The No.1 Website for Pro Audio
 All  This Thread  Reviews  Gear Database  Gear for sale     Latest  Trending
two latency/phase questions....
Old 24th June 2009
Gear Nut
slipperydip's Avatar

two latency/phase questions....

I'm a singer/songwriter not a mix engineer so apologies if these things are obvious... here are a couple of things that I'm curious about as I want to get my mixing skills better, interested in your thoughts and whether there's any plugs that could help:

1. Let's say I do some parallel compression of kick, bass etc. Let's use the bass as an example... if in Logic (or any DAW, or console) I send the dry signal out to an aux and then apply compression and maybe an eq, and then mix that back in with the dry signal... the two signals (dry, compressed/eq'd) are likely now out of phase due to the latency of the plugins on the aux. So, what's the best way to handle this? Do you setup a delay on the dry signal? If so, how do you know what the latency is that is being introduced? ... or do you just setup a delay, move it around and use your ears? Are there any plugins to help with this?

2. I've been experimenting with gated sine waves, side-chained to the kick and mixing this in. I like using it subtly and I think it's going to be useful, but even dialing up the "look ahead" in logic's gate that supports side-chaining, I can't get them to sync up well. What are your thoughts? Do I have to bounce this sine out to an audio track and then go back and align it by eye? Again... are there any plugins that would make this easier?
Old 24th June 2009
Lives for gear
norman_nomad's Avatar
1. If logic doesn't report latency on busses in samples or doesn't have auto delay compensation then you'll need to do a latency test and adjust manually. One way to do this is to send a track with a sharp transient (like a snare hit) through your aux and record/render the result. Import that back into the session and then manually measure the sample offset from the original file. Voxengo makes a free plugin that will offset tracks by a certain sample designation and you'll have to use this on all the non-affected tracks so that they align perfectly with the affected tracks. Or you can nudge the non-effected tracks forward by the specified sample amount to get properly aligned playback. Remember that non effected tracks should be moved by the total amount of sample latency occurring in the system (Sound like a pain? It is...)

2. Duplicate your kick track and nudge it backwards by the sample delay induced by the gate/sine wave generator then use this file to trigger.
Old 24th June 2009
Deleted User
First of all, analog hardware does not induce a delay... Certain phase characteristics maybe, but not time.

Secondly, I usually duplicate the tracks, and insert the same plugins on each track, with the dry track's plugins bypassed. They will still cause the same amount of delay on the "dry" track but not effect it in any other way.

You can also do this with aux tracks... Assign multiple tracks sends to, say bus 11 and 12. Make 2 aux tracks that both have 11 and 12 as the input, sent to the same output. Insert the same plugins on both aux tracks, but with one tracks plugs on bypass.

Any other way, in my opinion, is too complicated, and still might not be accurate enough. I even find this better than ADC.

Old 24th June 2009
Gear Nut
slipperydip's Avatar

Originally Posted by Thumper View Post

... I usually duplicate the tracks, and insert the same plugins on each track, with the dry track's plugins bypassed. They will still cause the same amount of delay on the "dry" track but not effect it in any other way.
Provided the bypassed plugins have the same latency effect as an active one (I gather this is the case?) then that would work. But seems a bit crazy when you scale it out... eg. let's now say I have four tracks that I want to mix together to get my bass sound:

1. Raw
2. Light compression
3. Heavy compression
4. Overdriven

With this 'bypass method' - as a simple example* - if I am using say my URS channel strip on #2, Vintage Warmer on #3 and GTR3 on #4. Would I have:

1. URS, Vintage Warmer, GTR3 - all in bypass
2. URS (on), Vintage Warmer (off), GTR3 (off)
3. URS (off), Vintage Warmer (on), GTR3 (off)
4. URS (off), Vintage Warmer (off), GTR3 (on)

A couple of questions for you GSz:

- In logic using AU plugins, do I then have any overhead (CPU etc) from the 12 (ie. 4 x 3... 9 of which are in bypass) instances of plugins running when I only actually want (before considering phase/latency issues) 3 instances?

- This seems a bit crazy... why haven't DAW developers figured out a solution?! <potentially-over-simplifying> when you group auxes, this latency correction/normalisation is handled automagically. Have they?

- Is this 'best practice' (a dangerous term around here I know, but this seems straightforward DAW time compensation stuff not subjective audio chocolate rah rah), what are other people doing?

... I'll check out that Voxengo plugin too...

* these are not necessarily the plugins I am suggesting I would use on bass, just using as an example.
Old 24th June 2009
Lives for gear
norman_nomad's Avatar
Slippery - You've pretty much got it right. When you're doing dense parallel processing or complex bussing it gets more complicated and requires many plugs stacked in bypass which DO require resources from your machine.

Lack of auto delay compensation was the primary reason I jumped ship from PTLE nearly 3 years ago and switched to Nuendo/Cubase. Not including ADC in a modern DAW is, as you put it, "a bit crazy" IMHO. It's a work flow killer to say the least...

I'm sure there are some clever work arounds if you want to stick with Logic... maybe some seasoned Logic users can chime in with their thoughts...

Best of luck.
Old 24th June 2009
Gear Nut
slipperydip's Avatar

thanks... so, cubase/nuendo has this problem solved somehow?

It seems like Logic assumes you want to do everything on one channel - especially given the ridiculous inability to move auxes around without adding them to the arrange window (wtf?) - so I might be jumping ship soon as parallel seems to be getting me closer to where I need to be and logic is getting in the way.

I'll have to look into whether logic has ADC...
Old 25th June 2009
Lives for gear
norman_nomad's Avatar
Cubase/Nuendo does all the latency compensation for you... when you add a plug or series of plugs, it automatically figures out the sample delay and adjust so that ALL tracks during playback are in sync with one another.
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.

Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump