How to choose an audio interface - a beginner's guide
If you have just decided to get into computer recording, or to upgrade from the 'just interested' level, you might easily be confused by the range of interfaces available.
But we can get rid of a whole load of possible choices quite easily - don't pick anything that isn't sold into the professional audio market.
So anything you see in a computer magazine is likely to be for general hobbyist use and won't give you the sound quality and reliability you need.
Likewise, some manufacturers have ranges of products that look more like toys than equipment capable of serious professional work. Granted, some might have good performance, but which? It's a confusion you don't need.
You wouldn't have to look through many recording magazines to see which manufacturers' names crop up most in professional work. Choose one of those manufacturers. To choose a manufacturer that doesn't seem to get mentioned in a professional context would clearly be the wrong thing to do.
Let's pick a reputable manufacturer - there are several, but I'll pick just one among near-equals - Mark of the Unicorn, also known as MOTU.
Audio interfaces are the heart of MOTU's business. If MOTU doesn't make good interfaces, it will go bust. That gives them a reason to care.
At the lower end of the MOTU product range is the Ultralite, which connects to your FireWire socket and runs from bus power. The number of inputs is significant. The Ultralite has two microphone inputs and six line inputs. With just two microphone inputs, you are clearly not going to be recording a whole band playing simultaneously. You could buy an 8-channel microphone preamplifier, but I suspect this is not the intention of this unit. There is also a two-channel S/PDIF digital input, making a total of 10 inputs with 8 analog and 2 digital outputs (plus headphones).
The Ultralite works at up to 24-bit resolution with a 96 kHz sampling rate. This is considered to be the professional standard these days, although many people use the 16-bit/44.1 kHz format for multitrack recording because it is possible to get more tracks and plug-in processing.
The Ultralite seems good, so what would persuade you to pay more for a supposedly better interface?
The answer is to be found in the MOTU 828mkII, which costs a little more but is more flexible. Audio resolution is unchanged at 24/96. There are two microphone inputs as before, but there are now 8 analog line inputs, and an additional 8 digital inputs on an ADAT-format connector. There is a stereo S/PDIF input too.
Outputs on this unit include 8 individual analog channels, 8 digital ADAT-format outputs, S/PDIF, 2 main outputs and headphones, making 22 in all.
The likely use of this unit, I suspect, will be with an 8-channel microphone preamplifier. Or you could use two 8-channel mic pres giving 16 mic inputs, providing one preamp had an ADAT-format output (such as the Focusrite Octopre LE with the digital option).
More money to spend? Then consider the MOTU 2408mk3. Although the onboard mic preamps have disappeared, you get 8 analog inputs and outputs (plus monitor outputs) and 24 digital inputs and outputs in ADAT or Tascam format. So with this unit and three digitally equipped 8-channel mic preamps, you can indeed record a whole band. A whole orchestra in fact.
I don't have space to list all of MOTU's audio interfaces - I did say it was the core of their business, that's why there are so many models - so let me skip all the way to the most expensive.
The MOTU HD192 ups the sound quality stakes and is capable of recording in 24-bit resolution with a sampling rate of 192 kHz. Currently, this is the best you will get anywhere in pro audio.
Of course, with this increased data rate, something has to give. And that is the input/output count. The HD192 has twelve analog inputs and twelve analog outputs on XLR connectors. You can use multiple interfaces to achieve more tracks, if your computer is fast enough!
Choosing an audio interface doesn't have to be rocket science...
- Choose a manufacturer with a reputation in pro audio.
- Decide how many analog inputs and outputs you want.
- Decide how many digital inputs and outputs you want.
- Decide whether 24/96 is good enough (it's more than good enough for most people), or whether you really must have 24/192 capability.
Done that? Get out and buy one and start recording!
Although MOTU's interfaces are pretty much an industry standard, the one thing they don't do is give you access to Pro Tools software. For that, you need a Digidesign or compatible M-Audio interface.