YAMAHA MG12XU MIXER

Band Rehearsal Setup Guide

Getting Sound Through The EV Powered Speakers

⚠️ IMPORTANT WARNING ⚠️

DO NOT REMOVE ANY CABLES FROM THIS MIXER

EXCEPT FOR MICROPHONE CABLES

The mixer is pre-wired to the speakers and patch panel on the OpenLIVE unit.

Removing other cables will require technical assistance to repair and will render the OpenLIVE recording unit useless. 


Before You Start

The mixer should already be connected to the EV powered speakers. You will only need to plug in your microphones and turn things on in the correct order.

Step-by-Step Setup

STEP 1: Starting Position - Set Everything DOWN First

BEFORE turning anything on, set these controls:

  • All white GAIN knobs (at top of each channel) → Turn fully LEFT (counterclockwise) to minimum

  • All channel FADERS (vertical sliders) → Push all the way DOWN to minimum

  • Red STEREO master fader (large red fader on right side) → Push all the way DOWN

STEP 2: Power On (IN THIS ORDER)

  1. Turn on the Yamaha MG12XU mixer (power switch on back panel)

The POWER indicator light on the front panel will light up green

  1. Turn on the EV powered speakers (power switches on back of each speaker)

The blue LEDs on the front of the speakers should light up

? TIP: Always turn the mixer on FIRST, then the speakers

This prevents loud pops that could damage your speakers or your ears!


STEP 3: Connect Your Microphones

You can connect microphones to channels 1-4 (the left-most channels):

  1. Plug microphone XLR cables into the MIC/LINE jacks on channels 1, 2, 3, or 4

These combo jacks accept both XLR and 1/4-inch connectors. Use channel 1 for lead vocals.

  1. If using condenser microphones, turn on +48V phantom power switch (top left corner)

The indicator will light when phantom power is on. Most studio condenser mics need this ON. Dynamic mics (like Shure SM58) do NOT need phantom power.

STEP 4: Turn On Channel Switches

For EACH channel you plugged a microphone into (channels 1-4):

  1. Press the ON switch (it will light up white when on)

  2. Press the ST switch (it will light up red when on)

STEP 5: Bring Up the Master Volume

  1. Press the STEREO master ON switch (bottom right - it will light up white)

  2. Slowly raise the red STEREO master fader to the '0' mark (about 3/4 up)

STEP 6: Set the Gain for Each Microphone

This is the most important step! For EACH microphone you plugged in:

  1. Have someone sing or speak into the microphone at performance volume

  2. Slowly turn the red GAIN knob clockwise (to the right) until you hear sound

  3. Keep turning until the red PEAK light above the channel flashes occasionally on loud parts

  4. If the PEAK light stays on constantly (not just flashing), turn the GAIN down a bit

✓ GAIN SETTING RULE:

Red PEAK light flashing occasionally on loud parts = PERFECT! | Red PEAK light staying on constantly = Too loud, turn GAIN down!


STEP 7: Bring Up Channel Faders

Now slowly raise each channel fader (vertical slider) to the '0' mark:

  • Start with all faders down at minimum

  • Slowly raise the fader for channel 1 to the '0' mark (about 3/4 up)

  • Then raise channel 2, then 3, then 4 to create your mix

  • The '0' mark (also marked 'U' for unity) is the normal starting position

STEP 8: Adjust Your Mix

Now fine-tune the balance between channels:

  • Push channel faders UP to make that channel louder in the mix

  • Pull channel faders DOWN to make that channel quieter in the mix

  • Use the red STEREO master fader to control the overall room volume

STEP 9: Fine-Tune with EQ (Optional)

If you need to adjust tone, use the EQ knobs on each channel:

  • HIGH knob → Adds brightness/clarity (cymbals, vocal presence)

  • MID knob → Controls body/fullness (guitars, vocals)

  • LOW knob → Adds bass/warmth (kick drum, bass guitar)

? EQ TIP:

Start with all EQ knobs at 12 o'clock (center). Make small adjustments. Turn LEFT to cut, turn RIGHT to boost.


When You're Done: Shutdown Procedure

⚠️ SHUTDOWN ORDER (IMPORTANT!) ⚠️

1. Turn off the EV powered speakers FIRST

2. Then turn off the mixer


  • Unplug your microphone cables

  • Leave all other cables connected to the mixer

Quick Troubleshooting

Problem

Solution

No sound at all

Check: 1) Are speakers on? 2) Is mixer on? 3) Is STEREO master ON switch pressed? 4) Is STEREO master fader up? 5) Are channel ON switches pressed? 6) Are channel ST switches pressed? 7) Are channel faders up?

Sound is distorted/fuzzy

Turn down the red GAIN knob. The red PEAK light should only flash occasionally, not stay on constantly.

Mic is too quiet

Turn up the red GAIN knob more. Check if +48V phantom power is on (for condenser mics). Make sure channel fader is at '0' mark.

Buzzing/humming noise

Check: 1) Are mic cables fully plugged in? 2) Is a guitar cable touching power cables? 3) Turn off ON switches for unused channels.

Loud squeal (feedback)

Turn down the channel fader or master fader immediately. Don't point microphones at speakers. Move mic away from speakers.


Need Help?

If you have any problems or questions:

  • Contact Grove Studios

  • Do NOT disconnect or change any cables except microphone cables


Grove Studios • Ypsilanti, Michigan

Happy Rehearsing!