Should I get a PCIe based system to reduce my latency with VE Pro?

[kabin boy]

Hello friends, I'm new to VE pro and am having some trouble getting off the ground.

I've successfully networked my machines (specs at bottom), and my mac pro running the latest version of pro tools 10 is able to connect to my PC slave.



The problem I'm encountering is that the hardware buffer setting required to get a clean signal from one instance of VE pro is much too high to be usable for overdubbing. In addition, I am experiencing latency upon playback from the slave in proportion to the same hardware buffer setting. (around 512 to 1024 required to avoid distortion and drop outs)



I am experiencing these problem while running pro tools without any additional plugins except a single VE pro instrument. The slave is loaded with a single instance of Kontakt 16 out.



I believe the weak link may be that I"m using an old piece of hardware: The firewire Digi 002. My question is, what are the steps I can take to reduce this required hardware buffer setting, and make the latency much lower?

My inclination is to spend $$ on a PCIe based audio card, but I'd like to hear your advice first. I'd also be interested in hearing what buffer settings others have been able to find usable on their Pro tools systems, and what kind of audio cards they are using.


Thanks for your time!





Master: Nehalem Mac Pro 2.66 with 24GB RAM. Latest version of pro tools 10 (downloaded this week) Newest version of VE Ensemble Pro (same version both machines) Digi 002 firewire interface



Slave: intel i7-4770K 3.5GHz 32GB RAM VE pro with Kontakt.

[civilization 3]

Well, PCIe in a Northbridge slot, probably the first available one on your machine is 'Slot 2', is the fastest bus to the CPU. I don't know if other technology supplaces this conceptually or not.

[Cyril Blanc]

I dont know PT, I use Logic, but as I see that there are not many person that are trying to help you I will try to help you to narrow down your problem !

You have to know that you need a lot of speed in the disk I/O with the sampler players !

If you put Kontakt in VE Pro you add another layer so you need more power

Do you use other libs than K5 ?

Did you try to use the internal audio port ? can PT use it ? does it improve ?

Where are your samples ? on disks ? what disks ? on FW bus ? on the same bus that the Digi 02 ?

How are linked your MAC and PC ?

[kevinhendrickson]

Hello, thanks for trying to help!

You had a great Idea -- I tried disconnecting my firewire interface (Digi 002) and using the Mac's internal sound card. No change.  There are no other firewire devices either.

The Mac and PC are linked by cat 6 cables and a gigabit switch. There is nothing else on the network.

The slave has lots of power -- all samples -- Kontakt library, PLAY -- are hosted there. There are no firewire drives. The samples are on internal mechanical drives on the slave.

I can fairly safely run 512 samples Pro Tools buffer, but it seems much higher than it should have to be. And it still gives the occasional dropout.

As a side note, what is normal traffic for an ethernet network when the transport is stopped? Mine shows about 4 to 5  million packets sent, and about half that received. It says the link speed is 1 Gbit/s. (I checked both PC and Mac)

I'm using DHCP assigned IPs. I did once change them to static addresses, but it made no difference. 

Thanks

[Cyril Blanc]

Most of the time the bottle neck is the DISK I/O

But if the bottle neck is the Ethernet you could add a second ethernet card on the slave and use the 2 ethernet port of your Macpro.

I have not test that, you should find a confirmation with VSL, They have done huge test trying to saturate the Ethernet

Normally you do not need an Ethernet Switch, just a cable and you should use FIX ethernet adresses see :

http://cyrilblanc.fr/site_principal/slave_mac.html

To gain another solution is to put a SATA III card and SSD or raid of SSD, you could then try to reduce the pre-load buffer size.

Using SSD is nigth and day !

If you look to my configuration, I have a template of 100 instruments, I can play pieces like "From the New World" of Anton Dvorack with MIR PRO in 5.1 and 7.1 with all tremollos are done with notes, and there are very fast ones in that piece

You also have to look as using PLAY the little possible and not to put it in VE, When you add players in VE you add overhead onto them !

When I used a Master + slave configuration , I have put MIR PRO and all my VSL on the slave*, Logic + Kontakt + Play on the master.

The audio tracks from K5 and QLSC where send to the slave to go in MIR

The slave had a Raid 0 of 6 x Raptors disks to put the samples.

Hope that's help's 

Best

Cyril

The Master was an 8 core Macpro 3.1  and the slave is my 12 core Macpro 5.1

[kevinhendrickson]

Great, thank you. I am noticing an increase in stability after upgrading to SSD drives for all of the mac pro drives.

I also have determined that the firewire interface was causing a problem. Perhaps it was the old ASIO drivers.

I will try the fixed IP addresses and direct cable next.

I am making progress... thanks again.

[Robert Mackenzie]

Hi Kevin, I'm wondering if you managed to get the latency down to a workable amount. I am considering a similar setup.

[kevinhendrickson]

Hi Robert, yes I did manage to reduce my latency quite a bit and have found the system to be very usable. I can throttle the HW buffer up to 64 samples as needed, but I find it most stable at 128 or higher.

I have been able to run two instances of VE Pro - one on my host Mac pro and one on my slave PC. In addition to dozens of virtual instruments, I have been using the Audio Unit plugins to route audio from Pro Tools 11 through the VE pro consoles allowing me to use my old collection of 32 bit plugins to process audio andthen  bus it back to my 64 bit DAW. I haven't experimented much with running additional instances, but I'm pretty sure it can be done.

There were several small changes I made to my system to achieve this, but the most important was removing all Avid / Digi 002  drivers from my system. Even though they were the latest drivers, the caused havoc with VSL pro even after I had stopped using the Avid hardware entirely. I had overlooked the step of actually uninstalling the drivers. Once I went back and did this, the performance increased substantially.

The other changes I made each caused an incremental performance boost. I'll list them here in order of importance:

• Removed (uninstalled) all traces of Avid Digi 002 driver software
• upgraded to pro tools 11 native (seems to manage plugins better)
• weeded out certain aax plugins that were causing dropouts. I eventually learned that one or two plugins, when inserted on any track in pro tools, seemed to cause audio dropouts on other channels or busses. 
• Replaced system drive with SSD
• Replaced Pro Pools recording drive with SSD
• Installed a RAYDAT pciE card. I'm can't verify that this caused a reduction in latency just by the fact that it is PCIe based. It's possible that a different firewire interface with much better drivers than the Avid may have helped as well. However, the RAYDAT has worked very well for me. I list it at the bottom here to make clear that this isn't the only hardware option that will work.

Good luck!

Kevin