Alesis MultiMix12FX, Reference Manual

Page: 23 / 47

2 A Tour of the MultiMix
21
In this chapter, you’ll learn all about the MulitMix’s components
(except for the digital effects processor, which is explained in the
next chapter). Please refer to the diagrams as you read each section
to see which components we’re talking about.
Patchbay
At the rear portion of the top of the Multimix, you’ll find the
patchbay. This is where you plug in instruments, signal processors,
multitrack recorders and other devices. Whatever you need to
connect to the mixer, this is where it’s done. In the following
paragraphs, we tell you all about the inputs, outputs, switches and
knobs you see in this section of the mixer.
Mic Inputs (Channels 1 – 4)
The MultiMix uses standard XLR-type mic inputs. These provide
+48V phantom power that you can turn on and off with the
Phantom On switch located on the rear of the mixer. You
probably will have to turn on the phantom power when you’re
using most condenser mics, as these usually require the extra
voltage (unless the mic has its own power source, such as a
battery). Dynamic and ribbon mics don’t require phantom power
and are unaffected when the power is on.
These high-quality mic inputs also feature up to 50dB of preamp
gain that you can adjust with the Gain knob.
Another useful feature of these mic inputs is a high-pass filter
(HPF) that can be turned on and off with the HPF switch. When
you activate this switch, all frequencies below 75Hz are cut from
the signal. This is useful for mic or line signals that don’t have
much bottom end, such as vocals, snares, cymbals and electric
guitar. You’ll want to leave this inactivated for instruments like
basses and kick drums.
Line Inputs (Channels 1 – 4)
The line inputs, marked LINE IN, are balanced 1/4” jacks that
offer the same 50dB of preamp gain and the high-pass filter
provided by the mic inputs (however, phantom power does not
apply to line inputs). These inputs accept line-level instruments
such as keyboards and drum machines. If you find that your
instrument has a weak line signal, just plug it into channels 1 – 4
and crank it up with the Gain knob.
Although chances are your
microphones will work fine
with these mic inputs, we
recommend that you do some
checking up on the type of
microphone you’re using,
especially if it’s one of the
older vintage models. Verify
that your microphone
requires phantom power and
make sure its output is low
impedance, balanced and
floating.
Always connect your
microphones before
activating phantom power.
Microphones tend to be very
sensitive, and the sudden
power surge can do
permanent damage to the
mic’s circuitry. It’s also a
good idea to lower mixer
levels before you activate
phantom power.