Fostex AP1020 - Manual (Page 9)

* General use amplifiers not containing a crossover network can
also be used for the low region or high region amplifier.
When Ap20909/2130 are to be used as a full range amplifier,
harmful sub-sonic frequencies can be cut off if the crossover
network selector switch is set to HIGH and crossover frequency
to 30Hz.
If a line transformer is to be connected, always set to HIGH
PASS (crossover network selector switch to HIGH) and crossover
frequency to 100Hz.
The speaker low region cutoff frequency will slightly change
depending on the line transformer used.
Block diagram
—7—
IN HA
HPF
LPF
LPF COMP / LIMIT
CLIP
SENSER
PA
ON / OFF
CLIP DC & LF
SENSER
OUT
PEAK LEVEL
IND.
LOAD
IMPEDANCE
SENSER
FAN MOTOR
POWER SUPPLY
HIGH
LOW
-30 ~ 0dB
Circuit inside
dotted square
not included in
Model AP1020
M
M
CHANNEL 2
THERMAL
SENSER
THERMAL
IND.
MONO
STEREO
H. OUT
L. OUT