Another way to use the Low Cut filter
is in combination with the LOW EQ on
vocals during live performances. Many
times, bass shelving EQ can really ben-
efit voices. Trouble is, adding LOW EQ also boosts stage rumble, mic handling clunks, and breath pops. Low Cut removes all those prob-
lems so you can add LOW EQ without losing a woofer.
8. EQ IN/OUT Switch
This is a true hardware bypass of the Perkins EQ circuitry to insure that there is no coloration of the signal if the EQ is not needed. When this button is out, the EQ controls have no effect on the signal. You
LINE IN
(MONO)
L
BAL
OR
UNBAL
R
U
s’Owner
+15
+10
+5
0
20Hz | 100Hz | 1kHz | 10kHz 20kHz |
Here’s what the combination of LOW EQ and Low Cut looks like in terms of frequency curves.
can use this switch to make an A/B comparison between the EQ’d signal and the signal without EQ.
We have completely redesigned the EQ circuits in the Onyx Series of
GAIN
OUT EQ
IN
U
HIGH
12kHz
Manual
Low Cut with Low EQ Boosted
6.48V Phantom Power Switch (Channels 1-8)
Most professional condenser microphones require phantom power, which is a
mixers, based on the designs of Cal Perkins, an
engineering for over three decades and
U
MID
2.5kHz
U
LOW
80Hz
AUX
1
Dynamic microphones, like Shure’s SM57 and SM58, do not require phantom power. However, phantom power will not harm most dynamic microphones should you accidentally plug one in while the phantom power is turned on. Be careful with older ribbon microphones. Check the manual for your microphone to find out for sure whether or not phantom power can damage it.
Note: Be sure the MAIN MIX fader (38) is turned down when connecting microphones to the MIC Inputs, especially when phantom power is turned on, to prevent pops from getting through to the speakers.
7. GAIN Control
If you haven’t already, please read “Set the Levels” on page 5.
The GAIN control adjusts the input sensitivity of the mic and line inputs. This allows the signal from the outside world to be adjusted to optimal internal operating levels.
The | OO | MAX | |
shelving at 80 Hz, LOW MID peak- |
| 2 | |
ing, sweepable from 100 Hz to 2 kHz |
| ||
OO | MAX | ||
on the mono channels, HIGH MID |
| 3 | |
peaking, sweepable from 400 Hz to |
| ||
8 kHz on the mono channels (the | OO | MAX | |
|
| ||
single MID frequency is fixed at |
| 4 | |
2.5 kHz on the stereo channels), | OO | MAX | |
| PAN | ||
and HIGH shelving at 12 kHz. |
| ||
|
| ||
“Shelving” means that the circuitry | L R | ||
boosts or cuts all frequencies past | |||
|
| ||
the specified frequency. For exam- | Stereo Channel | ||
ple, rotating the LOW EQ knob 15 dB
to the right boosts bass frequencies starting at 80 Hz and continuing on down to the lowest note you ever heard. “Peaking” means that the frequencies around the center frequency are less affected by the EQ the further away they are.
9. HIGH EQ
If the signal is plugged into the XLR jack, there is 0 dB of gain (unity gain) with the knob turned all the way down, ramping up to 60 dB of gain fully up.
When connected to the 1/4" jack, there is 20 dB of attenuation all the way down, and 40 dB of gain fully up, with a “U” (unity gain) mark at about 10:00. (On the stereo channels, the GAIN range is
This control gives you up to 15 dB boost or cut at 12 kHz, and it is also flat at the center detent.
Use it to add sizzle to cymbals, and an overall sense of transparency or edge to the keyboards, vocals, guitar, and bacon frying. Turn it down a little to reduce sibilance, or to hide tape hiss.
+15
+10
+5
0
20Hz | 100Hz | 1kHz |
High EQ
10kHz 20kHz
Owner’s Manual
11 
