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Installation Warnings and Tips:
• Disconnect the negative (–) lead from your vehicle’s

battery.

• At the installation sites, locate and make a note of

all fuel lines, hydraulic brake lines, vacuum lines
and electrical wiring. Use extreme caution when
cutting or drilling in and around these areas.

• Choose a safe mounting location away from moisture. 
• Make sure there is sufficient air circulation at the

mounting location for the amplifier to cool itself.

• Mount the amplifier, using the supplied hardware.

Specifications
• 225W RMS x 1 channel @ 4 ohms and 

≤1% THD + N*

• 360W RMS x 1 channel @ 2 ohms and 

≤1% THD + N*

• THD + N: 0.04% (rated power @ 4 ohms)
• Signal-to-noise ratio: 85dBA 

(reference 1W into 4 ohms)*

• Signal-to-noise ratio: 104dBA 

(reference rated power into 4 ohms)

• Frequency response: 20Hz – 330Hz (–3dB)
• Max power: 360 watts
* CEA-2006A-compliant

0 Speaker Output Connectors

• Connect the subwoofer to these terminals, 

observing proper polarity. Either + or – 
terminal may be used. Minimum total 
impedance is 2 ohms.

1 Fuses

• Replace only with the same type and rating.

2 Power Input Connectors 

• +12V: Connect to the positive terminal of the

vehicle’s battery. 8 AWG wire is recommended.
Install an appropriate fuse holder and fuse (60A
minimum) within 18 inches of the battery. Make
sure the wire is not damaged or pinched during
installation. Install protective grommets when
routing wires through the firewall or other sheet
metal. 

• GND: Connect to the vehicle’s chassis. Refer to

the picture below. 

• REM: Connect to the “Remote Out” lead from

the source unit or to a source of switched 
12V+ (ACC).

3 Aux Output Connectors (RCA)

• Nonfiltered pass-through output. Connect to the

input of an additional amplifier. 

4 Input Connectors (RCA)

• Connect to the RCA outputs from the source unit

or signal processor.

5 Input-Level Control

• Used to match the input level of the amplifier 

to the output level of the source unit. 

• See B for the adjustment procedure.

6 Low-Pass Filter Frequency Control

• 12dB/octave low-pass filter, 

variable from 32Hz to 320Hz.

• See C for the adjustment procedure.

7 DBO (Dynamic Bass Optimization) Variable

• For woofers in tuned (vented) enclosures, set

the Frequency control to a value 10Hz below the
enclosure’s resonance (tuned) frequency.

• For woofers in sealed boxes, set the control to

any value you prefer between 30Hz and 50Hz.

• Set the Boost control according to your 

preference, being careful not to apply 
enough boost to damage your woofer(s).

A DBO High-Pass Filter Frequency control,

variable between 10Hz and 100Hz. See
above for appropriate settings. 

B DBO Boost control provides up to 

12dB of boost slightly above the high-
pass filter’s frequency. See above for 
appropriate settings.

8 Remote Level Control (RLC) Connector 

• Connect the Remote Level Control (RLC) here,

using the supplied RJ-11 cable. 

9 Power On LED

• Illuminated when the amplifier is on.

A Protect LED

• Illuminated under any of the following fault 

conditions: battery over/under voltage, short 
circuit in speaker wires, amplifier is too hot,
amplifier’s output circuit has failed (DC voltage
is present in the amplifier’s output).

B Setting Input Level

A Turn Input Level control counterclockwise to

6V (minimim).

B With a dynamic music track playing, turn the

head unit’s volume control to the 3/4 position.

C Turn Input Level control clockwise until the

bass output is proportionate to the output of
the high-frequency speakers, according to
your preference.

D Input level is now adjusted correctly.

C Setting the Crossover

A Crossover setting for subwoofers.
Note: Acceptable frequency ranges are indicated 
in gray.

D Remote Level Control

The Remote Level Control, if installed, will allow
you to adjust the level of bass while seated in the
listening position.

4

 

 

1. Status LED on Amplifier not Lit - Head Unit (Source) Turned ON  

Verify: 

A. Remote turn-on wire from source to amplifier has proper voltage 

B. Power (B+) connections at amplifier, terminal blocks, and battery are secure 

C. Ground (GND) connections at amplifier and vehicle chassis are secure 

D. Battery B+ fuse (if used) is OK 

E. Amplifier fuse is OK 

F. B+ at battery and B+ at amplifier has proper voltage 

 

 

2. Status LED’s Lit, No Output from Speakers in Normal Operating Condition  

Verify: 

A. RCA cables from amplifier to source are securely connected 

B. Volume adjustment on amplifier is correctly adjusted 

C.  Source is ON and playing 

 

 

3. Engine Noise From Speaker(s) 

Turn source OFF, Disconnect RCA cables at amplifier. If noise stops, check equipment & cables leading 

to amplifier. 

Verify: 

A. RCA cables are of good quality with no breakage to internal shields 

B. RCA cables from source to amplifier are not run alongside any power cables 

 

 

4. Amplifier Output Distorted Music 

Verify: 

A. Source output music to amplifier is not distorted 

B. Source output sensitivity is correctly adjusted 

 

 

5. Amplifier Shuts Down, Green LED’s are Lit  - Amplifier is in Thermal Protection Mode 

Verify: 

A. Amplifier is mounted with adequate air circulation around heatsinks or vents 

B. Amplifier is not mounted under carpet or sealed enclosure 

C. Speakers meet correct impedance for application (mono or stereo hookup) 

 

 

6. Amplifier Does Not Turn ON, and Red LED is Lit Amplifier (and not Connected to a Shorted Speaker) 

Verify: 

A. Speaker crossover (if used) is not defective 

 

5

Front Plate

Standoff

Trans. Clamp

Trans. Clamp

1380-0003-00

RCA CAP (Red)

RCA CAP (Wht)

Part Number

Part Number

6

1

2

3

4

A

B

C

D

4

3

2

1

D

C

B

A

OP

OP

OP

OP

OP

OP

11

25

320

11

320

20HZ~100HZ

AMP

SPEAKER

BALANCED
INPUT

UNIT

BALANCED
INPUT
UNIT

GAIN CONTROL

BASS BOOST
VARIABLE

0dB--12dB/20HZ~100HZ

MODEL   FREQ
VARIABLE   LP

11HZ--320HZ/12dB

MAIN  AMP

FRONTL

2ohm/4ohm

AUX    OUT   L

AUX    OUT   R

+

-

Battery

+VCC

-VCC

+V

-V

POWER   SUPPLY

7