How Many Inputs Do I Need on My Audio Interface?

How Many Inputs Do I Need on My Audio Interface

Audio interfaces are a big topic in music production. There are a lot of things to learn and much information to take in. Not only that, but there are a huge number of choices when buying them. It’s sometimes difficult to know where to begin.

One a question that comes up a lot is ‘how many inputs do I need on my audio interface?’. If you’re not experienced within the world of music production, the answer isn’t clear. Well, don’t worry, I’m here in to help.

In this article I’m going to talk about the different types of inputs, their purposes, the three types of recording levels you should be aware of, and help you decide how many inputs you actually need.

How Many Inputs Do I Need on My Audio Interface?

Audio interfaces come in a range of sizes and have a variety of inputs. How many you need really depends on what you plan to record. First you need to understand about the different types of inputs and the three levels we use for recording. Only then can you make informed decision about the number of inputs you really need.

Audio Interface Inputs Explained

Audio Interface Inputs Explained
Audio Interface Outputs Explained
  • Mic Input– For connecting and recording microphones directly into your audio interface.
  • Instrument Input – Used to connect and record instruments like a guitar or bass.
  • Line Inputs– Used to connect and record instruments like an electric piano, synthesizer, or for external audio gear.
  • MIDI Input – If you want to record MIDI notes, then you’d use this input to connect and record a MIDI keyboard. Most MIDI keyboards use USB connections nowadays. Some old synthesizer also use MIDI inputs.

Recording Levels

What did I tell you? Easy to understand. However, you should also be aware about audio levels to fully understand audio interface inputs. For recording there are three levels:

Mic level is the lowest level which is used for, you guess it, microphones.

Instrument level is in the middle and we use it for, drumroll please… instruments. But just to confuse you, not all instruments. We only use instrument level for low impedance level instruments like passive guitars or basses, which are not as hot as a synth for example. That brings use nicely to the next level.

Line Level is the hottest level. As mentioned above we use it for high impedance instruments like an electric piano, synth, or other external gear. This could include connecting a CD player, drum machine, external preamp, or outboard gear like a compressor, limiter, or sound effects unit such as a reverb or delay.

As you can see from the diagram the front inputs on a lot of audio interface can accept multiple level types. To select between the levels you simply just need to push a button and the input impedance will be changed.

What Do You Want to Record?

What Do You Want to Record

Now you know about the input types and different levels. The next thing to think about is what you want to record. That will determine how many inputs you need for your audio interface.

Audio interfaces come in a range of sizes, they can have as little as two inputs, all the way to 18+. You can even connect two together to expand your I/O configuration.

If you’re a guitar player, you may just need one or two. If you want to record a full band you’re going to need as many as possible. To record a drum kit alone, you at need at least 8 microphones. Then you have your guitars amp, bass amp, and microphone for the vocalist to think about.

Singer-songwriters will need at least two, one for their vocals and one for their acoustic guitar. Electronic music producers may rarely even use inputs, if they do everything through their MIDI keyboard, using plugins, and virtual synths/instruments.

So, you see, there really is no correct answer to how many inputs you need. The answer depends on your requirements. Just think about what you will be recording. More specifically, what will you be recording at the same time?

Maybe you only need one input when you’re home alone, but what if you invite your friends over? You may need a few extra for a keyboardist, bassist, or singer.

What Should I Look for in a Good Audio Interface?

Apart from how many inputs you’ll need, you also should consider what outputs you’re going use for headphones, studio monitors (speakers), or if you want to route audio to other outboard gear.

Build and sound quality are exceptionally important, the connection type (USB, thunderbolt), if any additional software is included, and of course, the price! A lot to consider? It certainly is.

Luckily for you though, there are a lot of brilliant audio companies manufacturing well-made, reliable, and budget friendly audio interfaces. The marketplace is full of competition, with numerous companies all trying to outdo each other, which is great news for you.

I’ve put together a details list of The Best Audio Interfaces for Every Budget to help you make the best decision possible. Please feel free to give it a read.