vermades said:
I see all these knobs on a mixer and i'm curious what exactly they all do. So you can adjust the volume, pan...for each channel..what else?, does it act as an equalizer as well? So if each channel say has 10 knobs..what are their purpose? enlighten me as I've never seen one other than in pictures and am a hardware noob.
I'm glad there is a noob forum so I don't feel like such a noob.
The basic function of a mixer is to take a large number of physical inputs, and create a smaller number of mixes, also called busses. These busses can then be routed to various physical outputs. Some mixers have a lot of flexibility in how the signals are routed, some mixers the routing is fixed.
On a typical inexpensive mixer, you might have the following busses:
- Master bus, variously called main mix, stereo bus, L-R, etc. Technically that is two busses, left and right. It is fed by the pan knob on each input channel, post-channel fader (meaning that the level of each input channel fed to the master bus is controlled by that channel's fader). The overall level of the master bus is usually controlled by a master fader, or a pair (L-R) of faders. The master bus feeds the main L-R output. Some mixers also have a seperate mono output which is the sum of the L-R busses.
- One or two Monitor mixes. These are fed by a monitor knob on each channel strip, which is typically pre-fader (meaning that the level of each input channel fed to the monitor mix is NOT controlled by that channel's fader, just the monitor knob). Each monitor mix will have either a master level knob or fader.
- One or more effects sends. These are fed by an effects knob, similar to a monitor send, but is normally post-fader. The effects send usually has a master level knob, and there will often be dedicated input channels for a stereo effects return. This bus is used to send whatever inputs you select to an outboard effects device, like delay, reverb, etc.
- Some mixers don't have dedicated monitor and effects busses, instead, they simply label them as auxiliary (aux) sends. In this case, each aux send or group of aux sends (1-2, 3-4, etc.) may be switchable as to whether it is pre- or post- fader.
OK, that's the basic mixing function. Mixers are set up with input channels on the left, and bus controls on the right.
Beyond that, mixers can also have:
- Microphone preamps on some, most, or all of their input channels.
- EQ controls on input channels. Some or all of these might be parametric, which means that the frequency center and/or width of the EQ is controllable.
- Onboard effects
- Built-in power amp (called a powered mixer)
- Headphone amp
- Graphic EQ on the master bus.
- Tape in/out controls (usually assignable to various busses, and fed by master bus)
- Analog/Digital conversion, or even Digital/Analog, usually on a digital mixer.
- Automation
- and much, much, more!! OK, maybe only a little more.
To get back to your original question, the layout of an input channel strip is typically:
- Mic/line input jacks
- Channel insert--allows you to send the input channel signal out after the preamp but before some or all of the other channel controls. The signal will be returned on the same jack (tip-ring-sleeve) back into the channel.
- Mic preamp control (level, trim, or gain). This may include switches for a pad (dB reduction) or polarity reversal (sometimes called phase).
- EQ
- Aux sends, with various assign switches.
- Pan control
- mute and solo switches. Mute is for killing the channel without having to move the fader. Solo kills all non-soloed channels.
- channel fader
- If you're lucky, you get a few LEDs on each channel as a level meter. If you're really lucky (and rich), you get a meter bridge with analog VU meters, although that would be at the top of the mixer.
The output section is just a bunch of faders and knobs to control levels, with some type of VU meter(s) and maybe a switch or two for assigns, the tape input, the onboard effects controls, the headphone amp . . .
