Switch Settings, Crossover Mode Selector Switch

SWITCH SETTINGS

NOTE:

•Before switching each Selector Switch, turn off the power and insert a small screwdriver, etc., perpendicularly to the Switch.

Fig. 9

Fig. 10

Crossover Mode Selector Switch

a) Set to the “OFF” position when the amplifier will be used for driving full range speakers or when using an external electronic crossover. The full frequency bandwidth will be output to the speakers with no high or low frequency attenuation.

b) Set to the “ON” position when the amplifier is used to drive a tweeter/ midrange system. The frequencies below the crossover point will be attenuated at 12 dB/octave.

NOTE:

• In this case the maximum Bass EQ boost level is reduced.

Crossover Frequency Adjustment Knob Use this control to adjust the crossover frequency between 50 and 400 Hz.

Input Gain Adjustment Control

Set the PDR-V75 input gain to the minimum position. Using a dynamic CD as a source, increase the head unit volume until the output distorts. Then, reduce the volume 1 step (or until the output is no longer distorted). Now, increase the amplifier gain until the sound from the speakers becomes distorted. Reduce the gain slightly so the sound is no longer distorted to achieve the optimum gain setting.

Input Channel Selector Switch

a) This switch setting is for selecting either 2-channel or 4-channel input mode. When set to “1/2”, signal will be copied from CH-1/2 and sent to CH-3/4, eliminating the need for Y-adapters.

b) Setting this switch to “3/4” will keep both inputs, CH-1/2 and CH-3/4 independent.

A 4-channel source is required for this mode.

Subsonic Filter

The subsonic filter for cutting ultra low frequencies from the input signal before being amplified.

This is desirable for several reasons:

–To protect speakers too small or not capable of reproducing ultra low frequencies.

–To minimize power wasted from reproducing inaudible sound.

–To protect subwoofers in vented enclosures from over excursion below the tuning frequency.

9-EN

ALPINE PDR-V75 68-25285Z56-A (EN/FR/ES)

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