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BT Talks about MIDI timing inaccuracies...

Posted: Mon Oct 08, 2007 6:32 am
by electrolee
Hi Guys,

in this article below BT talks about MIDI and its timing inacuracies and how much it sucks he talks about it about three quarter of the way down the article:

http://www.lunarmagazine.com/features/bt.php

Is this stuff true for all MIDI including say when im programming my midi for the impulse drum machine? Im pretty curious to know because he get quite heated about the issue in the article. can somebody share some light for me about midi?

Cheers.

Posted: Mon Oct 08, 2007 6:37 am
by sweetjesus
semi true .. but hey it hasnt stopped hundreds of thousands of musiciands for close to 3 decades.

maybe bt plays at a different groove quantize if his hair is cut at a slightly different angle and thus changing the whole way he has to approach his album writing style..

Posted: Mon Oct 08, 2007 6:54 am
by electrolee
Intersting...

I would like to hear the difference! I know BT is a pedantic guy (nothing wrong with that) and I have to say that his productions are bloody tight.

So yeah can anbody else share any other light on the subject or some examples maybe?


Tah.

Posted: Mon Oct 08, 2007 7:11 am
by Machinate
obviously midi timing isn't inaccurate as long as it stays in the box. But as soon as you start to use hardware midi it really does become a factor - anyone remember the day where they used to delay everything but the kick drum to make sure the timing was right? Ahhhh, I miss hardware samplers... NOT!

Posted: Mon Oct 08, 2007 7:20 am
by kent_sandvik
Yes, BT really talks about external MIDI HW. Those were the days, you had to really think hard how to make MIDI chains, and so on.. With internal synths and MIDI splitters that's less of a problem today, especially with internal synths.

And with Ableton Live you could make the waves sync perfectly together, anyway!

--Kent

Posted: Mon Oct 08, 2007 7:44 am
by nolus
Well midi has it's limitations, but most of the problems comes from equipment and software design.

When you use midi within a computer program to trigger virtual instruments it not really midi at all, just that you are using the same event types as midi (note on, note off, control change etc.) but the transfer of data should be effectively instant and the number of events you can send at the same time is unlimited for any practical pupose. Any delays must be caused by the software giving to low priority to midi events or by the time it takes for a virtual instrument to recognising the event and react to it.

It's only when events are generated and consumed by outboard gear that the wire protocol becomes significant. The maximum transfer rate of midi is about 3000 bytes per second and a typical midi event is 2 or 3 bytes long - ie. less than 1 mS (or 40 samples in BT speak).

If you are using midi synchromisation then the midi clock pulse is just 1 byte and it is allowed to interupt the sending of other messages so should never be more than one byte late (up to 350 uS say)

If you send a lot of information at once via midi - like on the downbeat where several percusion hits happen at the same time then then the hits will be flammed to some extend becuse of the 1 event per milisecond limit. You'll still hear it as a single event because your brain can't separate events that happen so close together, but the character of the perceived event will be different.

Of course this is all very well in therory but in the real world we have to deal with crappy hardware design. Combined audio/midi computer interfaces seem to give a very low priorty midi data - it's like "sorry I'm in the middle of transfering a 256 sample audio buffer - that midi data will have to wait till I finish". And extrernal midi instruments and drum machines (especially vintage stuff) tend to have a pretty low processing power and often they just can't keep up. Operating systems have some responsibility for this as well, try looping midi data back into your sequencer using a virtual midi cable (Hubis loopback or whatever on the mac) you will see hardly any jitter but you will see a delay determined by the time it takes to hand the data from one process to another and back again - this is determined by the system to large extent.

now try the same test through you firewire or usb soundcards mid output and input - the results will shock you - but there is no reason why it has to be this bad, it's just lazy/simplistic software design in the device drivers.

So in this sense he is right - any practical application involving external gear hooked up by a wire protocol is going to suffer from timing problems unless the gear is superbly well engineered (and there is no reason why it should not be these days).

I just think that too much of the blame is laid on the MIDI protocol itself when the real problem is sloppy equipment and software design.

that will be 2 pence please.

Posted: Mon Oct 08, 2007 8:11 am
by hacktheplanet
Yeah dude man! MIDI has poor timing man cool Atlanta awesome! *laughs* Dude man check it out DJing is awesome sweet! But dude it's cool man *laugh*! Cool dude man man dude!

Posted: Mon Oct 08, 2007 8:55 am
by attackmode
Well even the internal MIDI in Live is not dead on.
There are time variations but they are very small. I think it's nothing one really has to worry about.

Have a look here if you want to read more:
http://www.ableton.com/forum/viewtopic. ... 4&start=30

Posted: Mon Oct 08, 2007 9:17 am
by rbmonosylabik
the_planet wrote:Yeah dude man! MIDI has poor timing man cool Atlanta awesome! *laughs* Dude man check it out DJing is awesome sweet! But dude it's cool man *laugh*! Cool dude man man dude!
At least he takes DJing for what it really is :roll:

Posted: Mon Oct 08, 2007 9:51 am
by rikhyray
sweetjesus wrote:semi true .. but hey it hasnt stopped hundreds of thousands of musiciands for close to 3 decades.

maybe bt plays at a different groove quantize if his hair is cut at a slightly different angle and thus changing the whole way he has to approach his album writing style..
I think everyone knows BT is very good musician who looks, behaves silly, immature, thinking he makes himself look cool. it is his problem but how better is your comment ?
I just see somebody bitter, full of complexes for lack public recognition, envious about someones else success,
trying to make himself taller by cutting heads of others,, hair in this case.
I am no BTs friend, neither fan but it is pathetic how low you go in your comment. I hope for you , you were drunk or too tired.
Regarding the midi matter, there is nothing "semi true " about it, whoever does not know, see, hear it and take into consideration while producing, needs some serious studies. He is emotional about it, his right to feel say what he wants, most people simply live with it, what else can we do except using all possible ways to correct, rectify.
If someone thinks it applies only to old school hardware-wrong, it is even worse with computers, and Live midi is worse then of nearly any apps. I wouldn't be surprised that the reason was frustration of the developers to be forced to work on something so ridiculously obsolete, Perhaps when Ableton started, everyone though by 2005 midi will be dead, it must be frustrating for any intelligent developer to be forced to work with this pathetic protocol, it is against all they studied and common sense as well.

Posted: Mon Oct 08, 2007 9:56 am
by Machinate
rikhyray, coming on here and calling people pathetic and bitter doesn't make you seem as professional as you think you are. People lashing out towards BT because of his image is one thing, you lashing out against other forum users is another.

Be. Nice.

Posted: Mon Oct 08, 2007 10:00 am
by 4.33
the most goddam tight electronic act i've ever heard uses midi only for generating sounds and does all the editing in audio.

you know their name - telefon tel aviv

Posted: Mon Oct 08, 2007 10:22 am
by spiral
the timing litmus test
http://web.webhost4life.com/innerclock/ ... ge&name=34

Take any sequencing device - in a sampler use a tight edited fast transient sound like a rim shot - look at it closely on an editor software application to make sure the start time is tight. On a ROM Player or sequencer with built-in sounds - select a similarly tight percussive sound or patch.

Make certain any sample output or patch VCA/EG settings are set to absolute zero/fastest possible attack time.

Sequence a simple two bar pattern at exactly 120 BPM with hard quantised quarter notes playing only your test sample.

Now play the pattern and at the same time record the audio output into any reasonable audio recording software application at 44.1 kHz for 30 seconds or so - Soundforge, Wavelab etc.

Stop the pattern and open up the waveform of your recording.

Make sure your editor is set to view and edit your waveform in samples rather than absolute time.

Zoom right in on the very front of a waveform (any of them will do) and place a marker - do it at the absolute maximum magnification on screen so you are certain the marker is where the waveform begins.

Now zoom back out and locate the very next waveform in the recording and again, zoom all the way back in and place another marker at the very start of this one too.

Repeat this for at least 8 of your recorded 'clicks' in the recording - 16 is better if you have the patience.

Now 'select' the block between the first two markers - usually clicking in the area with the mouse does the job.

Somewhere on screen the number of actual samples between your two markers will be indicated.

Write this number down.

Repeat this for each 'block' between all markers you have placed.

At 120 BPM - a perfect quarter note interval recorded at 44.1 kHz is exactly 22050 samples.

In a perfect world all your measured 'blocks' should be 22050 samples in length.

Posted: Mon Oct 08, 2007 10:24 am
by TITBAG
rikhyray wrote:
sweetjesus wrote:semi true .. but hey it hasnt stopped hundreds of thousands of musiciands for close to 3 decades.

maybe bt plays at a different groove quantize if his hair is cut at a slightly different angle and thus changing the whole way he has to approach his album writing style..
I think everyone knows BT is very good musician who looks, behaves silly, immature, thinking he makes himself look cool. it is his problem but how better is your comment ?
I just see somebody bitter, full of complexes for lack public recognition, envious about someones else success,
trying to make himself taller by cutting heads of others,, hair in this case.
I am no BTs friend, neither fan but it is pathetic how low you go in your comment. I hope for you , you were drunk or too tired.
Regarding the midi matter, there is nothing "semi true " about it, whoever does not know, see, hear it and take into consideration while producing, needs some serious studies. He is emotional about it, his right to feel say what he wants, most people simply live with it, what else can we do except using all possible ways to correct, rectify.
If someone thinks it applies only to old school hardware-wrong, it is even worse with computers, and Live midi is worse then of nearly any apps. I wouldn't be surprised that the reason was frustration of the developers to be forced to work on something so ridiculously obsolete, Perhaps when Ableton started, everyone though by 2005 midi will be dead, it must be frustrating for any intelligent developer to be forced to work with this pathetic protocol, it is against all they studied and common sense as well.
wow, against very heavy competition you have won Most Pompous Prick on this board - quite the achievement. now go do some yoga and see if the increased flexibility allows you to extract your bald head from your arsehole

Posted: Mon Oct 08, 2007 11:09 am
by 4.33
TITBAG wrote:
rikhyray wrote:
sweetjesus wrote:semi true .. but hey it hasnt stopped hundreds of thousands of musiciands for close to 3 decades.

maybe bt plays at a different groove quantize if his hair is cut at a slightly different angle and thus changing the whole way he has to approach his album writing style..
I think everyone knows BT is very good musician who looks, behaves silly, immature, thinking he makes himself look cool. it is his problem but how better is your comment ?
I just see somebody bitter, full of complexes for lack public recognition, envious about someones else success,
trying to make himself taller by cutting heads of others,, hair in this case.
I am no BTs friend, neither fan but it is pathetic how low you go in your comment. I hope for you , you were drunk or too tired.
Regarding the midi matter, there is nothing "semi true " about it, whoever does not know, see, hear it and take into consideration while producing, needs some serious studies. He is emotional about it, his right to feel say what he wants, most people simply live with it, what else can we do except using all possible ways to correct, rectify.
If someone thinks it applies only to old school hardware-wrong, it is even worse with computers, and Live midi is worse then of nearly any apps. I wouldn't be surprised that the reason was frustration of the developers to be forced to work on something so ridiculously obsolete, Perhaps when Ableton started, everyone though by 2005 midi will be dead, it must be frustrating for any intelligent developer to be forced to work with this pathetic protocol, it is against all they studied and common sense as well.
wow, against very heavy competition you have won Most Pompous Prick on this board - quite the achievement. now go do some yoga and see if the increased flexibility allows you to extract your bald head from your arsehole

this guy is really friendly and helped me out a great deal
and you only talk shit, baggytits
and hey, i see you've been voted Idiot#1 on this board, so whatever :lol: