STK Professional Audio SP-112APM, Owner'S Manual, Page: 18 / 40

1. Internal and External level controls
Sets the volume of the amplifier channels. The Internal pot
adjusts the volume of the internal sub woofer.
The External level pot adjusts the volume of the external
speaker connector
2. Protect indicator
Some fault conditions may cause the output of the amplifier
to be muted. The protect indicator is normally off, but will
blink under below condition. Speaker output wires develop
a short circuit. The heat sink reach a limited working
temperature. If the AC Power voltage is higher than rated
power. If the amplifier output detected DC voltage.
3. Internal and external peak Indicator
The clip LED turn on when distortion is audible in the
amplifier output.
4. signal indicators
The signal LEDs turn on when a signal is present at the input
of that channel.
5. Internal channel input jack
This input is summed with the External channel input and
send signal to the Low pass filter.
SUB+SUB mode: This input is connected to the Internal
output connector through high pass filter and send signal
to the internal and external output Amps through low pass
filter. SUB+Sat mode: This input is connected directly to the
Internal throughout connector and send signal to the external
output Amps though high pass filter.
6. External channel input jack
This input is summed with the Internal channel input and
send to the Low pass filter.
SUB+SUB mode: This input is connected to the External
output connector through high pass filter. SUB+Sat mode:
This input is connected directly to the external through
output connector and send signal to the external output
Amps through high pass filter.
7. Mode selector switch
SUB+SUB mode: The internal input channel drive the
internal speaker. The External channel is fed from a Low
pass filter and should be used to drive a STK SP115S or
SP118SL passive SUB woofer speakers.
SUB+SAT mode: The internal channel drives the internal
speaker. The External channel is fed from a high pass filter
and should be used to drive a full range external speaker.
8. Polarity switch
After check sound environment, set the polarity of same
phase to your coupled speaker systems.
9. HPF SW(Low Cut filter)
The Low-frequency(LF) filter rolls of signal below 45Hz.
Improve bass performance by limiting sub-audio cone
motions, that making more power available for the speaker
8. Panel Descriptions
l
각 부의 명칭
17
INTERNAL SPK AMP
INTERNAL INPUT
EXTERNAL SPK AMP
EXTERNAL INPUT
INTERNAL EXTERNAL
4
13
5
6
12
9
10
1
2
3
8
7
1
1
SP-158AP / SP-1812AP
11 14
15