Onyx P
remium Analog Mix
er with Multi-
Tr
ack USB
Onyx Premium Analog Mixer with Multi-Track USB
14
15. Low Cut Switches
All channels with a mic input have a low-cut switch
(often referred to as a high-pass filter) that cuts bass
frequencies below 100 Hz at a rate of 18 dB per octave.
We recommend that you use low-cut on every
microphone application except kick drum, bass guitar,
or bassy synth patches. These aside, there isn’t much
down there that you want to hear, and filtering it
out makes the low stuff you do want much more crisp
and tasty. Not only that, but low-cut can help reduce
the possibility of feedback in live situations, and it
helps to conserve amplifier power.
Another way to consider low-cut’s function
is that it actually adds flexibility during live
performances. With the addition of low-cut,
you can safely use low equalization on vocals.
Many times, bass shelving EQ can really benefit voices.
Trouble is, adding low EQ also boosts stage rumble,
mic handling clunks and breath pops from way-down
low. Applying low-cut removes all those problems,
so you can add low EQ without blowing the woofers.
16. Line / Hi-Z Switch [Chs. 1 and 2]
To connect a guitar or bass directly to the mixer
without using a DI Box, press this switch in first;
then connect the output from the instrument
to the channel’s 1/4" TRS input. The input impedance
is optimized for direct connection and high-frequency
fidelity is assured.
In the out position, the channel’s 1/4" TRS input
becomes a line input just like the other mono line
inputs.
To use guitars or other instruments on other
channels, you will need to use an external DI box first.
Without the DI box – or if this switch is not pressed
in – guitars may sound dull and muddy.
-15
+15
MID
2.5kHz
OFF
ON
LOW CUT
HI
12kHz
LOW
80Hz
-15
+15
-15
+15
OUT
IN
100Hz
HI
12kHz
MID
FREQ
LOW
80Hz
-15
+15
HI-Z
LOW CUT
-15
+15
100
8k
1K
-15
+15
OUT
IN
100Hz
OFF
ON
OFF
ON
EQ
EQ
15
16
17
18
19
21
20
22
Channel Equalization (EQ)
All Onyx mixers have 3-band EQ with shelving hi,
peaking mid with adjustable mid frequency and shelving
low.
Shelving means that the circuitry boosts or cuts all
frequencies past the specified frequency. For example,
the low EQ boosts bass frequencies below 80 Hz and
continuing down to the lowest note you never heard.
Peaking means that certain frequencies form a “hill”
around the center frequency.
With too much EQ, you can really upset
things. We’ve designed a lot of boost
and cut into each equalizer circuit because
we know that everyone will occasionally
need that. But if you max the EQ on every channel, you’ll
get mix mush. Equalize subtly and use the left sides
of the knobs (cut), as well as the right (boost).
If you find yourself repeatedly using a lot of boost
or cut, consider altering the sound source, such
as placing a mic differently, trying a different kind
of mic, a different vocalist, changing the strings,
or gargling.
17. EQ In/Out
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 may
use this switch to make an A/B comparison between
the EQ'd signal and the signal without EQ.
The EQ circuits are based upon the designs of Cal
Perkins, an industry-leader in audio engineering
for over four decades and a long-time collaborator.
This “neo-classic” design provides the sweet musicality
of the British EQ sound, while still maintaining 15 dB
of boost and cut with optimum Q and minimum phase
shift (in other words, it gives you plenty of control
and is pleasing to the ear!).
The 3-band equalization has low shelving
at 80 Hz, mid peaking, sweepable from 100 Hz
to 8 kHz, and high shelving at 12 kHz. “Shelving”
means that the circuitry boosts or cuts all frequencies
past the specified frequency. For example, 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.
18. Hi EQ Knobs
The hi EQ provides up
to 15 dB of boost or cut above
12 kHz, and it is also flat
(no boost or cut) at the
detent. Use it to add sizzle
to cymbals, an overall sense
of transparency, or an edge
to keyboards, vocals, guitar and bacon frying. Turn it
down a little to reduce sibilance or to mask tape hiss.
+15
+5
0
+10
–15
20 Hz
100 Hz
1 kHz
10 k 20 k
–5
–10
