Operation Manual

4 Channel Amplifier - Applications

MXB-480/MXB-4125/MXB-4175

One 4 Channel Amplifier in Mono/Subwoofer Mode with two Subwoofers

Subwoofer 4 - 8 Ohm

Subwoofer 4 - 8 Ohms

FILTER SELECT (CH1/2 & CH3/4)

• In Mono/Subwoofer-Mode select the Lowpass-Position (LOW PASS), which eliminates the higher frequencies. The

recommended crossover frequency ranges between 60 - 100Hz, depending on the size and response of the Subwoofers.

The Lowpass adjustment can be done with the LOW PASS control.

• In this configuration example the HIGH PASS control is not used.

INPUT LEVEL (CH1/2 & CH3/4)

• Turn the INPUT LEVEL controls on the amplifier to 4V position.

• Turn the head unit volume control to about 80-90% of its full setting.

• Turn the INPUT LEVEL controls clockwise until you hear some distortion.

• Then turn back the INPUT LEVEL controls slightly until you can hear clean sound.

BASS BOOST (CH1/2 & CH3/4)

• The BASS BOOST - Control increases the bass level at 45 Hz max. +12dB.

Caution! Please use the Bass-Boost carefully. The additional boost may result in clipping or overload.

INPUT SELECT

• The INPUT SELECT - switch must be in “2” - position.

Green: Left Speaker -

White: Left Speaker +

Black: Ground

Brown: Right Speaker +

Gray: Right Speaker -

HI INPUT

Connect RCA outputs from

head-unit with RCA inputs

(INPUT CH1/2).

Caution

Be careful not to connect speaker (-) to the ground or vehicle chassis.

Interconnect cable checklist:

• Connect the head unit line outputs with good quality RCA to RCA cables to the INPUT

CH1&2 of the amplifier.

• Connect the Subwoofers with the terminal blocks (SPEAKERS / + BRIDGED - from

Channel 1&2 and + BRIDGED - from Channel 3&4) of the amplifier.

•The minimum final speaker impedance must not be below 4 Ohm per channel pair. Too

low speaker loads result in too high heat dissipation and may cause the amplifier run into

protection.

• Please observe speaker channel and polarity as printed by the speaker terminal block.

Incorrect phasing of the speakers results in total loss of bass response.