-Tuners and auxiliary equipment: Any auxiliary equipment capable of supplying a signal
between 316mV and 1V must be connected to the above mentioned LINE inputs.
- Headphones: In order to achieve the best performance, they must be of high impedance
type (200-600). They must be connected to the HEADPHONES OUT (33) connector, a standard
1/4" stereo jack. Connect ground to sleeve, ring to right and tip to left.
- Power amplifiers: See 4.10.2.
- Other mixers: The MIX (49) input provides a direct access to the main mix bus, so this is
a perfect input for another mixer to be plugged in without using up a regular input.
4. OPERATION AND USAGE
4.1. Start up
Power up the mixer by pushing the POWER (65) switch. The green pilot-light, integrated
into the switch itself, will immediately light up. Although the noise generated by powering up the
MAC90i is reduced to a bare minimum and is nearly null with the MASTER (19 and 32) faders down,
it is always advisable not to forget about this sequence: sound sources, mixer, equalizers, active
filters and power amplifiers. Power down the equipment by following the inverse sequence. This way
the peaks or transients produced by powering up/down a device does not affect the following one in
the audio chain and, as a result, they do not reach the loudspeakers, the weakest audio elements.
4.2. Monitoring
The MAC90i is equipped with an acoustical and visual monitoring system, through
headphones, CUE output and double VU METER. Switching on any of the PFL buttons, the signal(s)
present at the input(s) will be seen at the left VU METER. If no switch is at the on position, the signal
present at the main mix bus is heard (open faders). Switching on the OUT1/OUT2/AUX OUT
buttons, the signals present at the 1, 2 or auxiliar outputs are displayed in the right VU METER. If no
switch is on, the signal present at the main mix bus is displayed (open faders).
It is also possible to monitor through the CUE (46) output. This output carries the very
same signal than the headphones output does. Its nominal output level is -10dBV (316mV) and it is
controlled by the rotary knob CUE VOL (35).
4.3. Channel gain and equalization
These controls allow to individually adjust sensitivity levels and tone for every channel.
The GAIN (2) control provides a fine adjust of the input gain in order to make the ready-to-
mix signal's level match the playing channel's level. This operation can be visually performed through
the left VU METER, as well as acoustically with headphones, making successive comparisons
between both signals by means of the PFL buttons. The GAIN controls provide an adjust margin of
±20dB.
The tone controls for each channel allow a ±12dB adjust for the frequencies at 100Hz and
10KHz and ±15dB at 1.8KHz.
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