Mackie Onyx Blackbird Owner'S Manual Download

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Onyx Blackbird

3. SIG/OL LED

This dual-colored LED will illuminate green when the

channel's input signal (at least -20 dBu) is present,
indicating signal (SIG). It will remain lit non-stop so
long as there is signal above -20 dBu present in that
channel.

This dual-colored LED will illuminate red when the

channel's input signal is too high, indicating a signal
overload (OL). This should be avoided, as distortion will
occur. If the OL LED comes on regularly, check that the
gain control [2] is set correctly for your input device.

4. HI-Z Switch (Ch. 1 and 2 only)

Engage this switch if you want to connect guitars

directly to the 1/4" line inputs.

Without this switch, you need to use a DI box first,

before connecting guitars. If these switches are not
pressed in, guitars will not sound good, particularly the
high frequency response.

Plugging a guitar into a lower-impedance line-
level input can result in the loss of high
frequencies, causing an unnatural and dull

sound. Normally, you must use a direct box between a
guitar and the interface’s input, which serves to convert
the impedance of the guitar from high to low. These
hi-z inputs make the need for a direct box unnecessary.
However: The hi-z inputs are unbalanced (when the
switch is in), so if you’re doing a live show and running a
long cord between the instrument and the Onyx
Blackbird (say over 25 or 30 feet), it is best to use a
direct box with a balanced output to avoid picking up
noise over the length of the cord.

5. LOW CUT Switch (Ch. 1 and 2 only)

Engage the low cut switch (often referred to as a

high-pass filter) to cut bass frequencies below 75 Hz at a
rate of 18 dB per octave. The low cut switch affects the
mic, line inputs and hi-z inputs.

We recommend that you use low-cut on every

microphone application except 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 the 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 your subwoofers.

6. 48V PHANTOM POWER and LED (Ch. 1 and 2 only)

Most modern professional condenser mics require

48V phantom power, which lets the interface send low-
current DC voltage to the mic’s electronics through the
same wires that carry audio. (Semi-pro condenser mics
often have batteries to accomplish the same thing.)
“Phantom” owes its name to an ability to be “unseen”
by dynamic mics (Shure SM57/SM58, for instance),
which don’t need external power and aren’t affected by
it anyway.

Press this switch in if your microphone requires

phantom power. (Always check the position of this
switch before connecting microphones.) A green LED
will illuminate just to the left of this switch to indicate
that phantom power is active. This switch only affects
mic channels 1-2.

Never plug single-ended (unbalanced)
micro phones, or ribbon mics into the mic
input jacks if phantom power is on. Do not

plug instrument outputs into the mic XLR input jacks
with phantom power on, unless you know for certain it
is safe to do so. Be sure the channel's gain control [2] is
turned down when connecting microphones to the mic
inputs when phantom power is turned on, to prevent
pops from getting through to the speakers.

GAIN

INPUT 1-2

DIRECT MONITOR

40dB

20dB

TO MON

GAIN

PHONES

MAX

MON

PH1

MONO