed ("XP MIDI"), but can also use regular MIDI.
The Disklavier also contains a dedicated computer running some kind of realtime OS that's connected directly to the sensors and actuators.

There are no MIDI DIN cables between the Disklavier computer and the sensors/actuators -- and certainly no USB or Firewire driver stack, and no Windows (or Mac) OS.

See http://zenph.com/midi.html for a brief comparison of XP MIDI with regular MIDI.
"Microsecond timing". "1024 levels of Note On, Note Off and 'Touch'. 256 levels of pedal position.
Their description is a bit off (regular MIDI doesn't have 128 levels of Note On; it has 127 velocity levels, because velocity 0 == Note OFF...)

From Yamaha's lit:

Powerful Pro MIDI Data Format Holds Expanded Performance Information
To achieve its superior standards of recording and playback performance, the Disklavier Pro Series generates extra MIDI data to accommodate precision parameters. All essential data such as hammer speed, key release speed and pedaling is recorded and reproduced within the standard MIDI format, enabling full compatibility with other MIDI devices. For recording piano performances with even further subtlety and detail, the Disklavier Pro Series also lets you select the new Yamaha XP MIDI data format.

Pro MIDI Data Format
This expanded format utilizes general-purpose controller numbers in the MIDI specification to record additional performance data including key speed and stroke depth, delivering enhanced levels of recording sensitivity and precision. This multi-mode flexibility allows interaction smoothly with existing MIDI configurations and reproduces data generated in either XP or standard mode, with automatic selection of the appropriate playback format.

How is Zenph reconstructing the reperformance data? Good question. A wild guess would be a combination of a) some really clever audio data analysis, guided by b) a digitized score of the Goldberg Variations, with c) some expert tweaking of intermediate and final results by an expert human.

- Jim

ORIGINAL: b rock

How is Zenph reconstructing the reperformance data? Good question. A wild guess would be a combination of a) some really clever audio data analysis, guided by b) a digitized score of the Goldberg Variations, with c) some expert tweaking of intermediate and final results by an expert human.

For more information: Piano Resurrection.

Wow - and there you have it. Thanks, b rock, for posting that. And thanks, Jim, for pointing out the XP MIDI implementation that Yamaha is using.

It still leaves the question of, "to what extent is the artistry merely the sum of its parts (i.e. high-resolution hammer velocities, release velocities, pedal positions, timing, etc.), and to what extent is there something intangible that exists only in the actual human performance, at that moment, coming from that individual?"

I'm curious now to listen to these recordings - the original Gould and the reperformance.

ORIGINAL: Marah Mag

ORIGINAL: RTGraham

Hey - what happens when you reach 1000 posts here?

I'm not sure. When I hit 999, I created a new name and started again at 0.

Just keep your avatar when you switch, that way we can go "Oh yeah...that's the watercolor gal"...

(that is a watercolor, right? Obviously I'm no art expert...)

ORIGINAL: Marah Mag

ORIGINAL: RTGraham

I'm dying to ask why, but I sense that my leg might be getting pulled here.

I wouldn't pull your leg. Bascially, I wanted a different name. And the post count didn't make any difference to me. It was fun starting over.

I carefully waited until I made post 999, or maybe I waited until 1000. But the next day I saw that it was only at 996. I'm not sure how that would have happened.

Fair enough.

ORIGINAL: Marah Mag

ORIGINAL: RTGraham

I'm also wondering where you got the cool avatar - noticed it on your old profile as well.

It's a photoshopped photograph. I probably used a watercolor filter, or something like that.

Cool.

ORIGINAL: Nick P

Glad to see this thread still "charting".

Heh.

One day this thread will pop up in somebody's search, and they'll read through it and ask,

"MIDI Jitter? What's that? Oh wait - I think I've heard of that - that's one of those problems people had to deal with in the first decade of the 21st century. Glad my MIDI data is word-clock-locked and sample-accurate now; I don't know what I'd do if I didn't have 384kHz MIDI resolution."

ORIGINAL: Nick P

From what I gather, it's the way MIDI is processed up and down the pipe by the OS which needs reworking. MIDI events probably sit in the queue like every other process waiting to get worked over by the CPU. I think that's where the problem lies.

Pretty much. If you ditch all the technical details. Standalone boxes (e.g. Akai 'MPC' boxes) show that MIDI DIN 1.0 can deliver pretty good timing, when handled right. (Not perfect timing, but good enough for most purposes).

And, MIDI is a serial interface - one note at a time - even when you play chords and uch. That's always been an issue.

"Serial" doesn't have much to do with it. USB and Firewire are both serial protocols; they just move bits a heck of a lot faster. MIDI DIN is a slow protocol by current standards - only about 3K bytes/second (31.25K bits/second, moving 10-bit words including start & stop bits, yada yada). However, because MIDI DIN is dedicated to MIDI and nothing else, those few bits can be placed "right in the pocket", which works well unless there's too much data (pitchbend is notorious) going over the wire at any point in time. Then, MIDI lags occur. (Of course, it only 'works well' if nothing else in the chain screws things up - like an OS or driver that doesn't maintain the timing accuracy of the bits coming 'off the wire').

There needs to be a MIDI 2, but I don't think there would be enough interest now.

Oh, there's definitely interest. The standards folks are still working on "HD MIDI" (Google it) -- these things just take time to percolate. If HD MIDI doesn't happen, something else will come along eventually. Don't give up! (Not that this helps any musician struggling with a DAW today, unfortunately....)

- Jim

ORIGINAL: pianodano

I don't agree with some of that. The thread has just been speaking about a Disklavier.

Duly noted. And as mentioned a few posts back, the Disklavier apparently has a more robust, "enhanced" MIDI implementation, specific to Yamaha's products, that achieves greater resolution and precision than the MIDI spec that other interfaces and instruments use. But as this thread originally started as a discussion about MIDI timing stability in general, and more specifically the issues involved in accurate MIDI recording and playback on a standard-OS computer system, it's interesting to compare the Zenph / Disklavier situation with that of the typical studio. I think what we're all clamoring for here is widespread public access, within the DAW platforms that we're already accustomed to using, to the kind of resolution and accuracy that Zenph is apparently achieving through proprietary means. Because, in theory, the professional-level producer / musician / DAW consumer should have access to a level of quality from MIDI at least equal to that of audio. But as we've all seen, audio is more exciting, gets more attention, and has more obvious consequences when it gets something wrong - for years, anybody who complained about MIDI timing has been dismissed as being either paranoid, delusional, or too picky.

MIDI came out in 1982. That means it was probably being worked on as early as the late 1970s. You can't expect that it would still be able to compete with the latest transfer speeds and methods. That's why I wish they would do a MIDI 2. It's been talked about for years, but never acted on. Basically, all of these high-tech digital workstations are still shuttling MIDI in, out, and thru (pun intended) their innards using a technology that's not been updated in over 25 years!

What is interesting is that when you measure playback jitter in windows you can see it is about the same generally across applications. What varies is the pattern it takes. It is good to think of jitter as tempo changes. You could create the same effect by doing a tempo map in Sonar. So when a midi event plays say 1ms earlier than it should based on tempo, the tempo has increased slightly. It also means that every sequencer overcompensates in order to keep the tempo correct. So if a note plays 1ms early then at some point a note or notes have to play late by 2ms in order to push the tempo back to the expected value. Every sequencer does this I think in order to keep lengths at what they should be. I think syncing to something would be impossible for example if jitter was not compensated for in this way. But when you look at clocks in the sequencer you may think things are better than they are because you just see a 1 tick difference up or down when in fact the turnaround is 2 ticks. You only realize this when you measure the midi data train itself and see what the actual timing of each midi event is. In Sonar the pattern can be very regular: 2 events at 120bpm, next note delayed about 2ms, next note played ahead about 2ms, and the pattern repeats. At a different tempo you get a different pattern. Other sequencers vary the pattern a bit but the 2 up/2 down seems pretty consistent whether it occurs in succession or is spread out a bit over time. I haven't measured a windows sequencer yet that differs from this and I've measured a bunch. OSX isn't any better. In fact in some ways it is worse (under load things get loose). You want tight timing? An Amiga or Atari is it. An Amiga is slightly better but both are light years ahead of windows or osx. You're talking variations that average about .2ms and never more than .5ms.

Jon

ORIGINAL: Nick P

MIDI came out in 1982. That means it was probably being worked on as early as the late 1970s. You can't expect that it would still be able to compete with the latest transfer speeds and methods. That's why I wish they would do a MIDI 2. It's been talked about for years, but never acted on. Basically, all of these high-tech digital workstations are still shuttling MIDI in, out, and thru (pun intended) their innards using a technology that's not been updated in over 25 years!

well at least midi is one of the only standards in audio that work ****ing 99,99% of the time you use it - actually we should be more than happy that we still have it almost everywhere - my old analog midified synths kick those plugs ass - in latency AND sound AND ease of editing...btw i never had any midi jitterproblems - eventually its all those friggin usb midiinterfaces that ruin the performance...


edit: ... transfer of Note On/Off command takes from 0,64 to 0,96 ms via MIDI and from 0,64 to 2,464 ms via DCB....