So you’ve got the mix perfect, everything balanced, well placed and sounding just right – at least through your headphones. But how can you check your mix on external speakers or, even better, let others hear what you’ve created? This is when you need to hook your soundboard up to an amplifier.
This short tutorial will explain how to connect an external amplifier to a mixer. We will use an excellent basic mixer, the Yamaha MG10/2, and a great affordable amplifier, the Yamaha MA2120, as our reference, but all of these instructions can easily be applied to any other mixing board or amp.
First, we’ll explain the basics of connecting an amplifier and mixer together, then look at a few possible variations, and finally give some basic tips on how to make it all work and sound better, and some troubleshooting techniques in case it doesn’t seem to be working at all.
Connecting a Mixer to an Amplifier
An audio mixing board does not have enough power for speakers, so if you want to fill a room or reach an audience you will need to use an external power amplifier and PA (Public Address) speakers. Fortunately, connecting your audio board to an amplifier is quite easy and straightforward.
1. Check Type of Connectors
First, you need to check the type of connectors your sound board uses for its main stereo outputs, as well as what your amplifier uses for inputs. In our case, the Yamaha mixer uses mono female Phone plugs (see pic) and the Yamaha amplifier uses female RCA input connectors (see pic).
So for this example, you will need cables with male Phone jacks on one end and male RCA jacks on the other. You will need two of these cables – for the right and the left channels – and the cables need to be long enough to reach from the mixer to wherever the amplifier is positioned.
If you can’t easily recognize what type of connector you need, the owner’s manual will tell you, and the right cables should be readily available from the shop where you purchased your equipment, or from any pro audio retailer.
2. Plug Connectors in the Mixer
Turn your mixing board and amplifier OFF to prevent any damage or noise when connecting. Plug the right channel cable’s Phone plug into the mixer’s right channel output jack and the left channel cable into the mixer’s left channel output jack.
3. Plug Connectors in the Amplifier
Bring the other ends of the cables over to the amplifier and plug the right and left channel RCA plugs into the amp’s respective connectors.
4. Check Connection
Make sure that all volume controls are all the way down and then turn first the mixer and then the PA amplifier ON and slowly turn up the output level controls. If your amplifier is connected to speakers, and your mixer has an audio signal running through it, you should have sound!
Variation 1: Connecting to Powered Speakers
In some cases, you may want to use “active” loudspeakers. These are PA speakers which have a power amplifier built into them, eliminating the need for a separate amplifier.
Connecting your audio mixing board to powered speakers is exactly the same as connecting to an outboard PA amplifier. The same cables and connectors are used and the same principles apply, and you should be able to follow the directions above with the same results.
Some people want to connect their mixer to a guitar amplifier, but this is not normally recommended, as the output from the mixing board is too strong for the amp’s guitar input jack, resulting in unexpectedly high, even dangerous, volume levels, extreme distortion and damage to your equipment.
If your guitar amp has a line level input, you could safely use that instead of the main jack, but such a setup will never give you the same sound quality, will probably only be monaural (not stereo) and may not provide enough volume.
Variation 2: Connecting to a Home Stereo Amplifier
Connecting a mixing board to a home stereo amplifier is basically just like hooking the board up to a professional PA amp. A home amplifier probably uses RCA connectors, although some higher-end amps may have balanced XLR connectors as well.
Find an unused line level input on the back of the amplifier, like one for a tape deck or CD player. Never use the “phono” input, as this will cause distortion, unexpectedly loud volumes and possible damage to your equipment.
Follow the directions above, and make sure the amplifier’s source selection knob is set to the correct source (eg, CD player), and you should be good to go!
Please note that a home amplifier may also not provide sufficient volume, and may not be optimized for professional speakers or gear. While this option will work, it is almost always better to use even a more modest professional amplifier.
Variation 3: Connecting to Monitor Speakers /Amplifiers
This option is not for the main amp and speakers, but rather for the monitor speakers you yourself will use to listen to your mix (just like you do with headphones).
Everything else is the same, but instead of the main stereo outputs you would use the C-R Output jacks, and change the volume using the C-R / Phones level control. This allows you to use both main speakers and monitor speakers at the same time, and to change their volume independently.
What Jacks should I use to connect the Mixer to My Amplifier?
- Connect every microphone into the point box (snake).
- Connect every snake XLR connector to every mic input XLR connector.
- Connect the mixer main output to your picture equalizer input and join the picture output signal to your home power-amp input signal.
If you are not setting a graphical equalizer for your home speakers, then join the mixer master baits to the inputs of this power amp that pushes the speakers.
In order to avoid sudden loud noises and popping sounds, and even possible damage to your gear, you should always make sure all of your equipment is powered OFF before connecting or disconnecting anything, and that all volume controls are all the way down.
When you are turning your mixer and amplifier off, you should always turn the amp off first and then the mixer. When you are powering them back on you should reverse this, turning your mixer on first and then your amplifier.
Speaking of unwanted noise, cables can also be a major offender. The longer a cable is, the more noise it can pick up, and so cables should always be kept as short as possible. Use balanced XLR connectors whenever possible to eliminate noise, and try to keep all cables away from other gear, appliances or electrical wires. Keeping cables neat and separate from each other, instead of all heaped and tangled together – the infamous “cable salad” – can also make the signal much cleaner and the sound much better.
How Much Power
There’s a simple rule to know how much power your speakers need – determine their maximum recommended power and double it. This rule may sound unwise, but since you will never be clipping your amp or feeding a distorted signal into the speakers it can actually prevent damage, and the sound quality will greatly improve!
Adjust the Mix
The sound through your main PA speakers, in a larger space, will be substantially different from what you hear on headphones. Using the pan, equalizer and channel level controls, you can make the sound just right for the audience and the room, and eventually, you’ll even know how the right mix will sound through your ‘phones.
Troubleshooting – I’ve connected the amp to a mixer, but it doesn’t work. What should I do?
What if you have followed our instructions and aren’t getting any sound? Even the simplest process can go wrong, and finding the reason can sometimes take longer than the process itself. To avoid this, let’s run through some basic problems you might encounter.
- Make sure all of the equipment is turned on, and that the volume controls are turned up at least a little. This includes not just the main mixer and amplifier, but all the input channel level controls as well. Listen to your headphones to see if you are getting sound there.
- If you are, check the cables between the mixer and the amp, and the amp and the speakers. Make sure they are in the right place and that the connectors are secure.
- Check the fuses and circuit breakers. Sometimes a protection circuit will trip, cutting off power or audio signal, and you might just need to turn the equipment off for a moment to let it reset.
- If possible, connect each separate piece to other gear to see if it works, and replace cables with spares if you have them, and then you might be able to figure out which piece is causing the problem.
- You should NEVER open up any electronic equipment to try to diagnose or fix it or for any other reason. Doing so will void your warranty, might damage the equipment and can cause serious electrical shock and injury. If you can’t figure out the problem, bring it to a qualified – preferably factory authorized – technician.