Maxing out an HD3 Rig

[Titans55]

Hello.

I currently have a Pro Tools HD3 rig, running Pro Tools version 8.4.cs2. My computer is an Intel 2.8 Dual Processor (8 core) MAC PRO with 4GB of ram. OS 10.5.8. I record and mix exclusively at 96K, 24bit. Most of my sessions have a bunch of virtual instruments and effect tracks. I also mix by bussing every track to an aux track and bussing that aux track to an audio track so I am able to record my mix to an audio track and export my song (instead of bouncing).
My playback engine is set as follows:
H/W Buffer Size= 2048,
Processors= 5
CPU Usage limit= 60%
5 DSP'S at 80 voices
Delay Comp= long

My Usage window is at:
PCI= 30%
RTAS= 30%

I am finding that when I am mixing I tend to get error messages saying that I am out of DSP power or that there is not enough free dsp for the mixer. Also, when I try to open a new tdm plugin it brings up a loading bar and then says not enough power and makes the plugin inactive until I switch it to RTAS. I also get error messages when bussing my tracks outputs to my mix buss. On larger track counts I get a message that says not enough free dsp for the mixer to make all my outputs active. I am confused. I mix completely in the box with the WavesTDM Mercury bundle.


Do I need to buy an expansion chassis and upgrade my HD3 rig by adding 1 or 2 my PCIe cards? Is there a way that I can free up room so I can add more tracks, use more busses, and use my TDM plugins. I just don't understand why my usage window says I am only using 30% of my PCI power and 30% of my RTAS power, but my system MAXED OUT. Please help.


I hope i have a setting wrong, because its hard for me to believe that my computer is that much more powerful than my 3PCIe cards.


Thanks

[kittonian]

The PCIe usage is simply telling you how much of the bus bandwidth you are using, not the usage of the chips on your cards. There is a window you can view by going to Window->System Usage and it will show you all 3 cards and how much is being used.

Remember that some of the nicer TDM plugs take up at least 1 full DSP per instance (Indigo, anything Eventide, anything SoundToys, etc.). If you're using AltiVerb TDM it takes up multiple DSPs per instance. If you're using HEAT that too increases the DSP usage, as does the Long Delay Compensation setting.

Adding an expansion chassis is certainly an option as I too often max out my HD3 PCIe rig. A lot of times I just convert a plug to RTAS on the tracks that aren't of the utmost importance, and/or record the virtual instruments into their own tracks when I know I'm not going to make anymore changes to them.

You need to ask yourself whether you actually need 80 voices or not as that is a rather high setting for normal usage, unless you are in the post world or doing sessions with a ridiculous amount of tracks. I have my system set to 3 DSPs/48 Voices. Your CPU usage should be at 85% not 60% though that won't help you with your TDM problem. Your H/W Buffer should be set at the lowest possible setting so you don't have any latency when tracking in MIDI. Remember that in TDM land the buffer setting means very little. Increasing it won't help you with anything but native (read: CPU) processing power. Since you have an 8-Core machine like I do, you should set the number of processors to 6 and leave 2 free for the OS.

Also, to directly answer the query as to whether your computer is that much more powerful over your cards, the answer is yes it is. However, the system itself doesn't allow for near zero latency when recording, nor any TDM plug-ins to run. No matter how fast your CPU might be you are limited to the DSP power of the cards themselves.

[Sean Russell]

I'm in the same boat - I bounce between several HD-3 Accels and I am usually at 24/88k, 5/80 voices with 7/8 processors, 90% CPU and 256 buffer. I get away with Short instead of Long ADC, but HEAT makes up for it in the DSP tax. 80 voices means that even if the arrangement isn't crazy busy, I still have voices left if I have to RTAS an AUX. I hate doing that, and all my templates are set with TDM's on Auxes and actual record tracks set out 1-2 (to be changed to busses as soon as parts are in).

I do mostly music in that setup (post work I run 48k). And my setups run hybrid - a lot of outboard. And the HD3 hates me with the punishment I seem to give it. Yet a lot of rooms won't go chassis and I end up trying to make it all fit in the HD3.

Earlier this evening, I opened a session on an older 4-core MP and got errors at 3/4 processors - the session couldn't hang unless I gave PT all four. I usually leave one open for the system.

[Barry Johns]

Start changing a lot of those plugs to RTAS vice TDM, it will open up your whole system! Give it a try, see where it works best and where it doesn't.

[Sean Russell]

All individual tracks are RTAS, only TDM's on Aux tracks (with the occasional TDM-only here and there on an Audio track.

It still gets gone too quickly

[holden]

I, too, work at 96/24. Even with an HD6/Accel I can easily run out of DSP on my medium size sessions. The best way to manage this is by using both RTAS and TDM plugins.

Keep in mind that the only reason to use TDM plugins in mixing is to be able to use delay compensation. Yes, there are a few plug-ins that are TDM-only, but they are the exception. With PT9's longer available delay compensation time you might even be able to do your mixing with all RTAS, but since you have the DSP cards you might as well use them.

A few tips:

• Wherever possible set any plug-ins on audio tracks to be RTAS.
• Wherever possible set any plug-ins on aux tracks to be TDM, until your system tells you that you have no more room for TDM— Only then use RTAS on aux's.
• Setup > Playback Engine > Delay Compensation > Long
• Options>Delay Compensation checked.
• Print all your instrument tracks to audio tracks.

Only if the above measures do not work should you spring for an expansion chassis and extra Accel cards.