Beating the Dead Latency Horse

After recording with my SAW/SAC for month's my church worship leader wants to run the SAC system for monitors and FOH. We had our first dry run last night and the singers kind of freaked out with the latency in the system. I was running 4 x 32 on my samples. We kept lowering the number of samples until we got to 1 x 32. The system performed flawlessly at that rate but the singers were still not happy. I am running the following converters.

MOTU 424 INTERFACE PCI-e CARD
BEHRINGER 8200 ADA CONVERTERS
MOTU 2408 MK3

I'm thinking the 1 x 32 sample rate should be well inside the 5 ms range. The new ADA8200 claim .6 ms in and .6 ms out. The 1 x 32 sample would be 0.7 ms. I'm going to give the MOTU stuff around 2 ms just for guessing. That is 3.9 ms. You shouldn't be able to hear that.

Up on the stage it is more like you can feel the latency instead of hearing it. Are the singers expecting too much? Or am I missing something?

Other than that the system sounded great. It was so clear. There was no noise or anything. It was kind of weird hearing something so clear verses the old analog system. I think that might have made the singers a little skiddish also, no junk or analog warmth to smooth over everyone's voice. I think he drummer and key board player loved it. They finally got the monitor mixs they wanted.

What do you think? Too picky or too much latency?

Quote:

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Originally Posted by Dale B

After recording with my SAW/SAC for month's my church worship leader wants to run the SAC system for monitors and FOH. We had our first dry run last night and the singers kind of freaked out with the latency in the system. I was running 4 x 32 on my samples. We kept lowering the number of samples until we got to 1 x 32. The system performed flawlessly at that rate but the singers were still not happy. I am running the following converters.

MOTU 424 INTERFACE PCI-e CARD
BEHRINGER 8200 ADA CONVERTERS
MOTU 2408 MK3

I'm thinking the 1 x 32 sample rate should be well inside the 5 ms range. The new ADA8200 claim .6 ms in and .6 ms out. The 1 x 32 sample would be 0.7 ms. I'm going to give the MOTU stuff around 2 ms just for guessing. That is 3.9 ms. You shouldn't be able to hear that.

Up on the stage it is more like you can feel the latency instead of hearing it. Are the singers expecting too much? Or am I missing something?

Other than that the system sounded great. It was so clear. There was no noise or anything. It was kind of weird hearing something so clear verses the old analog system. I think that might have made the singers a little skiddish also, no junk or analog warmth to smooth over everyone's voice. I think he drummer and key board player loved it. They finally got the monitor mixs they wanted.

What do you think? Too picky or too much latency?

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There has to be something else going on. 1x32 for a singer is undetectable with a floor monitor. (it will potentially cause phase anomalies in a IEM due to the difference in latency from direct bone conduction and the delayed sound coming from the IEM.)

If your using IEMs adding a small amount of reverb to the vocal will smooth that out.

There is possibly something else patched into the system that is adding some serious additional latency... check for any delay in the signal chain.

I run dozens of setups at 2 x 64 and no-one ever complains about latency... Elton John is running 2 x 64.

Bob L

Using Asio driver?

Are you using floor wedges or IEMs
I have only had 2 people using IEMs that noticed latency at 2 64 in the last 5 years
No one ever noticed anything in floor wedge
I had a problem in an IEM last week when I forgot I had my FOH headphones also patch to his output and I had added delay delay to my cans :o

Butch

I am using the ASIA driver from MOTU. I went in yesterday and ran some tests using RTL program. The window driver is horrible but the ASIO driver with the system below gave me well under 5ms at 44.1 and 48.

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We are using floor wedges for monitors. The drummer uses phones. I don't think I have any delays, reverbs, or echoes plugged in the system. I'll check.

Quote:

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Originally Posted by Dale B

I am using the ASIA driver from MOTU. I went in yesterday and ran some tests using RTL program. The window driver is horrible but the ASIO driver with the system below gave me well under 5ms at 44.1 and 48.

Attachment 2454Attachment 2453Attachment 2452

We are using floor wedges for monitors. The drummer uses phones. I don't think I have any delays, reverbs, or echoes plugged in the system. I'll check.

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With floor wedges and the 3ms latency being shown, your singers are not hearing any latency. It is literally the difference of the floor monitor being moved 3 feet further away.

More likely the audio is a whole lot cleaner than what was there before with the analog board. (NOT analog warmth but rather Analog mush). Your singers are just not used to actually hearing themselves.

Only other explanation is there is a delay patched in somewhere.

If SAW is linked to SAC, make sure you turn OFF the SAW monitoring in the Options menu/Audio Switching Protocol, or you will here a large delay from SAW itself after whatever latency is in SAC.

When using the SACLink, all monitoring should be done in SAC only... SAW should not attempt to use any monitoring protocol, like the Tape Style in this option setting.

Bob L

We ran the system Sunday and it ran well. I had a windows update virus protection show up and some slipped buffers after that. I restarted the engine and no slips for the rest of the session. I need to go in ans disable the update to prevent the slipping. The musicians said there wasn't any noticeable delay either. Not sure what happened.

The system sounded great. Noise level in the place was, well, "quiet as a church mouse." This is the first time I've run the system live with 16 channels going. Two outs to FOH and three monitor mixes. Ran around 20%.

I am running SAW linked into SAC so Bob I need to go and check monitoring settings you suggested. Right now I have on clue how it is set. I'm going to try and add a few more buffers to give the system a little wiggle room. Right now still at 1x32.

I will keep everyone informed.

Thanks,

Dale

Good... try 1 x 64 or 2 x 64... that should help with the slipped buffers.

Bob L