TIMING ERROR

DRIFT IN MIDI SYNC

although here i describe a MIDI timing problen it could effect audio timing if the same clocking is used for both in N -

MIDI sync, no soundcard used, so internal timing used - the below has been tested and found to be ROCK SOLID when exactly the same thing is done in SONAR LE -

first i insert a MIDI track, MIDI track is at 120BPM and was recorded in N - track is sent to M$oft synth -

then i open the JAZZ MIDI Sequencer and insert the SAME track - track is sent to M$oft synth -

N is set to output MIDI Time Code to the Loopbe MIDI device -

Loopbe is an internal MIDI linker that allows two programs running on the same PC to connect together (no MIDI interface or wires required) -

JAZZ is set to recieve MTC that is sent from N via Loopbe -

so when i press play in N, Jazz starts at the same time, if i move the timeline in N, Jazz’s timeline responds to Ns commands - both N and Jazz are set to 25 frames per second -

OK, so here we have two MIDI programs that running together, both send their MIDI to the M$oft synth, if both are in sync then i should only hear 1 note at a time being played - this is the case in SONAR LE - BUT not in N -

in N both start exaxtly at the same place (single note heard) but as track plays MIDI notes drift apart and N stops playing well before Jazz has reached the end of the track –

if as said timing is ROCK SOLID when using SONAR LE as master sync out - then it is Ns timing that is at fault as here, Jazz is running as slave so is doing only what it is told to do -

to get the two to sync together i have to change the BPM in N from 120 to 16.5 - the MIDI track i used is quite short but after just a few seconds playing the drift is substantial -

now as i say here i am only concerned with MIDI sync, it could be that, (but unlikely) that N has teo clocks one for audio and one for MIDI - so if the same clock is used for both MIDI and audio timing then audio tracks will also suffer drift -

here is another problem - it has been said many times in this forum to always use WAVE (soundcard timing) for recording - but unless your soundcard has a CRYSTAL controlled clock on it it may well be using Windows clock to drive it so changing between wave and internal has no effect as they are (in this case) both the same - from my experience it is only the top of the range soundcards (the expensive ones) that have crystal controlled timing - if the soundcard has its own timing but that timing is not crystal controlled the the Windows clock may be more accurate -

Dr J

Hi Doc J:
You are on the “Cutting Edge” of getting DAWs to manage and construct Audio Files and Projects… by You…

I hope the DAW World and Flavio is watching and addressing your wants-and-concerns… according to how audio files are managed by DAWs…

Bill…