Boston Acoustics GT-20 GT-222 Control Functions cont, Lowpass Crossover Controls, 7 “Q” Control

Control Functions (cont.)

6 Lowpass Crossover Controls

To use 12dB/octave crossover, move switch to right-hand position. Lowpass crossover frequency is adjustable from 50Hz to 350Hz by rotary control. (Moving switch to left-hand position will bypass crossover functions.)

7 “Q” Control

The “Q” Control is active when the highpass crossover is engaged and is cen- tered on the selected crossover point. The range of operation is 0.7–1.2.

dB

+1.6dB

0dB

-3dB

Q

.707 .95 1.2

t (tuned crossover frequency)

8 Status LED Indicators

GREEN indicates the normal operating condition; the amplifier is “ON.” GREEN and RED together are normal when the amplifier is first turned “ON”; RED will turn off after a few seconds. When both GREEN and RED remain on, the ampli- fier is in thermal shutdown condition. RED only indicates a fault condition, “SAFE.”

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