Outboard Reverb Latency

[ripeart]

Not being satisfied with any of the Waves reverb offerings, and not looking forward to spending countless hours demo'ing verb plugs/reading reviews I was very happy to fall into the opportunity to purchase a mint Lexicon PCM 91 for $400. (It took a lot of whittling the seller to get to that price.)

I was wondering how you folks use outboard effects when mixing. Currently I have the analog ins and outs connected to my 828.2 and via DP am sending a signal to it, then back and recording the verb on it's own track. As expected I do notice a bit of latency. I compared the original and verb signal waveform and the beat detection indicator and judged that the verb is about 4 ms late. I'm not sure if that's an accurate way to measure though, and I know that 4 ms is an almost insignificant amount of time. Thinking that, should I be worried about latency with this unit? I like to use a Linear Phase EQ often and that CPU muncher increases latency across the board more than most other plugs. Should I be on the lookout for latency issues using an outboard device? Is there a more efficient method of interconnection, such as the AES connector?

Thank you for your thoughts =) and I am LOVING this verb unit.

[Phil O]

For a long time, I've used a simple impulse to measure outboard latency. Record an impulse, send it through the system and re-record it, then just compare to the original. If you zoom way in in the SE you can see the delay and easily measure it. I just measure it in samples set my nudge to the appropriate amount and nudge the soundbite ahead. Other folks here prefer the more elegant Latency Fixer:
http://www.expertsleepers.com/latencyfixer.html" onclick="window.open(this.href);return false;

Phil

[HCMarkus]

If your Mac is properly set up, your should see no latency if you are recording the reverb to a separate track, then playing back that track with other recorded tracks as you mix.

Unless you are using the Lexicon to handle chorusing or EQ, 4ms additional predelay is easy to manage at the patch level (if it bothers you at all) as long as you return a purely "wet" signal to your mix.

[ripeart]

Latency Fixer:
Phil

Hey neat, exactly what I was looking for. I think I'll give it a go, thanks!

If your Mac is properly set up, your should see no latency if you are recording the reverb to a separate track, then playing back that track with other recorded tracks as you mix.

Unless you are using the Lexicon to handle chorusing or EQ, 4ms additional predelay is easy to manage at the patch level (if it bothers you at all) as long as you return a purely "wet" signal to your mix.

Yes, I'm returning a 100% wet signal to the board. I'll tell ya, I don't even notice that there is any latency at all, it's only when I returned a dry signal back to a seperate track and examined the waveforms that I noticed they didn't line up. I 'nudged' the track 4 times (my nudge is set to ms) to get it lined up so that is where I got that figure.

Also to monitor this thing, I've created an buss for the Lexicon, then two aux tracks, one for the send with the buss as it's input, one for the return with the lex out as it's input. When I want to send it a signal, I use the Lex buss fx send. When I want to print it, I'll simply create a stereo track for just the verb. Is there a more efficient way of routing this signal rather than the two aux tracks I have made?

Probably a picture is better: Click on it for full size.



Thanks so much for your comments.

[HCMarkus]

I just noticed you have an 828mkII. If you are mixing down real-time (which you have to do if you don't want to print your outboard reverb), why not return the Lexicon via CueMix using the "Mix" input to feed your mixdown destination track. With the 828mkII, you can set the Mix to include both the computer audio and the CueMix audio. This is how I get external MIDI modules' output into my mixes "live", along with my own (albeit less fully-featured) outboard Lexicon reverb.

[ripeart]

AH, I had a sneaky suspicion that CueMix would be helpful here. I'll definitely look into that. Very cool, thank you!

[EMRR]

In almost all cases one would use some amount of predelay with a reverb, and usually any latency would be a mere fraction of that quantity.