An 8-channel mixer is an electronic device used to combine multiple audio signals from individual sources. Unlike larger mixing consoles, which may blend 16, 24, or 48 individual signals, an 8-channel mixer is often used for much smaller applications, such as in home recording studios, lecture hall public address systems, or to mix sound in smaller music venues. Depending on the scenario, an 8-channel mixer may be used to optimize the limited feature set of a simple sound system or recording environment.
One scenario may involve mixing signals from eight individual microphones that will eventually be channeled to a singular monaural or stereo output. Each microphone may be assigned to individual vocalists, acoustic instruments, or amplified electric instruments that are seen in most popular music arrangements. During a live performance, the output from the mixer is sent to a powered amplifier and speakers, which enables this blend of sound to be clearly heard by the audience. In a home recording studio, the output from the device can be directed to the input channels of a stereo recording device.
An 8-channel mixer may include monaural or stereo input jacks with pre-amplified volume control, pan, equalization, and controls for effects such as reverb and delay. The mixer will contain a master control component, which includes the master faders, and send/return level controls for the effects attached to the mixer. Unlike larger mixers, the inputs are usually located on the left hand side of the unit and the master control section is on the right.
Each channel on an 8-channel mixer has an audio control called a potentiometer, a slide-style volume control fader which adjusts the channel's amplitude during the final mix down process. Each fader adjusts the channel assigned or one-half of a stereo signal, and only affects the signal level from one microphone or audio device. Each input channel consists of an input buffer called a trim or gain control.
Additional input channel controls adjust the signal's equalization by separately attenuating the bass, midrange, and treble. In smaller applications, equalization is often not a needed feature while mixing, so some small format mixers do not include an equalization component. Adjusting the equalization too much can overdrive the channel, resulting in an unpleasant sounding output signal. Lastly, balanced inputs, such as XLR or Tip-Ring-Sleeve (TRS) connectors, may be an option on an 8-channel mixer to reduce interference problems.