Latency question, or "If it ain't broke, should I still fix it?"

[CurtZHP]

Recently built a new system. Intel i5, 4GB RAM, Still using XP. Interface is a MOTU 2408 MkIII. (Planning to upgrade Windows in the near future.)

Anyway, I started messing around with the Out Preload Buffers and Out Buffer Size settings, having almost no clue what I'm doing.

It seems like anything less than four output buffers gets me in trouble, as does any buffer size less than 1024.

Is this normal? Also, the MOTU has its own buffer size settings. How do they factor into this?

[Dave Labrecque]

Recently built a new system. Intel i5, 4GB RAM, Still using XP. Interface is a MOTU 2408 MkIII. (Planning to upgrade Windows in the near future.)

Anyway, I started messing around with the Out Preload Buffers and Out Buffer Size settings, having almost no clue what I'm doing.

It seems like anything less than four output buffers gets me in trouble, as does any buffer size less than 1024.

Is this normal? Also, the MOTU has its own buffer size settings. How do they factor into this?

Seems like you oughta be able to do way better than that with an i5. Though, I know nothing about the MOTU stuff. I assume you're not bogging the MT down with plugins for this testing?

[CurtZHP]

I wasn't using any plugins, and I only had three tracks recorded.

I'm not in front of the workstation right now, but I don't remember which audio driver setup I'm using (WMD vs. ASIO).

[Jeff Scott]

I run comfortably on 2x64 and Win XP Pro 3 on an older ASUS motherboard. (look below for specs). I use a RAYDAT card. Only when I'm using a TON of heavy CPU plugins ...like Superior Drummer, a couple of Synth VSTi's and a dozen Guitar Amp plugs do I need to bump it up to 4x 1024.

[CurtZHP]

Must have something to do with my interface. This thing shouldn't even be breaking a sweat.

[CurtZHP]

Just for grins I tried the same session on my laptop, which also has an i5 processor. Granted I'm using the built in POS sound card. I get the same result.

Unless I have at least 3 buffers set for at least 1024, the audio is very slow and very garbled.

[Dave Labrecque]

Using my MBox2 Mini, I can go down to 1 buffer at 128 on a four-track session playback, FWIW. Can't do anything at 64 for some reason. Must be this device/driver. I'm on a Sandy Bridge i7 (four cores, each threaded for 8 'logical cores').

Could multi-threading me messing with you? Doesn't create a problem for me, but I thought I'd ask.

Can you try another audio device just to compare? My integrated Realtek mobo audio device (DirectX driver) can play the same session at 6x512 or 8x256. You GOTTA be able to beat that, I'd think.

Using an ASIO driver, you set up the buffer size in the driver, then it's locked at (and should display) that value in any programs that use it. Are you doing an ASIO driver or DirectX or... ?

[Dave Labrecque]

Just for grins I tried the same session on my laptop, which also has an i5 processor. Granted I'm using the built in POS sound card. I get the same result.

Unless I have at least 3 buffers set for at least 1024, the audio is very slow and very garbled.

If you want to send me the session, I can try it here and tell you what happens.

[Angie]

Are you doing an ASIO driver or DirectX or... ?

I think that should have been the first question.

[DominicPerry]

Sounds like you are using the WDM drivers. You should be using the ASIO drivers if you want low latency.
Mr RBIngraham is your man for MOTU advice, I'm sure he will chip in.

You should, as a general rule, use a multiple of 2 for buffers (2,4,8, etc) and the size (32,64,128,256,etc) is whatever you can get it down to without glitching.
In and Out will be the same size (e.g. both 128 samples), and you would normally set them to the same number too (both 4, for example) although that isn't strictly necessary.

Bear in mind that the latency for 4x64 is the same as 2x128. But one may work better than the other.

You should fix this (ie work out what you are doing and what can be achieved) before you upgrade your OS. Firstly, because you may decide you don't need to upgrade, and secondly because when you can't get Win7 or Win8 to work as well as XP, you want to be sure you're comfortable with the buffer setttings and it isn't that which is causing the problem. I think that WDM drivers are very different in Win7&8 from XP.

Dominic

[RBIngraham]

Ummm.. oppss... did I miss my cue or something? ;)

I don't have any of the i series CPUs in my stock pile. So unfortunatly I can not really comment on that. And I rarely have SAW talking directly to the ASIO sound card driver. It's ussually through the SAC-SAW link.

Having said that, I run at 2x64 all the time, with Core2Duo systems. And even on my largest SAC shows (where I have used almost all the inputs up in SAC a couple of time) these machines barely get above 40 to 45 percent on SAC's CPU meter.

I'm not really certain where you're setting the buffer size at. On my systems I have to set the buffer size in the MOTU set up app first. (sorry I forget what they call it now, something like MOTU Console or something) That is how I set the ASIO buffer size. Then I set the number of buffers in SAC's Audio Set Up.

I could be wrong, but I think the procedure is the same in SAW, I just don't have it handy in front of me at the moment.

Hope that helps a bit.

[CurtZHP]

Thanks everybody. You've all given me a few things to try tonight. I'll report back once I've done that.

[Dave Labrecque]

I think that should have been the first question.

It's Curt. I was giving him the benefit of the doubt. ;)

[CurtZHP]

Well, that's what it was -- the WDM driver. Once I switched to ASIO, I was able to get it down to 2 buffers at 64, and a 17 channel mix with plugins, edits, and automation aplenty ran without a burp! Multitrack Load maxed out at about 6%.

That's more like it!

Thanks again, everyone! I knew it would be something simple.

[Dave Labrecque]

Well, that's what it was -- the WDM driver. Once I switched to ASIO, I was able to get it down to 2 buffers at 64, and a 17 channel mix with plugins, edits, and automation aplenty ran without a burp! Multitrack Load maxed out at about 6%.

That's more like it!

Thanks again, everyone! I knew it would be something simple.

In the future, if you have any issues, just send a PM to Angie. ;)

[CurtZHP]

What if I don't have any issues. Can I still send a PM to Angie?

[Dave Labrecque]

What if I don't have any issues. Can I still send a PM to Angie?

Can't speak for her, but good by me. ;)

[Angie]

What if I don't have any issues. Can I still send a PM to Angie?

:)

As soon as I noticed you were using a MOTU, I knew you were using the wrong driver. MOTU's WDM driver is awful. That said, I still use it in SAWStudio because I like to be able to simply close SAC after tracking and start mixing without having to restart SAW. Latency in SAWStudio isn't as much a concern for me as it is in SAC. SAC loads the ASIO driver on default.

[CurtZHP]

I'm not even sure how I ended up using the WDM driver. Probably just installed the software, assigned the sound cards, pulled up a session, and checked for audio. "Yeah, great, it's working." Then I got preoccupied with other projects where latency wasn't an issue, or I was using something else.

Couldn't test for ASIO on my laptop because I didn't have an ASIO interface for it.

Then I went to work on a music project (first time in a while), and after laying down a scratch guitar track to the drums and playing it back, it was like, "My sense of rhythm is way better than that! What the heck??"

I'm just glad something wasn't broken.