What's the Optimal Hardware Buffer size?

[Chaos Rex]

I want to know where I should set my Hardware Buffer size. I have gotten underrun errors while playing/editing my tracks that suggest I lower the buffer size. I did lower it but seemed to get the error immediately afterwards. I have gotten the error when hitting the play button on my 002, no plug-ins being used. I've gotten it while adding a plug-in to a track I was playing, and I've gotten it while working with a plug-in (Trash). I am recording and working with electric guitar plugged straight into my Digi 002. I'd like to add a base line to. Eventually I'll be recording drums. But I want to know where my Hardware Buffer size should be set with what I'm working with. Can anyone explaine what 1024 samples is doing for me and if I really need it? The latency between me picking a note and hearing it through my headphones is minute but noticable. So far it hasn't bothered me. I'm more interested in what it's doing for me recording wise.

I have followed most of the Digi recommendations for system configuration.

My system:
Digi OO2
ProTools LE 6.4
P4 3.2 Ghz (Hyper Threading Diabled)
ASUS P4P800 Deluxe Mother Board (Intel 685PE chipset)
1 GB RAM
30 GB ULTRA 66 System Drive
200 GB ULTRA 100 Audio Drive
WinXP Pro

Plug Ins
BombFactory Bundle that Digi let us have for free.
Amplitube LE
Amplitube (installed after the problem started to occure)
T-Racks EQ
T-Racks (installed after the problem started to occure)
Whatever else was free with the Digi 002 that wasn't going to expire. (I uninstalled those.)
Trash (installed after problem occurred.)

Most of my backgroud processes are turned off. I have InteliType and InteliPoint processes running, I think that's about it. I have not diabled my ethernet at this point. It helps to register all those nifty free (and not so free $$$) plug-ins. I have set my preformance settings according to Digi recommendations (i.e. set for background processes and cache). Am I doing something wrong? Can I do something better?

Thanks
-Aaron

[tele_player]

It's pretty simple, really, unless I try to explain the WHY of it all. Small buffer sizes have low latency, but higher CPU load. Large buffer sizes have higher latency, and lower CPU load.

While tracking and overdubbing, using the lowest buffer size that works will minimize annoying latency in the monitor. You'll play tighter to the music.

When mixing, you can just max the buffer size, which frees the most CPU for all your plugin effects.

I find the latency when buffer is set to 1024 to be very annoying playing guitar, singing, or playing virtual instruments. At 64 or 128, latency isn't noticeable to me.

[TheLP]

I use 1024 all the time.........When I track I don't get any latency really.

[millicent frndly]

You can also turn on "Low Latency Monitoring" if you're computer can't handle a low buffer. (I use it alot.) It won't allow you to listen to plugins on that track while you're recording but you won't have the latency problems no matter what your buffer is set to.

A couple of things to check.. look at your IRQ's and make sure the Digi isn't sharing an IRQ w/ anything else. You can get things on different IRQ's by moving the cards around in your box. You can also turn off all that WinXP plush stuff.. graphic stuff. I can't remember where in the computer it is but if you search around in your settings you'll find it. (It's the junk like the fading in and out menus and other junk like that. I don't know how much of an effect your system drive being ATA 66 matters because I don't know how much the system drive comes into play when you're recording but I would think you have a slight bottleneck there too. Probably not much though.

Good luck w/ it, if you search around the DUC you can find lots of info on these buffer error problems.

chris

[Chaos Rex]

Thanks Tele and millicent frndly, I actually just did a search using the word "underrun" and found a ***** ton of stuff. I found one post that seems to give some pretty solid suggestions. I'll try them when I get home and with luck my problem will be solved. For anyone else having the problem, do the same search. The Neophyte posted one call "Re: Note about H/W Buffer errors, could save your life". It talked about making sure your drives are using DMA rather than see if "Use DMA if Available" is selected. I'll check that tonight. I'll also look into IRQs. Hopefully this works.

-Aaron

[tele_player]

1024 gives quite a lot of latency. If you don't notice it, fine, but it's there, and it's big. Most people find the latency using 1024 byte H/W buffer impossible to deal with for tracking or overdubbing. And this latency doesn't vary from computer to computer, so it's not that your system just works better.

Maybe you've been using LLM, or Mbox?

[keithl]

I agree teleplayer my website ..

I have found that 1024 is just not usable when recording