Universal Audio Apollo Software - Manual (Page 28)

Apollo Software Manual Chapter 3: Console Application 28
Low Cut Filter
When enabled, the channel’s input signal passes through a low cut (high pass)
filter. This 2nd-order coincident-pole filter has a cutoff frequency of 75 Hz with a
slope of 12 dB per octave by default (the filter can change
when Unison is active
in the channel).
The Low Cut filter effects the Mic, Line, and Hi-Z inputs. Low Cut is typically used to
eliminate rumble and other unwanted low frequencies from the input signal.
Unison Parameter
The low cut filter is a Unison parameter that interacts with Unison plug-ins inserted in
the PREAMP slot. See the Unison chapter for more information.
48V
When enabled, the 48V button is red and 48 volts of phantom power is supplied
to the Apollo channel’s rear panel Mic input. Most modern condenser micro-
phones require 48V phantom power to operate. This option can only be activated
when the Mic/Line switch is set to Mic.
Depending on the current configuration of the Apollo and Console, there may be a delay
when changing the 48V state to minimize the clicks/pops that are inherent when engag-
ing phantom power. The +48V LED on Apollo’s front panel will flash during any delay.
Unison Parameter
48V is a Unison parameter that interacts with Unison plug-ins inserted in the PREAMP
slot. See the Unison chapter for more information.
Pad
When enabled, the PAD button is yellow and the channel’s microphone input sig-
nal level is attenuated by 20 dB. Pad does not effect the Line or Hi-Z inputs.
Pad is used to reduce signal levels when overload distortion is present at low
preamp gain levels, such as when particularly sensitive microphones are used on loud
instruments, and/or if the A/D converter is clipping.
Unison Parameter
Pad is a Unison parameter that interacts with Unison plug-ins inserted in the PREAMP
slot. See the Unison chapter for more information.
Polarity
When enabled, the polarity (aka “phase”) button is yellow and the input chan-
nel’s signal is inverted. Polarity affects the Mic, Line, and Hi-Z inputs.
Polarity inversion can help reduce phase cancellations when more than one mi-
crophone is used to record a single source.