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Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 12:19 pm
by Andy_F
For example if i max out the cards i get the message asking me if i would like to reload all devices to free up some space.. Can this be done manually?
Ive recently started using the Scope environment for mixing/sub mixing from Cubase using the STM mixers, and ive discovered the stereo pair phase problems
I have the phase fix device but this does not load as an insert (obviously it would/could create its own phase problem

)
If i understand the problem correctly its caused by L+R being spread across DSP chips or even worse actual cards.
So im thinking if i notice this with a certain insert i can force a DSP optimization and hopefully get L+R in sync?
Also.. are some devices programed so L+R are aways phase synced? Optimaster for example?
Im really trying to learn all i can about this issue as all the projects i mix will be played over club systems, so mono compatibility is essential!
Re: Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 1:13 pm
by garyb
have you tried the check box for phase compensation on the stm2448 and stm4896 mixers? it's for that very purpose of making sure that stereo pairs are in phase....
Re: Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 1:39 pm
by Andy_F
Yeah i have had that box ticked and also set for all channels on board 1.
But i think the phasecomp option on the mixers only works without any insert fx.
On stereo tracks ive found some insert effects are creating a small delay between L+R. Not every insert on every channel but by the end of a full mix using all mixer channels there will be a couple which sound thin or vanish in mono.
Re: Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 1:45 pm
by garyb
lots of stereo tracks are a serious traditional mixing no-no for reasons just like that. the more stereo sources the more room for bad trouble, especially using hardware, although i know that romplers in a sequencer should be compensated and safe, but they often aren't. many musicians are in very bad habits because of this these days.
anyway, i'm not trying to tell you what to do, i'm just talking about it. perhaps some of those effects should be used outside the mixer?
Re: Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 3:25 pm
by at0m
Andy_F,
To answer your original question, you can re-order DSP's by switching sample-rate master/slave (and back). Do not forget to mute your mixer/monitors/..., it may pop!
About your underlying problem, the phase, I'm not sure which to trust better - Steinberg or S|C's ASIO drivers, since I didn't test further, but routing a mono synth to a stereo ASIO input gave me a couple samples offset on Cubase's track. I was stunned.
There is a fix, though, and I will paste from a post I just made here on z for someone else: Check ReD_MuZe's
Phase Fix. The page is a bit garbled, but you can find the file's url and it's still there. It's a convenient tool to solve the problem: Set STM to Mono, Solo tracks one by one. Insert PhaseFix, and set it to invert one channel and adjust sample delay untill you're satisfied (with stereo effects, you can't create silence, or you'd better be using a mono track eh) and set PhaseFix back to 'stereo'. Solo the next track and go on.
This may look cubersome, but it sure is a fix for phase troubles!
On a side note, when using different microphones on different tracks of the STM for example, you can delay individual channels of the STM, but not separately for L/R. That's where PhaseFix comes in :)
at0m.
Re: Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 4:12 pm
by Andy_F
Yeah thats exactly what i had in mind.. i'll try the master/slave button.
Im hoping it might be a quick and easy way to get the L+R to reload on the same DSP but on the other hand could make others go out of sync. I'll try it out and see
I have been using that phase fixer already so i guess im on the right track and shouldnt worry
The sample delay on the STM mixers is genius, both for fixing problems and creative uses like drum layering.
Gary, I do only use stereo channels when needed but with sub mixing out from Cubase thats most of the time. Small delays between separate channels doesnt bother me, just the L+R of stereo pairs.. An entire drum mix losing everything above 1khz in mono for example would have been a disaster if i'd not picked up on it

Re: Is it possible to force a DSP re-order? (PCI Cards)
Posted: Thu May 06, 2010 6:48 pm
by garyb
AndyF-that's for sure...