Noel Borthwick [Cakewalk]
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 19:05:38
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BTW if you still don't believe us and want to verify this further :-) you can download the source code to TWONAR from our DXi2 SDK to see exactly what its doing. Ron Kuper wrote that plugin so its not supported anymore - his home phone number is encrypted in the code though :-)
post edited by Noel Borthwick [Cakewalk] - 2007/10/19 19:18:01
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Noel Borthwick [Cakewalk]
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 19:11:30
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We use the standard Windows midiXXX API's to talk to MIDI drivers. User mode applications do not do any kernel mode processing.
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 19:18:56
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That's what I more or less have been assuming. So 1ms is the actual resolution of Sonar's midi, not 960ppqn, though it may be recorded in numbers on that timebase.
Yes?
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Noel Borthwick [Cakewalk]
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 19:39:26
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The MIDI API sends the timestamp at a 1ms resolution via the midiIn device callback.
During MIDI recording incoming data is queued up at millisecond resolution and then converted to the 960 tick resolution for storage in tracks.
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Jim Wright
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 19:50:04
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ORIGINAL: Noel Borthwick [Cakewalk]
The MIDI API sends the timestamp at a 1ms resolution via the midiIn device callback.
During MIDI recording incoming data is queued up at millisecond resolution and then converted to the 960 tick resolution for storage in tracks.
Thanks, Noel. That seems pretty definitive to me! - Jim
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 20:02:38
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Thanks Noel for the clarifiations!
Ok, given that Sonar is hardwired to record midi events at a timer resolution of 1ms, stored with values at a 960 timebase, I think Steve's operating method does make absolute sense to get closest to what is actually happening in the hardware, given that we have no control over the actual timer resolution used.
The reason is because the 1ms intervals do not necessarily land evenly on 960PPQN tick intervals. In fact it completely depends on the tempo. This does not mean that anyone is getting sub-millisecond timing. Nobody is. The best you can expect is 1ms. But, because of the MM timer and the midi clock timer not necessarily being synchronized, errors can result there too which might cause a little jitter right around 1ms.
For example:
At 120BPM, 1ms = 1.92 ticks
When the MM timer goes to get whatever is in the midi buffer, all the midi events that have been received within the past ms are given a timestamp to the same tick. They are going to be rounded off to the nearest tick.
at 180BPM, 1ms = 2.88 ticks. You see the advantage? When rounding off to the nearest tick, there are more ticks to choose from for the rounding. A higher tempo gives you better rounding to the nearest tick essentially.
I suppose if you wanted, you could figure out which Tempos would theoretically provide no rounding errors at all, but its a bit moot since the MM timer is not guaranteed to be in sync with the midi clock ticks, nor is the MM timer that accurate, so eliminating as much as possible the rounding errors seems to be the best bet here, combined with using the best midi interface you can find, preferably not USB.
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 20:30:36
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Noel, As I sit here thinking about it... I think it makes no sense for Sonar to timestamp to 960PPQN. If that is a hardwired resolution or rather should I say, if sonar is going to be hardwired internally to record and play back events at some resolution, doesn't it make more sense to use a larger timebase to get less rounding errors? Then Steve doesn't have to use insanely huge tempos to accomplish the same thing. Ehhh........., never mind. I find the current resolution just fine. I don't really want to look at 4 digits of resolution in all my various midi edit widgets just to avoid some small amount of rounding jitter +/- around 1ms. At some point we're splitting hairs. I just switched my USB controller off and am using the midi-out into my parallel-port MOTU interface and can feel a noticeable difference while playing piano. I really think avoiding USB midi is key for discerning people. Given that Sonar always uses the 1ms timer, I see zero advantage to using lower PPQN than 960.
post edited by dewdman42 - 2007/10/19 21:37:25
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brundlefly
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 21:37:28
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I just ran through your test, and it definitely looks like what you're seeing is introduced by TTS-1. I was able to reproduce your results, although the variations in the spacing of the hits were extremely regular in my test. Thanks for looking into this, Dave. My test also found the pattern you're seeing, mentioned in an earlier post. Namely groups of three or four intervals that were a little too long, followed by a very short one that would put the net timing close to being back on track. Testing of the TruePianos VSTi seemed to confirm that any timing issues were a product of the synth itself, and not Sonar, as TruePianos was very consistent and accurate in it's reproduction of event timing. If the TTS-1 could be improved, that would be great, but it's certainly quite usable as it is. I undertook this investigation more out of curiosity than concern about timing accuracy.
post edited by brundlefly - 2007/10/19 22:10:54
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:21:55
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ORIGINAL: Dave Malaguti [Cakewalk]
I just ran through your test, and it definitely looks like what you're seeing is introduced by TTS-1. I was able to reproduce your results, although the variations in the spacing of the hits were extremely regular in my test. (Emphasis added - RTG)
Interesting. TTS-1 still contains Roland technology, yes? I'm really curious to go dig up my old timing test results from the TR-505 drum machine, and see if there's any correlation between TTS-1's timing anomalies and the TR-505's deliberately skewed sixteenth note quantization. My work schedule is extremely intense, and that info was on an old machine, but if I can find it I'll post it.
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:26:26
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ORIGINAL: dewdman42
Ideally, Microsoft would mimic Apple and license MOTU's MTS. That way, all the MOTU hardware would instantly become useable under Windows sequencers that use the new model.
Actually, I'm thinking even more broadly. Microsoft should build an API that incorporates a similar feature, and then that should become a standard for all MIDI interface manufacturers to use. I don't want to be limited to just MOTU products - their Windows support is still sub-par, in my experience. In theory, there may be manufacturers whose interfaces already have the internal capability to support hardware timestamping, and those interfaces would be "upgradable" to the new standard through a driver update.
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Jim Wright
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:29:11
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The reason is because the 1ms intervals do not necessarily land evenly on 960PPQN tick intervals. In fact it completely depends on the tempo. This does not mean that anyone is getting sub-millisecond timing. Nobody is. The best you can expect is 1ms. But, because of the MM timer and the midi clock timer not necessarily being synchronized, errors can result there too which might cause a little jitter right around 1ms. Yes. Makes sense to me.
I just switched my USB controller off and am using the midi-out into my parallel-port MOTU interface and can feel a noticeable difference while playing piano. I really think avoiding USB midi is key for discerning people. Given that Sonar always uses the 1ms timer, I see zero advantage to using lower PPQN than 960.
I think that's pretty telling -- at least for your particular system  I'd like to sum up some conclusions I think we've arrived at, through the course of this 13 page (!) thread: - Sonar's performance, as far as MIDI jitter is concerned -- is at least as good as any Windows app we know of.
- If you're concerned about MIDI jitter, a parallel-port or PCI-based MIDI interface should give the best results.
Avoid USB MIDI interfaces**. (The verdict on Firewire interfaces is not yet in)
** Some USB MIDI interfaces may have relatively good timing - but look for clear test results that show it.
- Soft-synths, if written poorly, can have really lousy MIDI jitter. That is not Sonar's fault.
- Soft-synths, if written well, can have sample-accurate MIDI timing. Sonar gives those soft-synths what they need in order to deliver the goods.
- 960 PPQN resolution is a good thing. Use it.
- A mis-configured system (or one with a number of different MIDI interface drivers) can produce driver conflicts that do bad things to MIDI timing. This one is based on personal experience, and also on reports from at least one user with 5! MIDI interfaces.
- The built-in metronome, for some people, has been associated with timing problems.
For details and workarounds, see http://forum.cakewalk.com/fb.asp?m=1191679, below (post #379, by dewdman42).
I'm offering these conclusions partly so that the key points we've concluded are all in one place -- and also so that, hopefully, nobody will use this thread for Sonar-bashing purposes. I think Sonar is great. I've been a bit concerned this thread might have raised some eyebrows, given that a new Sonar release (with tons of MIDI improvements) has just shipped. I think we now have a better handle on the kind of performance Sonar can deliver, and things people can try if their system is not doing what it should. Just my 2 bits -- YMMV, as always. Jim Edited to add metronome bullet.
post edited by Jim Wright - 2007/10/20 11:35:35
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:29:28
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ORIGINAL: dewdman42
If you have 2-4ms of slop when recording your midi parts, then it does not matter what the resolution is set to..it only means it will record the slop more precisely... more precisely recorded slop! heh heh.. Its futile to think its giving any more accurate precision than that. and there is the possibility that the increased work load going to the computer to handle more ticks per second will make the slop worse.
Point well taken, but there are still benefits to using 960ppqn resolution, especially given the current proliferation of softsynths. Granted, MIDI data coming in from, or going out to, external devices won't benefit from the increased resolution, but softsynths rendered internally to the application will... and that means that 960ppqn resolution gives more precise editing options. It means that if I'm tweaking a BFD drum performance, whether that performance originated on a set o V-Drums, a keyboard or a prerecorded MIDI groove, I have that much finer control over where the drum hits will ultimately sound, and therefore the way the performance feels.
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:29:30
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ORIGINAL: RTGraham
Actually, I'm thinking even more broadly. Microsoft should build an API that incorporates a similar feature, and then that should become a standard for all MIDI interface manufacturers to use. I don't want to be limited to just MOTU products - their Windows support is still sub-par, in my experience. In theory, there may be manufacturers whose interfaces already have the internal capability to support hardware timestamping, and those interfaces would be "upgradable" to the new standard through a driver update.
There is nothing limiting anyone right now from building hardware interfaces that are compatible with Apple's CoreMidi (which is MOTU's MTS). What I'm suggesting is that if the same technology is used for windows, then midi manufactures can build midi interfaces that would work with both CoreMidi and whatever MS builds...anyone could build it...and there would already be some MOTU interfaces in existence that would work out of the gate.
post edited by dewdman42 - 2007/10/19 22:44:06
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:30:55
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ORIGINAL: dewdman42
There is nothing limiting anyone right now from building hardware interfaces that are compatible with Apple's coreMidi (which is MOTU's MTS). What i'm suggesting is that if the same technology is used for windows, then midi manufactures can build midi interfaces taht would work with both CoreMidi and whatever MS builds...anyone could build it...and there would already be some MOTU interfaces in existence that would work out of the gate.
Got it.
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:33:49
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ORIGINAL: Jim Wright
I'd like to sum up some conclusions I think we've arrived at, through the course of this 13 page (!) thread...
...
...
I'm offering these conclusions partly so that the key points we've concluded are all in one place -- and also so that, hopefully, nobody will use this thread for Sonar-bashing purposes. I think Sonar is great. I've been a bit concerned this thread might have raised some eyebrows, given that a new Sonar release (with tons of MIDI improvements) has just shipped. I think we now have a better handle on the kind of performance Sonar can deliver, and things people can try if their system is not doing what it should.
Nice summary, Jim. And a good point, that we don't want to portray SONAR as having problems - quite the opposite, rather: we're pinpointing system-wide, industry-wide limitations. And thankfully, it seems that we're all managing to get on the same "page." (after 13 of them! )
~~~~~~~~~~ Russell T. Graham Keys, Vocals, Songwriting, Production russell DOT graham AT rtgproductions DOT com www DOT myspace DOT com SLASH russelltgraham
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:35:42
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I agree, nice summary. I can't think of anything else to add, except for perhaps a comment about some known audio metronome problems which sometimes afflict people in Sonar in ways that can sound like midi timing errors.
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Jim Wright
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:40:33
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ORIGINAL: RTGraham
ORIGINAL: dewdman42
Ideally, Microsoft would mimic Apple and license MOTU's MTS. That way, all the MOTU hardware would instantly become useable under Windows sequencers that use the new model.
Actually, I'm thinking even more broadly. Microsoft should build an API that incorporates a similar feature, and then that should become a standard for all MIDI interface manufacturers to use. I don't want to be limited to just MOTU products - their Windows support is still sub-par, in my experience. In theory, there may be manufacturers whose interfaces already have the internal capability to support hardware timestamping, and those interfaces would be "upgradable" to the new standard through a driver update.
Ideally, we would develop some new technology for MIDI interfaces, that would provide far better timing for MIDI-DIN input and output without overly burdening the host computer (or costing an arm, leg and torso). I know I'm being kind of a tease here - but if someone with some hardware chops (preferably FPGA design) wants to collaborate, let me know (jim period wright aaattt acm period org should reach me). I had a brainstorm a few years back, and it's itchin' something fierce - Jim
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Jim Wright
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:42:56
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ORIGINAL: dewdman42
I agree, nice summary. I can't think of anything else to add, except for perhaps a comment about some known audio metronome problems which sometimes afflict people in Sonar in ways that can sound like midi timing errors.
Good catch! Please suggest some concise language (you're more familiar with metronome does and don'ts than I am) and I will edit my post accordingly. - Jim
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:49:29
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Just that there are some scattered reports from people having wierd timing problems related to the audio metronome. Including me. This year I had a project, only a few tracks and it would start out fine but after working a while the timing started getting all messed up. I couldn't figure it out. Then I looked around on this forum and found other people with similar issues and it was related to the audio metronome. When I routed metronome to midi instead of using Audio, the problem disappeared. It seems this is some kind of wierd bug that comes up for some people. I have heard a few possible work around suggestions: - Route the metronome to midi and use a soundsource like Session Drummer 2 - Record a quantized one bar metronome midi pattern, convert it to groove, put it on a midi track, playing through Session Drummer2. - In the metronome setting (project options), send the audio metronome to a buss instead of directly to the hardware audio port which is the default. - Here is a suggestion that looks very good too, which involves setting up a metronome audio track or set of audio tracks that output sample accurate metronome output: http://forum.cakewalk.com/fb.asp?m=1192305 I can't remember what I did to move foward at the time, I think I just turned off the metronome and did what I need to do. Never had the problem come up again. I only mention it because someone trying to troubleshoot their midi timing errors needs to be aware of this possibility and rule it out from their scenario just in case.
post edited by dewdman42 - 2007/10/20 19:09:15
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pianodano
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RE: MIDI "Jitter" - It Does Exist
2007/10/19 22:56:37
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Dewdman42, RE: doubling (or more) tempo to simulate increased resolution, Yep Roland recommended that way back in 1987 for the MC500mkII. This is has been a good learning experience for me. You guys seem to have a real understanding of the challenges in making it work correctly,reliably, accurately (choose one) for critical listeners and discerning users, on a pc. At the risk of a total flameout, (and to summarize what is starting to gel now in my twisted mind). It seems reasonable (to me) to assume, that at the present time, it's as good as it's gonna get. IF that is the case, it seems to me that based on the joyful noises, glee and downright exuberation exibited by untold numbers of users everywhere, that there must be many zillions of happy campers out there that are not even aware that "Houston we sorta have a problem". OR, perhaps they don't expect anything better ? OR even, (and I wince) they can't tell ? Gulp! Dang. Although I hesitate to really believe that, some part must ring true because I have seen quite a few concerned individuals shark attacked by many of them thar happy campers in the past for their efforts at trying to discuss and understand just what the heck is going on. On a side note, if most of this is true, that must explain why I don't listen to the radio much any more.  Also thank you Jim for sharing some of your exceptional knowledge on this subject.
post edited by pianodano - 2007/10/19 23:27:23
Best, Danny Core I7, win XP pro, 3 gig ram, 3 drives- Lynx Aurora firewire- Roll around 27 inch monitor, 42 inch console monitor- Motif xs controller - Networked P4's and FX Teleport for samples- Muse Receptor VIA Uniwire for samples and plugs- UAD QUAD Neve - UAD 1- Sonar X1 but favor 8.5 GUI - Toft ATB 32 - Vintage hardware - Tascam MS-16 synched via Timeline Microlynx -Toft ATB32 console
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 00:14:34
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ORIGINAL: pianodano
On a side note, if most of this is true, that must explain why I don't listen to the radio much any more.
Naw, everything on the radio is already quantized anyhow. <Big Grin> ORIGINAL: pianodano
Also thank you Jim for sharing some of your exceptional knowledge on this subject.
I'll second that.
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Nick P
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 02:19:57
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Guys, what a great thread! Now that we've heard from Noel and Dave, we have official company statements on this issue, along with numerical data supporting the evidence. Thus, assuming we trust their statements and data, which I do, we can conclude that (drum roll) Sonar is able to accurately record, process and playback MIDI data. Now making this happen on a practical level might take a bit of tweaking, but at least we can be reasonably sure that Sonar itself is not causing MIDI "jitter". (This begs the question: what is Ableton talking about, then?)
This thread, which has morphed into sort of a "white paper", will be transcribed and saved in my Sonar information file.
In the meantime, regarding USB-MIDI interfaces, will someone please comment on the suitability of the M-Audio USB Midisport Duo. That's what I use for my 88 note MIDI keyboard. Also, if USB is not the best choice for accurate MIDI recording, how does that square with the hundreds of USB-MIDI controllers on the market. For example, I have the (reasonably new) Edirol PCR-800. Are you guys saying this shouldn't be used to record accurate un-quantized MIDI because it's USB?
Finally, I'm glad the clock resolution thing seems to have been resolved. If I'm understanding Noel and Dave correctly, no matter what res you set the clock at, Sonar is going to read and write from the Windows API at 960PPQ. So there is no basis to a lower clock setting yielding better MIDI performance. Good. Another thing not to have to worry about.
So one more time, in considering the impetus I had to start this thread, what is Ableton talking about? How are they "improving" MIDI performance with Live 7?
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dstrenz
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 06:31:28
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ORIGINAL: RTGraham
ORIGINAL: pianodano
Also thank you Jim for sharing some of your exceptional knowledge on this subject.
I'll second that.
I'll third that and have learned more about midi implementation on PCs from this thread that I could have anywhere else in the same amount of time.
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dstrenz
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 06:33:56
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ORIGINAL: Nick P
So one more time, in considering the impetus I had to start this thread, what is Ableton talking about? How are they "improving" MIDI performance with Live 7?
They're the only ones that can answer that. For all we know, they merely tightened up their own midi implementation and/or fixed some bugs or faulty logic.
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Jim Wright
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 12:18:41
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Hi Nick, 1. Re: USB MIDI interfaces USB MIDI interfaces cannot perform quite as well as PCI or parallel-port interfaces (assuming all interfaces have decent drivers, etc.). Why? USB MIDI adds at least 1-2 milliseconds of jitter on top of the "baseline" jitter resulting from the use of the 1 millisecond Windows "MM" timer used for timestamping MIDI data. See http://forum.cakewalk.com/fb.asp?m=1191358 for more detail about where jitter comes from. See http://forum.cakewalk.com/fb.asp?m=1186189 and http://forum.cakewalk.com/fb.asp?m=1186298 for some recent non-scientific timing tests I ran, on several MIDI interfaces I own. It's very clear that my USB MIDI products (Edirol UM550 interface, M-Audio Axiom 61 with built-in interface) have about 2 milliseconds more jitter than my EMU 1820M PCI card (with 2 MIDI ports). So, for timing-critical parts, I will use the MIDI-DIN outputs of my Axiom 61, connected to the MIDI-DIN ports on my EMU PCI card. Use your ears. If you are happy with the results you get from your USB MIDI controller (or interface) -- great! Don't let us mess with your mind! If you're concerned - try a different kind of interface (PCI or parallel-port recommended; Firewire should also work better than USB MIDI, but I haven't tested that). 2. >> "Also, if USB is not the best choice for accurate MIDI recording, how does that square with the hundreds of USB-MIDI controllers on the market." Most people don't notice the difference. USB MIDI is dirt-cheap, compared to other alternatives. Microsoft changed Windows in ways that made it harder to do parallel-port or PCI MIDI interfaces. Hooking up a USB cable is easier (and less risky) than installing a new PCI card. Modern motherboards have fewer PCI slots..... there are lots of reasons why the market has gone towards USB MIDI. Market realities dictate that many companies have to use USB MIDI, regardless of whether it's the "best" solution or not. It may be worth noting, again, that the MMA has endorsed Firewire MIDI (I edited that spec, actually;it's linked from the MMA website) - but the MMA has never endorsed USB MIDI. Since lots of MMA members make USB MIDI products, this interesting fact doesn't tend to get much press. In fairness, I should also note that current USB MIDI interfaces perform a lot better than they did circa 2000 (7+ milliseconds of jitter, always, with occasional spikes well above that -- puh-leeeze!). The MMA might well decide to endorse USB MIDI today, because it's improved a lot, and is usable. My two cents; YMMV. 3. Re: "What is Ableton talking about?" As dstrenz said - you'd have to ask them. My guess is that they had some sloppy code in older versions of Live, decided to clean it up, and decided to turn a bugfix into a marketing advantage. It's also possible (barely) that Live 7 includes a kernel-level event engine with < 1 millisecond jitter (see my first linked post above for a ramble about kernel-level stuff ..... but also note that performance with USB MIDI interfaces would not be improved much/at all by a kernel-level engine, because the 1-2 millisecond jitter of USB MIDI would "swamp out" any benefits of a kernel-level engine -- because jitter is additive.) Their marketing claims really don't tell us anything about whether Live 7 is better or worse than Sonar 7 wr..t. MIDI timing. We just don't know. We'll have to wait for Live 7 to ship, and for someone to do some credible testing. I really do like the idea of companies publishing a "MIDI Engine FactSheet". Here's what Ableton has promised to do, for Live 7: MIDI Engine Fact Sheet
The MIDI Engine Fact Sheet documents MIDI timing tests on both Windows and Mac platforms using various MIDI interfaces and describes exactly what users can expect in terms of MIDI timing accuracy. Coming Soon. I wish Cakewalk would publish a similar document. - Jim, MIDI curmudgeon
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Jim Wright
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 12:28:15
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dewdman42 - I've edited my 'conclusions' post to add a bullet about metronome issues. It has a link to your post ( http://forum.cakewalk.com/fb.asp?m=1191679) for details/workarounds --- it would have been silly to rewrite what you had written so clearly. - Jim
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RTGraham
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 15:59:50
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ORIGINAL: dstrenz
ORIGINAL: Nick P
So one more time, in considering the impetus I had to start this thread, what is Ableton talking about? How are they "improving" MIDI performance with Live 7?
They're the only ones that can answer that. For all we know, they merely tightened up their own midi implementation and/or fixed some bugs or faulty logic.
Er, wouldn't that be faulty "Live-ic"? "Living"? Never mind. I just hate to see this thread fade into obscurity, as all threads inevitably do, when it has become so comprehensive and informative, and especially if there's a chance that it can influence the industry moving forward. Sticky, anyone?
~~~~~~~~~~ Russell T. Graham Keys, Vocals, Songwriting, Production russell DOT graham AT rtgproductions DOT com www DOT myspace DOT com SLASH russelltgraham
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Steve_Karl
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 16:10:43
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dewdman42
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 18:56:15
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Steve, great tip. That looks like the best work-around to me in terms of accuracy for sure. I like it.
one question, does anyone know what exactly is this "metronome buss"?
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Steve_Karl
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RE: MIDI "Jitter" - It Does Exist
2007/10/20 19:06:45
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In my work around the "metronome buss" is just a normal audio sub that I route the individual audio click tracks to.
The tracks being the ones that have the clicks on them as audio slices.
In one project I used 7 different tracks with volume envelopes on them so I could gently move between a 4/4 and 3/4 feel by adjusting the envelopes. At times both feels were audible.
The object of this was to have that same type of feeling in the music, i.e. playing in 3/4 but also having a 4/4 feel encompasing it.
An other cool feature of the way I'm using it is that I have the Volume for that buss and the Mute for that buss both "learned" by 2 controllers on my S90 keyboard.
So I can turn the metronome on an off and also adjust it's volume from my keyboard while I'm cutting tracks.
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