How Many Mixer Channels Do I Need? Counting Inputs Before You Buy

In this guide:Counting · The forgotten ones · Outputs · Growth · Picks · FAQ

Channel count is the first number anyone looks at and the easiest to get wrong in both directions. Buy too small and you are patching things out mid-set. Buy far too large and you have paid for faders you will never touch, when the money should have gone on better speakers.

The method is simple: write the actual input list, add the things people forget, then add headroom.

Counting a real input list

Work through the stage, source by source, and write every one down. A typical five-piece function band looks like this.

That comes to somewhere between 18 and 24 for a band that describes itself as five people. This is the standard surprise.

The inputs people forget

• Playback, backing tracks and click.
• A spare vocal for a guest or a speech.
• A DI for a visiting act’s laptop.
• Talkback for the compere or the venue.
• Ambience or audience microphones if anything is being recorded or streamed.
• A feed coming back from something else, such as a video playback.

Add two spare channels beyond your count, minimum. They will get used on the first job.

What actually runs out first

Channel count is rarely the binding constraint. These are.

• **Aux sends**, one per monitor mix and one per effect. A band with four wedge mixes and two effects needs six before you have done anything unusual. See aux, group and matrix explained.
• **Physical outputs**, which are not the same as aux buses. A desk may have eight buses and only four XLR outputs.
• **Mic preamps** against line inputs. Some desks count stereo line inputs in their headline channel figure, and those cannot take a microphone.

Read the specification carefully: a desk advertised as 20 channels may be 16 mic preamps plus two stereo line inputs.

Buying for the next three years

• Count today’s list, add the forgotten items, add two spare.
• Check the aux and output count against your monitor requirement, not just the inputs.
• Consider whether a stage box or expander can add I/O later, which turns the decision from a replacement into an addition. See I/O expansion.
• Do not buy channels at the expense of speakers. An underpowered PA with a huge desk is the wrong way round.

Frequently asked questions

How many channels for a 5-piece band?

Typically 18 to 24 by the time drums, backline, vocals and playback are counted. The instinct to say “five people, so twelve channels” is where the trouble starts.

How many channels for a church?

It varies enormously, but a band plus a lectern, a roving handheld, a lapel and playback commonly lands between 16 and 32. Count the fixed inputs as well as the band.

Is it better to have too many channels?

A little spare is sensible, and a lot is money that should have gone into loudspeakers or monitoring. Two spare channels is a good rule.

Do stereo inputs count as one channel or two?

Two, in terms of what they carry, but desks vary in how they count them in the headline number. Check the number of mic preamps separately from the total input figure.