SYNC: BeatClock vs. MTC vs. SMPTE

I've been syncing the MPC to PTLE using MIDI Beat Clock (PTLE sending / MPC receiving.)

When I go back and look at the audio, I notice sometimes that certain drum hits or events are visibly (and sometimes audibly) off from the grid and the rest of the music.

I've never used any other kind of sync, and I don't even have the SMPTE chip for my MPC. I love the simplicity and ease of BeatClock, but am becoming skeptical about its accuracy.

I'm wondering how the other types of sync compare (MTC, SMPTE), and how accurate they are.........or any tips/tricks on how to make MBC more accurate?

Anyone? Anyone?

What midi interface are you using? try and check for the latest drivers. I had a lot of problems with USB midi interfaces and timing, but i've also seen some that work very well. I still use an old serial port midi interface and have better results there, but I think there may be some issues with software generating clock like that, not sure if it varies with different programs and what PT would have done with sync priority with LE, but try with clock from another program if you can. is there a way to sync PTLE to your xL? That might be better. SMPTE is pretty tight timing wise but somewhat of a hassle to use comparitively.
I guess I'm not much help but these things have so many variables that there has to be a way to get it working well with what you have.

id put my .02 in about the differences and advantages of each but I dont feel like typing that much. I will say that smpte will probably lock you up best though

a few things you can do to get a more accurate sync goin....

whenever recording always select 128 as your buffer size

in preferences go to the operation tab and in the Open Ended Record Allocation menu change "use all available space" to "limit to: 10 minutes" unless you need to continuously record for longer than that

is your computer optimized for PT? If not then you'll probably wanna do that

elmacaco wrote:What midi interface are you using?

I should have specified.

Mac G4 Sawtooth 400mhz
O/S 9.1
DIGI 001 MIDI/Audio interface (via SCSI port)
ProTools 5.1


PT will only send MBC, not recieve, so no hopes of going the other way around.

Is optimizing for PT possible on Mac? What does that involve?

meant to ask if you were on mac or pc.... Im on a pc but I found this for mac users..

http://www.bigbluelounge.com/forums/vie ... optimizing

i recently switched using the midi beat clocks from my 828 to a m-audio usb-midi....less conflicts/ timing issues

i'm guessing this has to do with the fact the FW bus is getting slammed and there is more bandwidth on the USB bus (kinda bass ackwards, huh?)


but smpte should be more accurate (according to the spec), but will force you to deal with smpte numbers........

that being said i've only used smpte to sync audio to video on nuendo, PT, and DP

very useful bcuz the video had a burn in window (cant miss)


anyone here syncing just audio via smpte??????

I think you are dealing with latency.
I think PTLE hardware does 256 ms off time.
I may be wrong, but if you do some digging at the Digi User Conference, you will find details.

Peace.

homershines wrote:I think you are dealing with latency.
I think PTLE hardware does 256 ms off time.
I may be wrong, but if you do some digging at the Digi User Conference, you will find details.

Peace.

The weird thing is though, that it's not consistently off for the duration of an entire track. Just certain drum hits here and there will be slightly off.....not the whole thing.

There is also midi delay as well.
You definitely need some real tight trouble shooting.
The answer may be simple, but I sure I was there to see and hear it.

Peace.

itchyvinyl wrote:

homershines wrote:I think you are dealing with latency.
I think PTLE hardware does 256 ms off time.
I may be wrong, but if you do some digging at the Digi User Conference, you will find details.

Peace.

The weird thing is though, that it's not consistently off for the duration of an entire track. Just certain drum hits here and there will be slightly off.....not the whole thing.

tempos the same in pt and on sequencer????

jaem wrote:
tempos the same in pt and on sequencer????

Yep.

The problem is more than likely software or driver realted.Specially if it sinks up at some points but not at others.Like maybe the computer is overloaded with info from the incoming audio.For sure fixable though your going to have to play around with some settings I would help but I don't use Mac's on regular basis.Try the digi user forums they are tons of help over there.

I honestly think its a bandwidth issue...

the bandwidth overload is just about maxed

if you can get ahold of another midi interface i would try that, see if it changes anything

your midi is at the mercy of the 001 (a scary thought, i know)

some OEM's dont do the greatest job integrating features within a given chipset

i have never used the midi (only audio) on a 001 so i cant say 100%

Be sure to turn off any "auto-run" programs on your computer....as others have pointed out, latency is probably the issue. Just like the MPC 4k ocassionally spins up the disk drive, your computer can have a number of programs running in the background without you knowing. If you stick a CD in the drive and it automatically runs, you need to turn this feature off. To see what is running in the background hit Control, Alt Delete one time. A list of active programs will be displayed in the pop up window. Turn off anything you are not using. RAM is cheap these days...install some more if you can afford it. On a side note - Beat clock is the worst - MTC is better - SMPTE even better yet - Blackburst is best....Long midi runs can occassionally cause a sync problem....When using MTC, try sending the MTC out on a dedicated channel. Recieving devices have to discard everything but the MTC to read it properly and this too can cause sync problems....IF you still have problems, just drop kick the danm thing...

He's using a Mac dude. There is no CTL-ALT-DLT!!