Excessive UAD Latency in Pro Tools on 2019 iMac

[[email protected]]

Does anyone have heavy latency problems with UAD-2 plugins in Pro Tools? I'm running a UA Apollo Twin X Quad and Octo Satellites DSP with a 2019 iMac 3.6 GHz 8-Core Intel Core i9, 128 Gb RAM, 5TB SSD machine. It is an SSD Fusion drive with PCI Express - both drives are SSD.
Even putting one plugin on a track in an empty session brings a crazy amount of samples latency in PT Delay Compensation. The SSL E 4K Channel Strip for example is at 2103 almost 40 times what the UAD Latency Values Table. It's not every UA plugin just certain ones. I've tried Pro Tools 2024.3.1, 2024.6 on Ventura 13.6.7 and Sonoma 14.5.

Does anyone either have a similar setup or know what could be happening?
Is this a Fusion drive problem, Thunderbolt Buss issue with this iMac, or something else??

Thanks

[Darryl Ramm]

This will all be working as expected, so likely a user understanding issue, and there are multiple things to understand here. UAD DSP plugins in DAWs are terrible for latency, they are significantly more latency and often more hassle than native plugins.

The latency you are looking up in that table is the additional latency within the plugin. You also have to account for the H/W buffer latency in getting out of Pro Tools over the damp string to the UAD DSP and back again. This stuff is explained in the UAD systems manual.

You should probably not be trying to use UAD plugins in Pro Tools for tracking, it's more intended for mixing, where this won't matter as long as it is withing limits ADC can handle. With the high latency of getting to the DSP you have very limited ability to run the H/W buffer at smaller sizes and keep all this stable.

If the UAD plugin are not used on a live input/motioning signal path then they will use the large playback buffer of 1024 or 2048 samples not what you set in the H/W buffer size.

This is the whole purpose for the Apollo Consoles and ability to run UAD DSP plugins in the console without this H/W buffer introduced latency.

Just running native plugins can get many users all they need for mixing and monitoring/tracking. Unfortunately the SSL 4000 plugins are not available in native from UAD.

If you want to monitor though this plugin while tracking you should be instantiating it in the UAD Console in your UAD Apollo Twin X Quad, not in Pro Tools.

[BScout]

As Darryl said. absolutely normal. Everyone who uses UAD plugins on their DSP platforms (Apollo, Satellite, etc) deals with it. The UAD native/Spark versions are better for that reason.

[musicman691]

I first saw this problem because the OP is using Superior Drummer 3 (which I use) and he thought it was a problem with that vi so he's staying ITB. Given that I have to wonder about his routing - plugins on a track with no audio routed to said track from within the session. Wouldn't that also be a factor which I think Darryl kind of mentioned. Also in his post over on the Toontrack SD forum he said he was running into the issue when mixing. He's not giving the same info here and on the SD forum.

Here's a link to the thread over on the SD3 forum but the issue is you have to have an account there to even just read the thread: https://www.toontrack.com/forums/top.../#post-3278035


Attached is a screenshot of his first message there. His name is Pete Risi

[s.d. finley]

OP- You are getting about 1000 SAMPLES MORE latency than I am getting on my MBP 2020 Intel, OSX Ventura, PT 2024.6 and UAD Arrow. Session is running off an external SSD. PT buffer size makes no difference in latency concerning UAD plug ins, which is expected. Maybe it's your routing?


edit- routing looks normal

[s.d. finley]

Originally Posted by Darryl Ramm

Can we maybe get off the repeating things like computer specs here. Audio latency in a DAW has nothing to do with what HDD or SSD a session is running off. Or any other computer specs. All that stuff determines if Pro Tools will run well/reliably at some load or crash or cause audio artifacts. Computer specs do not and have never directly affected a DAW latency. They indirectly affect some latencies by allowing sessions to run at smaller H/W buffer sizes or higher sample rates. And in the case of UAD DSP plugins and their signal path out and back into a DAW that buffering does matter.

The screenshot you attached shows 1143 samples of corrected latency. Where do you think the latency there above the UAD internal latency spec of 55 samples is coming from?

It is not clear from the screenshot if there might be other plugins etc., what the overall signal routing is, what the H/W buffer size, or sample rate is. How about mentioning those things that are much more directly relevant than stuff like computer specs.

And of course if you are mixing you never notice these latencies unless you run out of ADC headroom. And since UAD DSP plugin really are intended for mix use in a DAW I'm not following why this thread even exists. ADC should be correcting any latency... if it's not then speak up that might be yet another ADC/latency bug.

And I'll repeat a warning I keep making on DUC: It's easy to wrongly "misprove" H/W buffer size does not affect latencies when a signal path is not on a live input/monitoring path. In which case the relevant buffer size is the fixed disk aka playback buffer that is 1024 or 2048 samples depending on sample rate. You can change the H/W buffer size all day and it won't and is not expected to make any difference in those cases.

I have no other plug ins on this sessions. Only the single UAD plug in. The reason for the more than 55 samples is from UAD!! Its DSP is outside of PT. Where does UA even state that amount of latency for UAD DSP plug ins? In PT UAD has lots of latency. That is expected. OPs has almost twice as much as my latency. Why is that?

[s.d. finley]

Originally Posted by Darryl Ramm

I've explained the reason in my first post in this thread and then you post here saying that explanation is wrong saying this does not depend on the H/W buffer. Ah but then it's some other thing because the DSP is external. No the other thing *is* the H/W buffer (or playback buffer if being used) as I've already explained in this thread. Can you maybe in future read posts in a thread before replying.

The 55 sample is from the "Additional UAD Plug-In Latency" table in the UAD documentation that the OP was referring to. https://help.uaudio.com/hc/en-us/art...lug-In-Latency That's repeated in the printed doc as well and has existed for many years. That page explains these internal latencies are in addition to the latency caused by the H/W buffer. Ah yes the hardware buffer, the thing you just said this did not depend on. ¯\_(ツ)_/¯

For anybody to make numerical sense of what you are seeing vs what the OP is seeing I'll repeat again.... you need to know for both sessions the sample rate, H/W buffer size, and if this plugin is on a live motioning or playback signal path.

You don't use UAD in PT do you? Because if you did you would know that the UAD latency table is totally irrelevant in Pro Tools. I have been using UAD since UAD1 and it has always had terrible latency. UAD2 is better but still not good, for PT.

[s.d. finley]

Originally Posted by Darryl Ramm

No I don't use UAD DSP plugins, you know why... I don't want to deal with the high latencies while tracking. Or paying UAD for overpriced DSP glorified licensing dongles on top of already expensive (but good) plugins.

The UAD published latencies are not irrelevant in Pro Tools. That table is the "additional latency table" I've already pointed out exactly what the UAD doc explains how that is latency above the hardware buffer latency. What hardware buffer do you think they are talking about if not a DAW hardware buffer?

You are all over the place with your confusion here, maybe you can read the documentation carefully and do some tests and actually play with changing the H/W buffer size (with a live input, so your test means anything) and measuring latency. This stuff is not magic or witchcraft, it is well understood and deterministic, it has to be for ADC to work.

Wrong- you don't know about UAD plug ins and how they work in PT. The latency chart is correct for AU and VST but not for PT. Yes one would have to ADD the latency in the chart to the additional latency that is added by Pro Tools for the round trip of DSP in and out of the PT system. Look it up. Seriously. it's ok you don't know this as you don't use UAD at all or in PT.

[s.d. finley]

Originally Posted by darryl ramm

look it up where. Give a web link.

Actually i'm done with this stupidity, trying to explain stuff to a moron.

you are an eff *******

you are so full of yourself and won't admit when you have no idea what you are talking about. I have been using UAD for almost 20 years. F U

[musicman691]

Originally Posted by s.d. finley

Wrong- you don't know about UAD plug ins and how they work in PT. The latency chart is correct for AU and VST but not for PT. Yes one would have to ADD the latency in the chart to the additional latency that is added by Pro Tools for the round trip of DSP in and out of the PT system. Look it up. Seriously. it's ok you don't know this as you don't use UAD at all or in PT.

Originally Posted by Darryl Ramm

Look it up where. Give a web link.

Actually I'm done with this stupidity, trying to explain stuff to a moron.

Originally Posted by s.d. finley

you are an eff *******

you are so full of yourself and won't admit when you have no idea what you are talking about. I have been using UAD for almost 20 years. F U

Exactly. Darryl doesn't use UAD so that kind of removes him from being a be all/end all authority on them.