Does PT have the same I/O plugin behaviour as Logic?

[Ed Boogie]

Hi all,

In Logic, if you use the I/O plugin to integrate a piece of analog hardware, it puts the CPU load of the channel onto the last thread/core - almost like Logic is in 'live' mode. It also does the same with all master bus plugins - the master bus is processed on the last core.

So, having an I/O plugin on e.g. snare (along with other plugins), routed to a drum bus with several plugins on, then going to master bus with I/O plugin and other mastering plugins is a CPU nightmare. All the CPU hit from the snare channel, drum bus, and master bus is processed on a single core - this means you're going to have a lot of CPU spiking on that last core while the other 19 cores (in my case with an M1 Ultra) are chilling out.

In the above example, if you take the snare channel and output it directly to master bus (vs via the drum bus) the cpu % on the last thread will drop dramatically as the drum bus plugins are now no longer processed on that last core.

Does the latest version of PT have the same behaviour?

I'm wondering if this is a bad implementation from Apple or just the reality of having a ‘live’ I/O track in all DAWs.

If PT somehow allows me to integrate my hardware without this CPU hit, I would switch to mixing in PT! I want to use lots of I/O inserts but it doesn't seem plausible with my current workflow.

Thanks,

[tope d]

Originally Posted by Ed Boogie

Hi all,

In Logic, if you use the I/O plugin to integrate a piece of analog hardware, it puts the CPU load of the channel onto the last thread/core - almost like Logic is in 'live' mode. It also does the same with all master bus plugins.

So, having an I/O plugin on e.g. snare (along with other plugins), routed going to a drum bus with plugins on, going to master bus with I/O plugin and other mastering plugins is a CPU nightmare. All the CPU hit from the snare, drum bus, and master bus is processed on a single core - this means you're going to have a lot of CPU spiking on that last core while the other 19 cores (in my case with an M1 Ultra) are chilling out.

In the above example, if you take the snare channel and output it directly to master bus (vs via the drum bus) the cpu % on the last thread will drop dramatically as the drum bus plugins are now no longer processed on that last core. It's still much higher with the I/O plugin.

Does the latest version of PT have the same behaviour?

I'm wondering if this is a bad implementation from Apple or just the reality of having a ‘live’ I/O track in all DAWs.

If PT somehow allows me to integrate my hardware without this CPU hit, I would switch to mixing in PT! I want to use lots of I/O inserts but it doesn't seem plausible with my current workflow.

Thanks,

Hi Ed!
Welcome to the duc!
Will get back to you on this in a bit

[albee1952]

My thoughts"
1-to integrate hardware as an insert, Pro Tools doesn't use an "I/O Plugin". Instead, it uses a "Hardware Insert" plugin. This would be inserted into one of the 10 available plugin slots on any given track.
2-to use Hardware Inserts in Pro Tools, they must be configured on the Insert page of the IO setup menu. These insert paths MUST use matching IO on your interface. Example: say you have an HD IO box with 16 analog inputs and outputs; you would create hardware inserts pairing output 9 with input 9, output 10 with input 10, etc. The point here is that you can't just decide you want to send OUT thru output 15 and return the hardware on input 5(hope this is clearer than my description)
3-when you use Hardware Inserts in Pro Tools, depending on the hardware, you MAY need to add (manually) the proper delay compensation for the round trip out(thru D>A conversion) and back in(thru A>D conversion). This is not an automatic function(unfortunately), I just want you to be aware of the possibility for phase inaccuracy.

This may sound barbaric coming from another DAW, but consider that thousands of PT users are working with hardware inserts every day, so its not a deal breaker

[Ed Boogie]

Originally Posted by albee1952

My thoughts"
1-to integrate hardware as an insert, Pro Tools doesn't use an "I/O Plugin". Instead, it uses a "Hardware Insert" plugin. This would be inserted into one of the 10 available plugin slots on any given track.
2-to use Hardware Inserts in Pro Tools, they must be configured on the Insert page of the IO setup menu. These insert paths MUST use matching IO on your interface. Example: say you have an HD IO box with 16 analog inputs and outputs; you would create hardware inserts pairing output 9 with input 9, output 10 with input 10, etc. The point here is that you can't just decide you want to send OUT thru output 15 and return the hardware on input 5(hope this is clearer than my description)
3-when you use Hardware Inserts in Pro Tools, depending on the hardware, you MAY need to add (manually) the proper delay compensation for the round trip out(thru D>A conversion) and back in(thru A>D conversion). This is not an automatic function(unfortunately), I just want you to be aware of the possibility for phase inaccuracy.

This may sound barbaric coming from another DAW, but consider that thousands of PT users are working with hardware inserts every day, so its not a deal breaker

Thanks for the info! But how does the CPU usage work out for you?

I assume PT (all DAWs?) needs to process all hardware insert plugin chains on the same core? Indeed, thousands of professionals are hybrid mixing with hardware inserts and (I'm sure) mastering at the same time, but nobody seems to mention the single core CPU hit...

Luckily I have an M1 Ultra but all it will take is the 'next big thing' mastering plugin and I'm sure I'll have to go back to making compromises.

[Ed Boogie]

Originally Posted by tope d

Hi Ed!
Welcome to the duc!
Will get back to you on this in a bit

Thanks so much!

[albee1952]

Originally Posted by Ed Boogie

Thanks for the info! But how does the CPU usage work out for you?

I assume PT (all DAWs?) needs to process all hardware insert plugin chains on the same core? Indeed, thousands of professionals are hybrid mixing with hardware inserts and (I'm sure) mastering at the same time, but nobody seems to mention the single core CPU hit...

Luckily I have an M1 Ultra but all it will take is the 'next big thing' mastering plugin and I'm sure I'll have to go back to making compromises.

Just my opinion, but I think you are over thinking this. I'm running a lowly HP z4 with a 3.7GHz quad core and 32GB RAM and I have no issues working70+ track sessions. Of course, those that work in immersive or with hundreds of tracks will have different needs so maybe start by analyzing what your "real world" needs are. Nothing is future-proof, but I also expect plugin makers to make their plugins efficient As for CPU and cores, I never give it any thought as long as my setup continues to do everything I ask of it

[Ed Boogie]

On a current project, my last core/thread in Logic is up to about 95% and I'm on an M1 Ultra... it drops to about 50% if I output the snare to the main out vs the drum bus.

I don't think that's overthinking it... all it takes is a bit higher CPU usage on one plugin on the master and I'll be 'stuck'. I didn't spend £4k on a computer less than 18 months ago to start worrying about this stuff...

I'd wager that I have more 'mastering' plugins on the master bus than most.

Yes, I could change my workflow, but I don't particularly want to.

[K Roche]

I could be mistaken but I don't think PT uses any kind of plugin at all = I/O plugin or Hardware Insert plugin.
And so I am guessing there is no processing or CPU involved in Pro Tools when using hardware as an insert
Because for #1 it is not listed in the Plugin menu it is simply an I/O selection in the track inserts section (just like for example any mic pre channel, except it is routed thru the insert section instead of the track input section ) And there is no dropdown or GUI window with any kind of processing like volume, or ping, or latency correction like there is in the Logic I/O Utility. Which I think is listed in the plugins in logic ?

Again I could be wrong but in Pro tools I believe is it is simply a virtual path to route hardware into and out of Pro Tools Insert section.

For example here is the I/O "Input" tab for my system
And you can see my two 2 channel hardware units renamed 3U and M7 (channels 5-6 and 7-8 ) are shown as Inputs same thing on the Outputs tab and the Inserts tab

[Darryl Ramm]

There is CPU processing associated with any hardware insert, something has to bang the bits out to the interface and back in. It's notionally a minimal amount of processing and it's not doing anything like what software plugins do when they consume lots of CPU. The issue if there is one associated with inserts may well be hardware inserts forcing that signal path in the DAW into low-latency (and higher CPU use) mode that the OP alluded to.

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As for Logic, the hardware inserts via what Apple call the "I/O Utility" are not doing any heavy processing like heavy software plugins. Even if it might use the minimal AU plugin hooks to get the data streams and do things like gain adjustment on them its just not going to be a significant amount of CPU processing well not like a software plugin does. If adding an I/O utility appears to increase CPU load then you may be seeing an effect of Logic switching from large to small playback buffers, exactly the live input postulated about.

Pro Tools will run signal chain processing on a single core, seemingly up until a point. How all this behaves is very dependent on the workload, exact plugins (and how multi-threaded they are, etc.). Pro Tools is fairly aggressive about using high-latency buffers any time it thinks it can (which may be the source of some bugs). For example if you are running hardware insets in a signal flow that has no true live input/monitoring path it runs the insert through the high latency buffers, absolute latency then does not matter and Pro Tools ADC (Automatic Delay Compensation) correct for that not substantial buffer latency. I have no idea how well Logic does this for example, if for example the I/O Utility always throws plugin chains into low-latency mode that seems a mistake. But then I've never had any problems mixing I/O inserts with plugins in Logic or Pro Tools and never had to mess around working out what is going on. I don't load up mix busses with super-heavy plugins and if I do use heavy plugins elsewhere I will use freeze/commit to tame CPU usage. Being able to "commit up to an insert", including with hardware inserts in that stack is a very nice feature in Pro Tools. My general expectation from a Logic Pro user moving to Pro Tools is they might want to be prepared for more faffing around than they are used to to get a system running well/as good as it can.

Worrying about what ifs with complex systems is frequently not going to help, the things that will get you are often things you don't even know to worry about. You need to get your hands on Pro Tools and actually try using it yourself. When you install it make sure to do the systems optimizations, see "help us help you" up the top of every DUC web page. Make sure all your plugins are up to date and the AAX versions are ported to Apple Silicon (unlike Logic Pro Tools cannot run native on Apple Silicon and use Intel legacy plugins). Find some good tutorials online about using hardware inserts with Pro Tools and skim the stuff in the Pro Tools reference guide, unlike Logic Pro Tools hardware inserts need to be match I/O pairs on the interface. probably the most common cause of tears with the, second is not understanding latency/need to use ADC/how to handle interfaces that do not report the actual RTL latency and require some manual insert latency adjustment (unlike Logic and most other professional DAWs, Pro Tools lacks a hardware insert ping function).