How to Make Music on Your Mac with Minimal Latency

Reduce Latency on the Mac for Music

Making music on the Mac is easier than it ever has been with many open source apps which allow you to multitrack. They layer up tracks of samples and virtual instruments and turn them into MP3s ready for listening or uploading to iTunes.

But can just anyone on any computer do this? It depends on how elaborate the music is. Music takes memory, and this goes doubly when the instruments you use eat memory like samplers.

In this article we look at what you need to make your music flow and not stop or judder because your machine is fast but just not fast enough.

I/O, I/O, It’s Off to Work You Go

Most computers are fast today, and the new Macs are the fastest the Mac has ever been. That goes without saying, but what also goes unsaid often is that in order to function perfectly, professional apps need a lot of system resources.

This means although you can buy a new Mac Mini and make some kind of music on it, you might find that when you start trying to layer up 24 voices to make a choir that everything comes down to a crashing halt.

Even with a top-of-the-line iMac or Mac Pro, you would be hard-pressed to have seamless playback of that many tracks simultaneously one-hundred percent of the time.

So how is it that professional musicians make amazing and complicated music on computers if it can’t be done? The answer is that it can be done, but you need a bit of hardware – a special sound card and I/O box to take the load off the CPU. Latency is the problem, and this fixes it.

First Find Your Box

I/O boxes range in price from cheap to expensive, depending on your level. If you are a beginner you can use M-Audio audio interfaces and some of the low-end Edirol boxes by Roland. Higher-end boxes are made by AKAI and Protools. (The name of the AKAI box is a joke. by the way. It’s called EIE I/O. Old McDonald clearly had an audio interface as well as a farm.)

The sky is the limit when buying an audio box, and the rule is as usual with pro kit; get the best one you can afford. A good thing to bear in mind is that whatever you need, good secondhand ones are always available on eBay. A good cheap secondhand box which is quite common is the Edirol UA-25. Although a little noisy, some say it’s good for hobbyists although perhaps not as good for professional sound work.


Usually these I/O boxes use a type of hardwired ASIO protocol and some nice sound card hardware to take the sound processing load off the CPU and let it get on with running your digital audio workstation (DAW) software, such as Audacity or Reaper.

ASIO (or Audio Stream Input Output) is a protocol for the fast driving of sound cards designed by German music software company Steinberg to provide high fidelity and “low latency.” In normal human language that means it makes them sound good, and it drastically reduces the processing time of sounds so they play without a noticeable delay.

Most I/O boxes additionally provide useful music business inputs not usually available on computers like dual function XLR plugs which are also ¼” phono jacks, both common on high-end microphones.


They often also feature MIDI out ports to control actual hardware synthesisers synchronized with the virtual instruments.


PC users can use ASIO4All to reduce latency on non-ASIO peripherals, but Mac users can rely on the Core audio driver to take care of any low-end (software-based) music production processing.

Fitting an I/O Box

Usually I/O boxes are USB devices. Back in the day they were also Firewire-based, but as USB has gotten so much faster, Firewire has fallen out of style and is no longer used.

Most of the time, you can just plug the I/O box into the USB, and it will be detected by the DAW software so you can select it for output. Sometimes you may need to install a driver for the box and reboot. Either way, installation is usually trouble-free and quick.

Most DAWs have a Preferences setting to direct the audio from the software to a specific device. This means you can set the system audio to the speakers and set the audio from the DAW to go through your I/O box and into headphones.

In our example, the old Roland Edirol UA-25 I/O box needs no drivers to work with Yosemite. Just plug and play. If you want to make the system sound come out through the box, open your System Preferences and choose Sound.


Select the UA-25 on both the input and output tabs.

Similarly with applications like Audacity, choose the UA-25 from the input output drop-down menus to the right of the toolbar.


Sounds like Perfection

Is it perfect? Of course not. Depending on the speed of your system and the amount of music and sample data you are trying to crush through your system, it will sometimes halt. Usually the overloads will be dealt with gracefully by the DAW software, and you will just get an overload warning. It’s rare that the DAW program will crash because of sample data overload.

But by and large, having an I/O box dealing with your sound makes everything a LOT smoother and more professional. With an I/O box installed you can load more tracks, have more sample data sloshing around and run many more tracks stacked up at once than you could before.

Have you had an experiences making music on your Mac? Share them with us in the comments below.

Phil South
Phil South

Phil South has been writing about tech subjects for over 30 years. Starting out with Your Sinclair magazine in the 80s, and then MacUser and Computer Shopper. He's designed user interfaces for groundbreaking music software, been the technical editor on film making and visual effects books for Elsevier, and helped create the MTE YouTube Channel. He lives and works in South Wales, UK.

Subscribe to our newsletter!

Our latest tutorials delivered straight to your inbox