Logics internal routing latency, or am I missing something?

F

figgebass

Logician
Hi.

Right now I am trying to find a system that has as low latency as protools and after testing Ssl's Madi extreme, RME's hdspe and some new rme-usb interface that's supposed to be LIGHTNING fast I am still getting annoyed by the latency when I record via logic.

Ssl claim that the roundtrip latency is below 2 ms and sure , it is....if you are recording something that you are playing back from another track on the computer and the reason for this is that the material being played back is buffered and therefor logic has already calculated everything it needs to calculate before it starts recording on the next track.
If you do as follows you get more "true" results:

Track one playback already recorded material through physical out 1 which you connect (via cables and not internally in the computer, d/a-a/d) to physical input 2

Track 2 uses input 2 and records what comes in and routes it to output 2 which you connect to physical input 3

Track 3 records whats playing back from the recording track 2.

Tracks 2 and 3 should be armed and recording both at the same time.

Now, between tracks 1 and 2 (the original and the first copy) I get slightly less than 2 ms latency.
between trck 2 and 3 I get 5.2 ms latency.....If I keep doing this and record on track 4 and track 5 I keep getting 5.2 ms latencty between a track and the previous.

SO ...even though the a/d-d/a latency is below 2 ms logics routing of unbuffered material adds over 3 ms....

I know I am extremely (overly?) sensitive to latency so please don't start arguing with me regarding what I can and can not feel, ok? ;-)
I also have a protools rig and what happens when I do the same test there (with logic) is that between the first and second track there is a latency of 2 ms and between the second and third there is also 2ms latency and so on.
This is because the signal never ever enters logics routing....or the mac's processor, if you will...

PLEASE someone tell me that I am wrong about this and I just need to check some box in logic...but I fear I will have to go Protools HD to achieve a really professional recording environment for me and my clients....=/
 
Peter Ostry said:
What is the actual problem?
Internal latency, recording latency, I/O with external hardware, or monitoring?
Click to expand...

I'm sorry if it's confusing but the problem is the internal latency within logic when routing/processing material it has not buffered which gives monitoring latency while recording audio. 🙁
I hope there's a work around but I guess that if you go with native it's just something that I'm gonna have to live with since the audio must enter the computer to be routed back out for me to hear it. In protools it never enters the computers processing but stays on the protools dsp's.
Is there a native card with dsp's?

I have tried Focusrite Saffire but I need something with really good inputs and a/d-d/a.
 
figgebass said:
Is there a native card with dsp's?

I have tried Focusrite Saffire but I need something with really good inputs and a/d-d/a.
Click to expand...

I suggest that you taker a close look at Metric Halo. I use both their 2882 and ULN 8, yesterday I was mixing a band live, routing all the audio through just the 2882, controlled from my Core Duo Mac Book Pro which also recorded the gig. There were no complaints about latency 🙂

kind regards

Mark
 
Thx. can't find anywhere stated what kinds of plugins there is onboard....is there an amp-sim for example?

Markdvc said:
figgebass said:
Is there a native card with dsp's?

I have tried Focusrite Saffire but I need something with really good inputs and a/d-d/a.
Click to expand...

I suggest that you taker a close look at Metric Halo. I use both their 2882 and ULN 8, yesterday I was mixing a band live, routing all the audio through just the 2882, controlled from my Core Duo Mac Book Pro which also recorded the gig. There were no complaints about latency 🙂

kind regards

Mark
Click to expand...
 
figgebass said:
internal latency within logic when routing/processing material it has not buffered which gives monitoring latency while recording audio. 🙁
... In protools it never enters the computers processing but stays on the protools dsp's. Is there a native card with dsp's?
Click to expand...
There are interfaces with DSP but they still employ an A/D conversion plus little time for routing/processing plus a D/A conversion. Although this system is called direct monitoring by the interface manufacturers, it is not direct at all. It can be called "low latency monitoring". The latency is really low and acceptable for most people. All modern interfaces from the mid-range upwards support this type of monitoring. I would say that bus cards have the potential to be the fastest, then Firewire, then USB. This may not be true forever.

But since you say that you are extraordinary sensitive to latency you may consider to go one step further and eliminate all latency of your recording path. Therefore you split the recording signal either after the mics and instruments or after external preamps and other hardware you may use, but before the audio interface. Monitoring is then be done through analog hardware only and practically latency-free.

Below is a drawing of the system I use myself. I work with mics, real instruments and software instruments and had always problems with latency until I changed the whole system:

20091115-8f77t3gxrm4acbtgrjr2nph64t.jpg

​

Be warned: If the interaction between the interface and the DAW is correctly set, nobody can blame the system if people don't play in time. It's all their fault because there is no latency in the path 🙂
 
Wow 2ms latency, that is impressive perception!

I have the Jerk's sense of rhythm ;-)

To avoid latency all together I will track all material with absolutely no plugins operating. The track I'm recording is run through my interface's digital mixer before going to Logic.

In other words I don't polish until all tracking is finished.

For MIDI if I'm using huge 24bit piano samples for the final, I'll find a cheesy piano sound to track with and make changes once the track has been sequenced.

That's what I've found works well. Even if you have the sweetest fastest supercomputer around, latency is (for now) a fact of life with digital recording. I still use a G4 powerPC for most of my tracking. I had to go back to using OSX 10.4 but after taking it back in time a little bit, it's running as well as ever! I even ran V9 on it for a little while with no issues.

Good luck!
 
Peter Ostry said:
figgebass said:
internal latency within logic when routing/processing material it has not buffered which gives monitoring latency while recording audio. 🙁
... In protools it never enters the computers processing but stays on the protools dsp's. Is there a native card with dsp's?
Click to expand...
There are interfaces with DSP but they still employ an A/D conversion plus little time for routing/processing plus a D/A conversion. Although this system is called direct monitoring by the interface manufacturers, it is not direct at all. It can be called "low latency monitoring". The latency is really low and acceptable for most people. All modern interfaces from the mid-range upwards support this type of monitoring. I would say that bus cards have the potential to be the fastest, then Firewire, then USB. This may not be true forever.

But since you say that you are extraordinary sensitive to latency you may consider to go one step further and eliminate all latency of your recording path. Therefore you split the recording signal either after the mics and instruments or after external preamps and other hardware you may use, but before the audio interface. Monitoring is then be done through analog hardware only and practically latency-free.

Below is a drawing of the system I use myself. I work with mics, real instruments and software instruments and had always problems with latency until I changed the whole system:

20091115-8f77t3gxrm4acbtgrjr2nph64t.jpg

​

Be warned: If the interaction between the interface and the DAW is correctly set, nobody can blame the system if people don't play in time. It's all their fault because there is no latency in the path 🙂
Click to expand...

Thanx for the long answer.

yeah, I've thought about using a mixer, in fact I am on the way to pick up a Mackie Onyx 1640 just to try out what I can do with it and how it sounds etc etc , BUT the thing is I am looking for a very professional but also very compact system...one that I can carry in maximum 2 go's...My ideal setup would consist only of my stereo pre-amp, an a/d-d/a , my api summing mixer,headphone amp, my mac pro and my computer monitor.
IF I am to go into the mixer world then on top of adding a mixer I would have to add an outboard compressor for putting down vocals and an ampsim to be able to play guitar without just listening to the line signal...
Somewhere there it's starting to get a bit big for me....

Everything would be sooooo easy if Logic and Protools interacted in an acceptable way because then I'd have no latency that my brain detects and I'd have the possibility of using a compressor,for the singers and my listening pleasure, while recording and using an ampfarm or something like it to record guitar.
But the way it's been going these last few updates it seems that Logic and Protools will never be friends again....

So...again...does anyone know of an interface with onboard dsp for direct monitoring that has an ok amp-sim and compressor among its plugins?
 
I do have a question... I was just in the Studio working with PToolsHD that has a setting for latency compensation. "Even when tracking," the engineer explained, "The tracks will sit just a millisecond or two off from each other. It's not a big deal for one track but when you have several slightly off it can start to make things muddy and flat." Apparently this setting configures how much time things took to process and lays the tracks with that correction. He showed me the same sample one with and the other without. One sounded clear and wide and the other sounded slightly but noticeably cloudier. Does Logic have a setting like this?
 
Fr3ShiE said:
I was just in the Studio working with PToolsHD that has a setting for latency compensation. "Even when tracking," the engineer explained, "The tracks will sit just a millisecond or two off from each other.
Click to expand...
A millisecond is a bit too optimistic I think, but this short latency comes from ProTools hardware, not from routing through the computer and ProTools software. That's what we are talking about: Don't route through the software for monitoring.

Btw, I am pretty sure that the engineer didn't mean the tracks sitting 1-2 ms apart. The tracks should sit accurate. I guess he meant something else.
 
Thanks Peter!

He may have just been talking up his stuff because he knows I'm a Logic user and he's in the hot seat for not having our project done, we recorded in September. I have learned a lot sitting in on the mixing sessions this last week, also what's been reinforced here by you guys! I'm learning a lot, it's an exciting time for my music and recording. I did make a great couple connections with this project, looking forward to having a final product to peddle. I'm waiting for my new Ensemble to come in the mail; I just got rid of the other interface that glitched the first month. Moving from 16 ins to 8 but heck... Movin' on up!

😎
 
You can compensate globally for input record offset (positive or negative) using the "record delay" parameter in global prefs.

You can compensate for negative (early) input record offset on an input-by-input basis by creating an audio "input" channel object for the relevant input in the environment and applying a sample delay plugin - this delay will be recorded.

To compensate for positive input record offset on an individual input do the same thing, but delay all the other tracks.

I've used this technique to remove relative record offsets when recording via RME Fireface analog ins (which line up perfectly because the RME driver correctly reports the input latency) while also using external A/D converters via the Fireface ADAT in (which will have different, unreported, AD time, and so won't line up).

With care and correct measurement, you can also use this technique to adjust for perceived monitoring differences (ie what you HEAR is what you record) between true analog source-monitoring and hardware "direct" monitoring - the difference is typically 2ms or so.

The only thing to be aware of is that you should not monitor the record tracks through Logic, because that monitor signal will also be delayed by the Sample Delay plugin on the input.
 
Check the Audio Driver section, you can lower your I/O buffer size to get less latency. they'll always be some (on native rigs as opposed to TDM)
Good Luck.
Question figgebass,
using a mixer, or your hardware's internal routing of inputs feeding to its outputs,
why not record all audio data (and midi from a keyboardist) into Logic without software monitoring on, let the hardware/mixer feed the no latency monitoring to the musicians, and you catch everything into Logic. if you need verbs or delays to dress up the monitoring you could turn on software monitoring, mute the outputs of the tracks but only monitor the effects return from logic.
hope I'm making myself clear. The reverbs would theoretcally have a 5.2ms delay in them, but since its an effect the latency might not affect the performance.
 
Back
Top