I need some clarification about recording with plugins and low latency.

[bashville]

Originally Posted by Drew Mazurek

Because of the change in PT11's fixed plugin buffer. It's always at 1024 or 2048 depending on sample rate.

When you change the buffer in 11, you're just changing the "input buffer".

This dual buffer concept is good for "regular" native plugs because they can switch back and forth between the two buffers based on whether a track is armed, in input mode, or playing back. UA plugs don't have that ability (currently) because they ALWAYS operate in the plugin buffer.

Hi Drew sorry to resurrect this old thread--but then why sometimes do CPU error messages in 11 and 12 still suggest setting the buffer size higher, if it only affects the input buffer?

Please see my other thread about this--thanks

http://duc.avid.com/showthread.php?p...61#post2249161

[Darryl Ramm]

Originally Posted by bashville

Hi Drew sorry to resurrect this old thread--but then why sometimes do CPU error messages in 11 and 12 still suggest setting the buffer size higher, if it only affects the input buffer?

Please see my other thread about this--thanks

http://duc.avid.com/showthread.php?p...61#post2249161

Increasing the input buffer size still helps reduce the load on/latency sensitivity on the overall system. And in many cases the direct processing errors will be happening with those input buffers. I would stop worrying about why the message is suggesting you to do something and just try it it, if it helps great, if not you have more trouble shooting to do. A few minutes of time spent to test is well spent.

[bashville]

Originally Posted by Darryl Ramm

Increasing the input buffer size still helps reduce the load on/latency sensitivity on the overall system. And in many cases the direct processing errors will be happening with those input buffers. I would stop worrying about why the message is suggesting you to do something and just try it it, if it helps great, if not you have more trouble shooting to do. A few minutes of time spent to test is well spent.

Hello again! If it helps me to mix once I'm done recording everything, then I definitely plan to raise that buffer size up and rock that mix. Believe me you're preaching to the choir about "gettin' her done!"

BUT maybe I want to record something at that low latency buffer setting. What happened to the separate input buffer? It's your first statement "Increasing the input buffer size still helps reduce the load on/latency sensitivity on the overall system" that I want an explanation for. Under what circumstances does it do that? It's not supposed to. It's supposed to be for the input buffer only. I appreciate the practical suggestion--I'd also like to know what's really happening.

[Darryl Ramm]

Originally Posted by bashville

Hello again! If it helps me to mix once I'm done recording everything, then I definitely plan to raise that buffer size up and rock that mix. Believe me you're preaching to the choir about "gettin' her done!"

BUT maybe I want to record something at that low latency buffer setting. What happened to the separate input buffer? It's your first statement "Increasing the input buffer size still helps reduce the load on/latency sensitivity on the overall system" that I want an explanation for. Under what circumstances does it do that? It's not supposed to. It's supposed to be for the input buffer only. I appreciate the practical suggestion--I'd also like to know what's really happening.

Changing the buffer size in the playback engine setting changes the so called input buffer. The smaller that buffer is the higher the chance of CPU and other errors. You seem to think that that buffer being set small won't/cant' cause problems. It absolutely can and will, that is exactly expected, the computer still has to struggle to shuffle around all those small buffers with very low latency that is why the error message are telling you to make them larger and take some load off the system, and make that "input" IO less latency sensitive.

So again, just try things. In the other thread I've also asked you questions about your setup. If you are getting IO related problems you need to carefylly check optimizations and all your IO setup. And your are on an old Mac Pro with SATA II/3 Gbit/s IO, so very slow compared to a modern Mac (or MacBook Pro).

If latency questions are bothering you, just start measuring stuff. You can set up a click track and route that via multiple internal buses/aux/tracks etc. and see the effect of different routing topologies. Just disable delay compensation while doing this. You can send that click out your interface and split it and bring it back into two (or more) channels and route them differently and measure there differences, try changing IO buffer sizes, inserting plugins on tracks, etc. and see the effects. You can share/split one input to multiple Tracks/Aux's in Pro Tools no need to physically split a cable. Show a sample ruler makes things easier to think about, and and put the Main Counter in sample display mode .. then you can just drag out a selection between two points in the edit window and read the time difference in samples in the counter display "Length". Start with a large/obvious buffer size like 512 samples, that is also different that the 1024 or 2048 sample possible values of the output buffer.

[hnoormohamed]

Just a question related to the latency in record mode; without any plug-ins I was still getting a small delay while tracking vocals. So I switched the buffer size to 512 instead of 1024. Would this have any impact on my overall mixing with all the plg-ins / while bouncing to a stereo track output?

Please let me know your thoughts.

Thanks,

Hanif

[Darryl Ramm]

I do not understand what/why you are asking exactly.

1024 and 512 are both large buffer sizes to track at and will have noticeable delay. You know the sample rate and can calculate that latency. Are you talking actual real time latency or ADC not working properly. And presumably you are monitoring through Pro Tools or are you using LLM?

You usually set a small buffer size while tracking for low latency and then set a large size while mixing, for more stability/capacity. I have no idea why you are asking about the buffer size used for tracking affecting mixing.

[Glenjb]

Originally Posted by bashville

It's your first statement "Increasing the input buffer size still helps reduce the load on/latency sensitivity on the overall system" that I want an explanation for. Under what circumstances does it do that? It's not supposed to. It's supposed to be for the input buffer only. I appreciate the practical suggestion--I'd also like to know what's really happening.

Input buffer changes the buffer size on audio tracks being recorded as well as AUX/Instrument tracks I believe. If this is true than it makes sense why a higher input buffer helps during mixing even if you are not recording anything.