Providing a quality mix to performers on stage can be the difference between a memorable performance and a forgettable one. Proper monitor setup on stage allows musicians to perform with confidence, and perfecting that setup for large and small venues alike is the main goal of a good sound engineer.
Run your stage instruments into a Direct Injection (DI) box if they need to be balanced. Many instruments, such as guitars, basses, synthesizers and electric pianos, produce high-impedance signals that are unbalanced and can produce hum in the mix if they are connected directly to the front of house (FOH) mixing console. Run a ¼-inch cable from the output of the instrument or its amplifier to the input of the DI box. Repeat as necessary.
Connect your DI boxes and microphones to the FOH mixer. Use ¼-inch cables from the output connectors on the DI boxes and run them to open channels on the FOH mixing console. For vocal, amplifier and instrument microphones being used on stage, you may connect directly to the mixing board using XLR cables.
Determine the number of stage monitors and the placement you need. Providing a monitor for every musician on stage is optimal, but is not always practical given a venue size or the equipment available to you. Vocalists should always have a monitor and persons playing melodic instruments should at least be able to hear the stage mix with vocals. Most monitors are built with a 45 to 50 degree angle to the speaker cabinet, which is ideal for musicians who are standing. If a musician is sitting on stage, you will need to adjust the monitor’s angle so the sound is directed toward his head. Try to place monitors at least five to 10 feet apart.
Connect the output of the FOH mixing console to the monitors. Use a ¼-inch cable from the mixer’s output to send a full mix of all of the instruments to a monitor. Repeat for each monitor.
Adjust the mix going to each monitor. Each musician on stage will have an individual need for what is coming out of his monitor, so communication is key. Reduce the amount of the full mix coming through each monitor to the bare minimum the musician requires to cut down on a cluttered sound on stage.
Using equalization at the mixing console will improve the musician's ability to hear the monitor on stage.
Monitors that are not directly behind microphones could cause unwanted feedback.