How about latency ?

[Chris Lambrechts]

Just wondering ... not a 'live' engineer by far ... in fact I tried it at some point long time ago. Big Band, live, 15 minutes to soundcheck ... in short peed my pants and decided never ever to do it again. So apologies if this seems a dumb question.

Anyhow. Now that digi technology finds it's way to the live environment, how about latency ? I'm talking not only about convertor latency but everything that might come down the line.

I was thinking this over the other day. Monitoring on stage for example : Drummer plays ... AD / processing / DA / buffer sizes .... in the end it all adds up and at some point I can imagine a drummer or a keyboard guy moaning about hearing himself later then he plays.

Is there seperate routing for monitoring stuff etc etc ... curious how it works.

[mattpete]

With respect to VENUE, the analog in -> analog out latency on the stage box (through the complete system) is ~2.8 ms. This is slightly longer than the same latency measurement on an HD 192 I/O @ 48kHz, so if you've ever fed a musician a headphone mix of themselves via Pro Tools, they are experiencing the same delay.

I suspect that the most sensitive performers wearing IEMs may be able to hear this delay, but does it bother them? Other digital consoles have the same issue and it does not seem to be a big problem. Any type of digital insert processing on an analog console will cause a similar latency.

If monitoring is via wedges, then there will be propagation delays of about 1ms per foot between the speaker and the performer's ear, so the latency of VENUE is not an issue.

As far as internal processing, the above latency spec is for the complete 96 channel mixing engine measured from a stage input, along the snake, into a channel, through the built-in EQ/Dyn section, via a Group, then to Main and back down the snake to stage output. Adding a plug-in or two will increase your latency by a few samples per plug-in, hardly noticeable. Very few plug-ins applicable for live use will have more latency than this. There is built-in delay compensation for the internal submixers as well (defeatable).

Does this answer some of your questions, Chris?

-Matt

[Chris Lambrechts]

Does this answer some of your questions, Chris?

-Matt



absolutely ... thanks. What I figured too. Indeed, like you mention, convertor latency is inherent to digital systems. Processing latencies can run up quite a bit and become a hassle in studio environments.

Another question. Sorry to be a curious nose but just kinda wondering how much this 'digital' environment approach which is I guess rather new to the 'live' circuit compares / translates to my world ... the studio environment. How about outboard ? Would you still use those racks of outboard comp's / eq's / reverbs etc etc or could one consider the future of live to be ITB (in the box ?)?


Thanks

[mattpete]

Sure, if you've got outboard gear you can't live without (and can't figure out how to get a plug-in to do the same thing) you can always use the analog or digital insert points on the FOH Rack. The analog inserts will add another couple ms of latency to your signal path, which is about 100x more than the typical plug-in. So it definitely pays to keep your processing in the plug-in domain. Plus, plug-ins weigh less.

-Matt