PlanetZ forums - scopeusers.com

Well I've finally started doing some final mixes of stuff and I'm having huge problems. My system is:

Mac G4 500MHz SP, OS9.0.4
768Mb RAM , 18Gb HD
Pulsar2 Plus & Scope SRB, Pulsar v3.01
Cubase VST32 v5.1r1
Midex3, Griffin Audio USB hub

with all the usual Apple tweaks.

What is happening is everything is fine in playback, with say 16 or less tracks of audio, not all playing at the same time, perhaps one VST instrument playing live (M-Tron), audio is bussed to PulsarMixer, with Optimaster on master insert, then Mix out to ASIO in. As soon as I try to record this mix to stereo in the Arrangement it all goes Pete Tong. There are some very nasty pops and crackles to be had. I record at 24bit 44.1kHz.

I've tried changing ULLI (I usually work at 7ms) - with a higher latency (13ms) the pops disappear but all my MIDI starts to fall apart timing-wise. At a lower ULLI setting (4ms) timing is spot on but the crackles get worse. The MIDI is only triggering M-Tron, STS and a couple of Pulsar synths, nothing external via the Midex. I tried switching VST sync from Internal to ASIO2 with no effect. Also Favour MIDI Timing has no effect. I've been so happy with Pulsar and Mac and now that I come to the crunch it isn't working. Also, I've done three other final mixes of more complex tracks and those came out OK and I can't see any difference in settings for those (I think I set ULLI at 13ms for these and MIDI was tight, and no pops).

Any ideas appreciated,

Tony R

PS. I will soon be upgrading OS to 9.2.2 and SFP3.1c, but I don't think that will really help with this problem.


<font size=-1>[ This Message was edited by: TonyR on 2002-11-05 09:15 ]</font>

<font size=-1>[ This Message was edited by: TonyR on 2002-11-05 09:17 ]</font>

I don't no what can be the reason of your problem, but I think you should do the SFP upgrade job.
It'll give you a fair chance you solve your problem, coz it's stable and nice on Mac.
(You can keep your current 3.01 version on disk, there is more info on planetz about this, try a seach).
Hope someone else can help you better!

Update your system to 9.2.2, too - it really helps in almost all purposes (faster SFP GUI, more stabile etc). SFP 3.1c + 9.2.2 is a nice combination (ULLI at 4ms/44.1kHz on G4/400 AGP). And (if you haven't done it already) connect your Midex directly to the computer socket (with no hub between). Also try (this sometimes helps) trashing the Multiprocessing folder found in your extensions folder (do it manually - it's invisible for Extension Manager). And at the end: look at http://www.planetz.com/forums/viewtopic ... 3&forum=19 .

Oh, and one more: disable all schedules in Sherlock (no disk indexing!)

<font size=-1>[ This Message was edited by: samplaire on 2002-11-06 03:38 ]</font>

I forgot about something: get rid of AirPort extensions/control panels if you don't have one.

I will upgrade to OS9.2.2 and SFP 3.1c this weekend (hopefully) and I'll tell you if it improves things. Do any of you VST users know if Synchronization should be set to Internal or ASIO2? It didn't seem to make any difference, but I would like to know the theory behind this as the documentation for this is a little vague.

Also, I didn't mention that a couple of times whilst trying to master I got a PCI overflow error (which I've never had during tracking) so I'm thinking this is more of a VST problem than a Pulsar one.

Do you think it would be better to record my VST instruments onto another track, thereby freeing the Mac processor of a VSTi, but increasing the number of audio tracks to be replayed?

Tony R

About synchronization: I don't know much about it but I've heard that midex is very accurate with cubase.

Yes, VST instruments can push your system to overload (watch cubase performance). I don't know if it affects mixdowns - in my arrangements it is normal that 2/3 of system load and beyond causes cubase to be less stabile (crackles etc). So I think the above optimizations can improve your mac performance. In addition you can also tyrn off the 'smooth fonts onscreen' in appearance control panel/fonts. It works, really.

why not render your vsti's to audio b4 mixdown?things generally sound more balanced with a single audio engine involved anyway..