At the heart of any audio recording studio is an audio interface. These handy pieces of computer equipment convert instrument and microphone signals into a digital format that your computer can read, allowing you to record vocals and instrumentals straight into your DAW.
What are the differences between FireWire, USB and Thunderbolt audio interfaces? The differences between FireWire, USB and Thunderbolt audio interfaces primarily have to do with their connectivity. FireWire, USB, and Thunderbolt connections are physically different in their data transfer capabilities and latency specs.
The world of audio interfaces can be a confusing game. There's a wide variety of audio interfaces at different price points and using different technologies on the market. One of the main considerations to make is choosing the right I/O for your system.
Whether you are a home studio enthusiast or a pro engineer, there are three main types of audio interfaces used for different applications: FireWire, USB and Thunderbolt.
Which Type Of Audio Interface Should You Buy?
For many years, FireWire was the perfect audio interface I/O for Mac users – bringing exceptional performance, low noise floors and brilliant reliability. However, with Apple abandoning the port in 2012 (a common trend in that company), it has quickly fallen completely out of use.
That brings us to USB and Thunderbolt. USB is a universal connector that ensures your audio interface will work with virtually any computer. However, a relatively new option is the Thunderbolt 3 audio interface.
In this article, we'll walk you through all of the different types of audio interfaces out there today—FireWire, USB, and Thunderbolt—and help you figure out which is best for your setup!
What Is An Audio Interface?
An audio interface is an input-output device that effectively connects your computer to other audio devices.
In terms of inputs, audio interfaces are often able to accept microphones, external electric instruments (including guitars, basses, synths, etc.), outboard hardware (compressors, EQs, etc.), other interfaces, inserts, and more.
In terms of outputs, audio interfaces are often able to send to headphones, loudspeakers, amplifiers, other audio interfaces, recording gear, and more.
The audio interface acts largely as a hub and includes analog-to-digital and digital-to-analog converters to ensure audio is converted and sent where it needs to go.
The audio interface, along with the digital audio workstation, is an essential part of the modern recording studio.
To learn more about the essentials of the modern studio, check out the following My New Microphone articles:
• Top 7 Best Digital Audio Workstations (DAWs) On The Market
• Top 45 Must-Have Tools For Audio Recording/Mixing Studios
If you're using a USB microphone, chances are you don't need an external interface. This is because USB microphones have their own interfaces that let them talk to your computer and convert the analog sound signal into digital audio.
However, in the studio, we need an audio interface for hooking up XLR microphones and recording direct instrument inputs.
Furthermore, we should be using an interface for monitoring, whether that's through headphones or studio monitors.
• How Do USB Microphones Work And How To Use Them
• Are Microphones Input Or Output Devices?
• Are Headphones Input Or Output Devices?
• Are Speakers (& Studio Monitors) Input Or Output Devices?
FireWire: An Obsolete I/O
Developed mostly by Apple in the late 1980s, the FireWire port (or its boring, international standards name, the “IEEE 1394 interface”) was an extremely versatile port found on many older Mac computers during the late '90s and 2000s.
To understand why so many FireWire audio interfaces were made, we must remember that during this time, USB – the I/O that's now the default universal standard – was in its infancy.
Even when USB 2.0 became ubiquitous, many pros preferred FireWire over USB for its higher data transfer rates. For example, USB 2.0 could only handle 480 Mbps of data throughput, compared to the 800 Mbps FireWire 800 enjoyed.
However, the introduction of USB 3.0 in 2008 spelled the end of FireWire – as this next generation of USB standards brought in data transfer rates of 4.8 Gbps. By 2012, Apple had removed the FireWire port from all of their Mac devices.
Should you buy a FireWire audio interface today? Absolutely not. Even if you still have a Mac that supports it, any audio interface that uses this port will be old (lacking modern features of newer hardware) and will become useless when you inevitably upgrade PCs.
USB: The Universal Standard
The vast majority of audio interfaces available today use the USB standard. Computer manufacturers and audio interface makers were initially slow to adopt the USB 3.X standard. As mentioned before, this is precisely why FireWire interfaces stayed popular even after Apple began to phase the port out.
However, the landscape is vastly different today with entry-level audio interfaces like the Focusrite Scarlett Solo 3rd Gen (link to check the price on Amazon) using a USB 3.2 Type-C port. The main advantage of a USB audio interface is that it will work with any PC you plan to pair it with.
Focusrite is featured in the following My New Microphone articles:
• Top 11 Best Audio Interface Brands In The World
• Top 11 Best DAW Control Surface Brands In The World
• Top 13 Best Microphone Preamplifier Brands In The World
If you invest in a USB 3.X product, make sure that:
- Your PC’s motherboard supports USB 3
- You are plugging in your audio interface into a USB 3 port
This will ensure you're making the most of USB 3's data transfer rate. Why is this important for audio interfaces? The faster the I/O, the lower the latency of the interface.
Latency is essentially how fast the audio interface can send your signal to your computer for processing and also how fast this signal can be sent back to the device for audio output (headphones or speakers).
This is particularly important for live monitoring and using the interface at live events.
To learn more about latency, check out my article How To Fix Microphone Echo And Latency In Your Computer (7 Methods).
Thunderbolt: An Exciting New Paradigm
The latest development in audio interfaces comes with the widespread adoption of the Thunderbolt standard. Intel introduced Thunderbolt in 2011 as their high-speed alternative to USB 3.0.
The most recent iteration is Thunderbolt 3, supporting a data rate of up to 40Gbps. It is this step, however, that most accelerated the growth of the standard. Thunderbolt 3 uses the same connector as USB Type C, and therefore any Thunderbolt 3 port also supports USB Type C devices.
This has allowed the Thunderbolt 3 port to become the definite port – with Apple famously removing all other ports on the MacBook in 2016 in favour of it. This fact bodes extremely well for the futureproofing capabilities of Thunderbolt interfaces.
Thunderbolt audio interfaces have one main advantage over USB 3 products: decimated latency.
To compare the difference between USB and Thunderbolt, let's take two similar interfaces: the USB-powered Focusrite Scarlett 2i2 and the Thunderbolt Focusrite Clarett 2Pre (link to check the price on Amazon).
According to Reidys, the round-trip latency of the Thunderbolt interface is 1.67. This is compared to the 2.74ms latency of the USB Scarlett 2i2.
However, Thunderbolt interfaces are currently more expensive than their USB counterparts. However, the latency advantages we already see over USB products will justify the added cost for studio environments if your current PC supports Thunderbolt.
That's a big if. Thunderbolt is still proprietary to Intel and Apple (Apple Silicon included) machines. For studios using AMD systems, don't expect to see Thunderbolt 3 anytime soon.
Is there an open alternative to Thunderbolt 3? Yes – it's called USB4. The specifications for the standard were released in 2019. This standard uses the same connector as Thunderbolt 3 (and, by extension, USB Type C). Although, given how long it took for the industry to adopt USB 3.0, there's still a fair few years to wait until we start seeing USB 4 audio interfaces for the masses.