Drop outs when [b]recording[/b] in Vegas Audio 2.0g

philokeefe wrote on 9/7/2001, 6:36 PM
Hi everyone... I'm getting some serious drop outs with my Vegas Audio 2.0g (build 415) setup. It doesn't happen all the time, but about 50% of the time, it will drop out for a second or two while recording... instead of getting one continuous set of recorded tracks, it will "gap" and have blank spaces between the parts that actually recorded and multiple "takes" show up in my default .WAV storage folder.

I'm using a Frontier Designs Dakota / Montana card setup. I have its settings set up to get W/C (word clock) from the incoming lightpipe signal (coming from my Yamaha mixer) and Vegas is set up to get MTC from my mixer ... the MTC is coming into either my Dakota's MIDI input or my MOTU Micro Express MIDI interface (both setups give similar results as far as the occurance of gaps while recording). Vegas is set to get the audio from the lightpipe inputs on the Dakota, which as I've already mentioned, is set to get the W/C from the incoming lightpipe (this is set in the Dakota systray applet), so I don't think this is a W/C problem...

Computer system is a 933 MHz PIII with 384 MB RAM, and two 7,200 RPM HDD's - one dedicated for audio recording only (D drive) and both drives are DMA, and set accordingly in Windows (98 SE BTW).

I have not had any problems whatsoever with audio playback gapping or dropouts... just when recording. I've been recording 16 tracks at a time, and CPU, Disk and RAM meters in Vegas hardly show any use at all... I also get the problem when I try to record with fewer tracks...

Any suggestions or help would be greatly appreciated!

Thanks




Phil O'Keefe
Sound Sanctuary Recording
Riverside CA
http://members.aol.com/ssanctuary/index.html
email: pokeefe777@msn.com

Comments

pwppch wrote on 9/7/2001, 7:49 PM
It sounds like the MTC is dropping and causing Vegas to start and stop.

You might try raising the freewheel time for MTC. Also, make sure that you have Vegas set up to trigger to MTC.

Peter




philokeefe wrote on 9/7/2001, 10:46 PM
Thanks for the quick response!


It sounds like the MTC is dropping and causing Vegas to start and stop.

TRIGGER to MTC instead of sync to MTC? It seems like I might get drift that way... I do know how to change this, so I'll try it and see what happens. BUT, I am not sure how to change the freewheel time for recording... is that the "Freewheel slack time" in the Preferences/Sync/Advanced dialog box?

Here's how everything's set in Vegas as of right now.

Preferences/Sync/Advanced:

"Freewheel for T/C loss" box checked.
Freewheel slack time: 0.200
Freewheel Playback Time: 2.000 seconds
Sync Delay Time: 2.000 Seconds

Specific suggestions on changes to this (or whatever areas needed) would be greatly appreciated!

Thanks again for your help Peter, I really appreciate it. This is a great program, but it's annoying when it drops out in recording...especially when I have a client looking over my shoulder... :)



Phil O'Keefe
Sound Sanctuary Recording
Riverside CA
http://members.aol.com/ssanctuary/index.html
email: pokeefe777@msn.com

PipelineAudio wrote on 9/7/2001, 11:03 PM
Phil what are you doing in here? Didnt know you were a Vegas user! :)

Aaron Carey from RO

If you look way back in the forums, I had a lot of trouble recording in sync. There was a lot of stuff back and forth, but I took Peter's advice and
set it to only trigger from MTC...worked out great.
Just to see how far off it got ( I thought it would stray VERY far) I ran it alongside the tape track, and it was still close enough ro cause phase cancellation, so you should be fine.

Rednroll wrote on 9/8/2001, 5:53 PM
One trouble shooting word of advice that I have, when dealing with syncing issues, is to reverse which device is the master and what device is chasing. I'm having a little trouble following your studio setup, since you say you have Vegas chasing MTC coming from your yamaha mixer? Your mixer generates MTC? I know i must be misunderstanding something, since I don't know any mixer that generates MTC, just receives. Anyway, try setting Vegas to be the master and have your mixer and your micro express...and sequencer if that's what is connected to the micro set to external sync. It's usually best to make your recording device (ie Vegas) the master clock and have the other devices chase its MTC, than vice-versa.

Good luck
pwppch wrote on 9/8/2001, 6:09 PM
Since you are using a common Word clock, then trigger is all you need.

FYI: Chasing (vs triggering) cause Vegas to constantly resample the playback audio in order to 'chase' to the incomming clock. This is EXPENSIVE.

Peter



pwppch wrote on 9/8/2001, 6:10 PM
Good advice!

When recording, if at all possible, set Vegas as the master. This way the task of staying in sync is the problem of the other non-recording boxes.

Peter
philokeefe wrote on 9/8/2001, 7:48 PM
Yes, I've been using Vegas for some time now for audio only editing needs. I still use LAP 4.7 for Midi / audio needs, but for audio only, I find Vegas to be much easier and faster.



Phil O'Keefe
Sound Sanctuary Recording
Riverside CA
http://members.aol.com/ssanctuary/index.html
email: pokeefe777@msn.com
philokeefe wrote on 9/8/2001, 8:24 PM
>>>One trouble shooting word of advice that I have, when dealing with syncing issues, is to reverse which device is the master and what device is chasing. I'm having a little trouble following your studio setup, since you say you have Vegas chasing MTC coming from your yamaha mixer? Your mixer generates MTC? I know i must be misunderstanding something, since I don't know any mixer that generates MTC, just receives. Anyway, try setting Vegas to be the master and have your mixer and your micro express...and sequencer if that's what is connected to the micro set to external sync. It's usually best to make your recording device (ie Vegas) the master clock and have the other devices chase its MTC, than vice-versa.

Good luck


Thanks for the suggestions and the reply!

Okay, "mixer" wasn't really the right term to use, but that's the paradigm I use when thinking of my dual Yamaha AW4416 setup. And yes, they do generate MTC and W/C, as well as slave to either / both. But the problem is that I'm running two of them, digitally cascaded, and for reasons I won't get into here, it's just plain easier to have the computer chase rather than to go the other way.

Sure, it's nice to set up the computer as MTC / MMC master, but there's cases where it's the obvious choice for the slave (ie locking to an ADAT system or ATR).

But the good new is that it looks like I've solved the problem.... it wasn't my computer or Vegas, it was my MOTU interface. And just in case anyone else runs into similar problems and is searching the forum at a later date I'm going to explain it in some detail.

Apparently, the MOTU Micro Express MIDI interface "swallows" (MOTU's term, per their manual) incoming MTC... you have to use their sync port in software to route it to where ever you want it to go... which is what I was doing, but it took 7+ seconds for lockup and (apparently) isn't as stable as MOTU might want us to believe.

I tried HARDWIRE routing the MTC cable from the AW4416's to the MIDI in on my Dakota card (instead of doing it through the MOTU patching applet as I had it previously set up) and set the Dakota systray applet to get W/C from one of the incoming lightpipe cables (one AW4416 is serving as the W/C master for the whole system) and MTC from the incoming MIDI cable on the Dakota's MIDI port... and also set the applet up to route that MTC to software.

Then I set Vegas to:

Chase to MTC: Dakota 1
Frame Rate: 30 FPS / ND

Advanced:

Freewheel for T/C loss: Checked
Slack Time: 0.200
Freewheel Playback time: 2.000 sec.
Sync Delay: 2.000 sec.

...and everything works great! Added benefit: Lockup times are now in the 2 - 3 second range, which is about as fast as my AW4416's lock to each other.

Just for the record, as a test, I'm transferring 16 tracks into Vegas on this machine (while I'm also on the Internet on the SAME MACHINE typing this...) and was able to do both tasks at the same time... 5 minutes of 16 track / 24 Bit / 48 KHz audio transferred without any problems whatsoever while to computer was also logged on to the internet (external 56K modem) and had three IE 5 windows open.

Now my only remaining question is this:

Would I get better results (for whatever reason... more plug ins, et cetera) if I used the "Trigger Playback Only" option in the Advanced dialog box instead of "Freewheel For T/C Loss"? And, from the names used here in the advanced dialog box, I'd almost assume that this is only relevant for playback and not while recording.... is this true?

With my Dakota (which is performing true Hardware based chase lock) I'd imagine I'd be okay with just trigger in Vegas and not have to worry about drift... Does that sound about right?

Thanks to everyone for all the help. I'm feeling (and my system is running) much better now, and if can just settle these drift / trigger / chase lock questions / options in my own mind I'll be all set.



Phil O'Keefe
Sound Sanctuary Recording
Riverside CA
http://members.aol.com/ssanctuary/index.html
email: pokeefe777@msn.com



philokeefe wrote on 9/8/2001, 8:32 PM
Peter, please see my other (newest) long post in this thread... I solved the problem (traced it to problems within the MOTU interface - unstable MTC!) and I had a couple more questions regarding the MTC chase vs trigger... since I'm running a Dakota and it would seem I now have it set to do actual hardware based (on the Dakota card) chase lock, trigger would be all I need.... but I want to make sure drift won't be any worse if I select that option in Vegas.

Thanks again for all your help... I was a bit converned with SF's customer support options, but it's nice to see my worries were unfounded and that a SF rep addresses questions so quickly and in such a helpful manner. Tell your boss to give you a raise... :^)



Phil O'Keefe
Sound Sanctuary Recording
Riverside CA
http://members.aol.com/ssanctuary/index.html
email: pokeefe777@msn.com
Rednroll wrote on 9/9/2001, 9:36 PM
An LAP user huh? You are a brave person, I have a copy of LAP 4.0 on my system and that program scares the hell out of me everytime I open it and try to do a simple task like record a midi track or audio track. I consider myself to be well versed in many audio programs Mac or PC, and I just don't understand how that program works. I heard once Opcode died many users switched to LAP, I gave it a whirl and couldn't handle the learning curve....guess I had work to do. I did read that LAP was going to work on it's user interface and try to be more like Opcodes studio vision, since so many users came over from opcode. Has it improved any since my v4.0 that I have?

Hey Sonic Foundry guys, I think a great idea for the next Acid release....seeing that you ventured into the midi tracks feature in 3.0, is to study Opcodes Studio Vision user interface and incorporate that into Acid.....Then you would have the best preproduction program ever made. For now, I still have a computer in my studio that just runs Vision for my midi needs.

philokeefe wrote on 9/10/2001, 8:45 PM
Well, I'm not sure I'd want it based on Studio Vision's model, but I'm definitely interested in a version of Vegas with full blown MIDI sequencing (not just midi file playback) capabilities.

Logic's NOT an easy program to use... but the learning curve was shallower for me since I've used their stuff since 1988 and the Notator days... It's an amazingly powerful sequencer, but let's face it - Vegas is MUCH easier to use for audio only needs. Logic is currently at version 4.7, so the overall "feel" and interface isn't any different than when you used 4.0. 5.0 WAS due to be released in September (this month) but has been pushed back to January 2002. The new "audio / MIDI engine" has been implemented into 4.7, but that has no real bearing on the user interface. Maybe they'll improve it in 5.0, but who knows? I really don't care either way. This is, after all, a SF forum... and if I have a choice (ie: audio only project sans MIDI) I'll use Vegas just about every time. It's faster and easier, and while the Logic Environment (area of the program) is extremely powerful and can be fully user configured and modified, it's just too hard for most users to "get" - even some very experienced ones.




Phil O'Keefe
Sound Sanctuary Recording
Riverside CA
http://members.aol.com/ssanctuary/index.html
email: pokeefe777@msn.com