How to Relieve Your CPU Load in Mixing

When you’ve got a lot of tracks you’ve generally got a lot of plugins. Some plugins are absolute hogs when it comes to consuming system resources and before you know it, your processor is overloaded and your mix is choppy. It’s near impossible to make well informed decisions about what changes to make in your mix when playback isn’t smooth. More than that it’s difficult to keep engaged in your mix when it takes even a few seconds to open up every plugins interface. With all this in mind, let’s talk how you can relieve your CPU load in mixing.

CPU Load in Mixing

There are a lot of steps you can take to reduce your CPU’s load while mixing. Not all of these will apply to or be possible for everyone, but many of these will undoubtedly help.

Increase Buffer Size in DAW

The buffer size determines how quickly (measured in samples) it takes your computer to process the audio that you’re recording or playing back.

Increasing the buffer size means you’re giving your system more time to process the audio which is easier on your CPU and leads to less pops, stops, skips, etc.

The tradeoff is there’s a palpable delay the higher you set it between when you begin playback and actually hear something. With too much of a delay and it becomes more difficult to efficiently mix.

The best buffer size will vary computer to computer.

Many DAWs have a way to simulate putting a tax on your CPU so that you can adjust it in real time like Ableton Live.

To determine the best buffer size for you, turn the test tone on and set your CPU usage simulator to 80%. Pull the buffer size down until you begin to hear alterations and artifacts breaking up the smoothness of the sine wave that is the test tone.

At this point, dial the buffer size back up until it’s clean once again. If you’re still having issues when mixing, try bumping it up a little higher.

This finds that sweet spot between minimizing delay and the fastest buffer size your system can handle.

Use VST3 Plugins Over VST2.4

Running VST3 plugins in place of their VST2 counterparts can save your CPU while mixing.

One of the main differences between VST2 and VST3 plugins is in how they tax your CPU.

VST2 plugins “idle”, applying the same CPU tax uniformly when they’re on your track whether audio is playing or not.

Conversely, the major advantage to using VST3 plugins is that they only tax the CPU by processing when audio is playing on that track. Once the audio clip ends on the timeline, the VST3 essentially shuts off.

In other words, if the plugin isn’t being used at any point in time, it’s not eating up your system’s resources. This is much more efficient compared to having it run constantly whether you need it in that instant or not.

The next time you’re installing a plugin, if they give you the option for both VST2 and VST3, if you know your computer and DAW can run VST3 then opt for that.

Freeze Tracks

Freezing tracks in your set is a very effective way to save CPU load on tracks you already have more or less sounding how you want.

When you freeze a track, it locks that track as is with all of the plugin effects applied to it but without them burdening your CPU to the same degree as if the track was unfrozen.

When a track is frozen, you have limited access to it.

While you can’t adjust those plugins while the track is frozen, you can still pull the fader up or down, change the panning, etc.

If you’ve gotten a number of tracks sounding how you want, you can free up a lot of resources by selecting them all and freezing them in bulk.

Flatten Tracks

Flattening a track means taking that frozen track and essentially overwriting it, giving you a clean track with that audio on it.

The plugins disappear from the insert/chain, but the effects you had while the track was frozen get applied or “baked in” to the new track.

This saves more resources than just freezing the track. The only drawback is that you can’t change any processing after you flatten a track short of undoing it.

As such, make sure that you’re happy with your track(s) before you flatten them as you can’t go back later!

Use Resampling

Audio resampling is similar to freezing/flattening your track.

Here you’re printing one or more tracks with all of their effects to a new track.

The new track doesn’t have any plugins inserted, but the effects from the tracks you resampled from are baked in.

The main difference between resampling and freezing/flattening is that it happens in real time with playback and that you can select as many tracks as you want to combine them all into one. You also still have access to the original tracks which you can delete (or save your set as a new file name and then delete).

Using resampling, you can print your entire drum bus to a single track for instance, freeing up a ton of CPU load in the process.

You could also just render whatever tracks you want, then import those tracks and delete the old ones. It’s a different way of doing it, but both are essentially the same concept of locking in settings for multiple tracks and rendering it to fewer tracks.

Maximize Power Plan

Now let’s switch over to the computer side of things to help things run more efficiently. Doing any or all of these things will better equip your system to handle demanding project.

For instance, if you’re on Windows, consult this guide to change your power plan to force your computer to drive its CPU to the limit.

This can make a number of things on your computer run more efficiently and smoothly and this extends to your DAW.

Double Your RAM

I’ll mention this one because memory is cheap and when you’re running a lot of plugins, you can run short of RAM quickly.

Some higher demand plugins like Native Instruments Guitar Rig and virtual instruments like Omnisphere are RAM hogs.

I wasn’t even able to use certain drum kit presets on my last computer with Superior Drummer from Toontrack because all of the processing within the instrument was demanding 12GB of RAM on its own!

If you typically have a lot of plugins running and don’t have at least 16GB of RAM if not 32GB, this is likely a major cause of the bottleneck.

Considering you can double your RAM for $30 or less, there’s no reason not to max it out especially if you use your computer for audio mixing.

Close Resource Hogging Programs

I’ll state an obvious one, but don’t underestimate the demand certain programs have on your CPU or memory.

Web browsers in particular are a common memory hog. Sometimes you can have a daily virus or malware scan going without realizing it while you’re mixing and that’s slowing things down.

All this to say, be aware of the programs you have open while mixing and specifically their impact on your limited resources. In Windows you can pull up the Task Manager and click “More Details” and see the CPU and Memory impact of every program you currently have open.

I’ve got the aforementioned Superior Drummer preset open at the moment and you can see it’s pushed Ableton to the top of the memory consumption tab.

One more tip related to the Task Manager in Windows, click on the “Startup” tab to see which programs are starting up with Windows.

This shows everything that’s automatically opening with Windows and an estimation of their impact on your system. If you don’t pay attention to this, odds are you have a number of programs opening with Windows that you don’t often use. And if you DO use them, you can just as easily open them when you need them.

Disabling everything except the bare essentials which are required to keep your computer running can make your computer run much more smoothly the next time you restart.

Run a Virus/Malware Scan

You never know when some spyware, malware, or even a virus is affecting your system’s performance. It’s not always about corrupting your system, sometimes it’s just about jamming it up and slowing it down.

I run the free versions of Avast and Malwarebytes on occasion to both keep my system secure as well as running efficiently.

Going back to the last point, you don’t need to leave these programs open most of the time. Just run them as you need them then disable/close them until you need them again.

Defragment/Disc Cleanup

More housekeeping for Windows to keep your system running as efficiently as possible which will in turn keep your DAW running as fast as possible.

It’s a good idea to run the Disc Cleanup and Defragment utilities every month or so to keep your system’s files and folders organized on the backend so everything can be recalled more quickly.

Speaking of which, while RAM plays a larger role, an SSD can be marginally faster than an HDD. I like to keep Ableton Live on my SSD then keep the actual sets on an HDD.

Do a System Refresh

A system refresh takes your computer back to the day you got it before the registry got all cluttered with a bunch of programs you likely don’t even use anymore. I like to do this every couple years or so to ensure my system runs as quickly as possible and prioritize/reinstall only the programs I actually use.

Make sure you create a backup if you do this if you decide you change your mind in the future, but this is an easy and the most effective way to get your system to its most efficient state which pays big dividends for mixing.

When you’re reinstalling your plugins in this case, you can opt for the VST3 versions this time around to keep things efficient as well as plan for the future.

CPU Mixing Tips

• If you’re experiencing skips or freezes on playback while mixing and are being notified in your DAW that your CPU is reaching its limits, there are things you can do in your DAW and out of it.
• In your DAW, try increasing your buffer size, replacing your VST2 plugins with VST3 instances when possible, and use freezing, flattening, and resampling to keep the effects while minimizing the impact of those plugins on your system.
• Outside of your DAW, maximize your power plan, increase your RAM, close non-essential background programs, sweep for a viruses and malware, and run utilities to keep your system running efficiently. If all else fails in extreme cases, do a system refresh.