Pyramid PB-1038GX Operation & User’s Manual

amplifier. This amplifier extends the Pyramid tradition into a totally new series of amps, designed from the ground up to deliver the power, performance and flexibility the modern car audio enthusiast demands. When you check the list of features offered by the PB-238GX, PB-638GX, PB-738GX, PB-1038GX, PB- 1838GX, you’ll know you made the right choice with a Pyramid Power amplifier.

PB-738GX/PB-1838GX 13 stereo input connections PB-738GX/PB-1838GX 12 speaker connections PB-238GX/PB-638GX/PB-1038GX table of contents mounting and installation 23 protection circuitry and troubleshooting 24 16-17 18 20 21-22 19 speaker connections PB-738GX/PB-1838GX high level mono input connections PB-638GX/PB-1038GX mono input connections PB-638GX/PB-1038GX high level input connections PB-638GX/PB-1038GX electrical connections PB-238GX PB-638GX/PB-738GX PB-1038GX/PB-1838GX 10-11 2/4 channel input connections PB-238GX 14-15 features and specifications PB-238GX 4-5 PB-738GX PB-1838GX 6-7 general features 2-3 precautions 25 PB-638GX/PB-1038GX 8-9

· 800W x 2 Bridged Output (400W x 2 + 800W x 1) · Dual Variable Hi/Lo Electronic Crossover Network · Dual Variable Bass Boost (0 - +18 dB @ 60Hz) · Variable Input Level (Gain) Control · Remote Turn On/Off · Gold Plated RCA Inputs · High Level MOLEX Inputs · Power ON LED Indicator · LED Protection Indicator · Remote Bass Boost · S/N Ratio: > 95 dB · THD: <0.04% · Thermal Protection · Overload Protection · Short Circuit Protection · Anti-Thump Turn-On · Tri-Mode Configurable PB-638GX High Performance 1600 Watt 4 Channel Bridgeable MOSFET Amplifier · 500 Watts x 2 Output · 1000W x 1 Bridged Output · Variable Hi/Lo Electronic Crossover Network · Variable Bass Boost (0 - +18 dB @ 60Hz) · Variable Input Level (Gain) Control · Remote Turn On/Off · Gold Plated RCA Inputs · High Level MOLEX Inputs · Power ON LED Indicator · LED Protection Indicator · Remote Bass Boost · S/N Ratio: > 95 dB · THD: <0.04% · Thermal Protection · Overload Protection · Short Circuit Protection · Anti-Thump Turn-On PB-738GX High Performance 1000 Watt 2 Channel Bridgeable MOSFET Amplifier 2 · 100 Watts x 4 Output · Variable Input Level (Gain) Control · Remote Turn On/Off · Gold Plated RCA Inputs · High Level MOLEX Inputs · Power ON LED Indicator · S/N Ratio: > 95 dB · THD: <0.04% · Overload Protection · Short Circuit Protection · Anti-Thump Turn-On PB-238GX High Performance 400 Watt 4 Channel Amplifier general features

· 3000W x 1 Bridged Output · Variable Hi/Lo Electronic Crossover Network · Variable Bass Boost (0 - +18 dB @ 60Hz) · Variable Input Level (Gain) Control · Remote Turn On/Off · Gold Plated RCA Inputs · High Level MOLEX Inputs · Power ON LED Indicator · LED Protection Indicator · Remote Bass Boost · S/N Ratio: > 95 dB · THD: <0.04% · Thermal Protection · Overload Protection · Short Circuit Protection · Anti-Thump Turn-On PB-1836GX High Performance 3000 Watt 2 Channel Bridgeable MOSFET Amplifier general features · 1000 Watts x 4 Output · 2000 Watts x 2 Bridged Output(1000Wx2+2000Wx1) · Dual Variable Hi/Lo Electronic Crossover Network · Dual Variable Bass Boost (0 - +18 dB @ 60Hz) · Variable Input Level (Gain) Control · Remote Turn On/Off · Gold Plated RCA Inputs · High Level MOLEX Inputs · Power ON LED Indicator · LED Protection Indicator · Remote Bass Boost · S/N Ratio: > 95 dB · THD: <0.04% · Thermal Protection · Overload Protection · Short Circuit Protection · Anti-Thump Turn-On · Tri-Mode Configurable PB-1038GX High Performance 4000 Watt 4 Channel Bridgeable MOSFET Amplifier

speaker connections power terminals power fuse 4 ch amp PB-238GX high level inputs input level control low level inputs high level inputs input level control low level inputs power LED POWER LOW IN HI IN CH2 CH1 + - - + MIN MAX LEVEL CH 2 CH 1 LOW IN CH 4 CH 3 MIN MAX LEVEL HI IN CH4 CH3 + - - + 4 CHANNEL POWER AMPLIFIER + - - + - + - + CH3 CH4 GROUND +12V BATT REM FUSE CH1 CH2

low level inputs high level inputs power LED power fuse power terminals speaker connections use this control to match the outputs of your head unit to the amplifier. Starting with your head unit set at about the 2 o’clock position, increase the amp level control until distortion begins to occur, and reduce slightly from this point. this amp features gold-plated RCA input jacks for high impedance input. Use these with car stereo output which uses RCA-type connector cables. if your car stereo lacks RCA-type output jacks, you may connect speaker output leads to these input connectors. this indicator is illuminated when power is applied. the fuse protects the amplifier and your car’s electrical system from short circuit conditions. use these connectors to deliver power, ground and remote turn-on control to the amplifier. these terminals are 14K gold plated to guarantee high conductivity and minimum signal loss. frequency response power supply voltage output power @ 14.4v DC, 1KHz RMS Power @ 4 Ohms Maximum Power Output input sensitivity low level inputs high level inputs 30 Watts x 4 100 Watts x 4 15 Hz-30 KHz 250mV 2.5V 14.4V DC Neg. Ground (10.5-16V) maximum current draw dimensions (W x H x L) mm inches 2-4 Ohms 4-8 Ohms input impedance low level inputs high level inputs 10K Ohms 100 Ohms matching speaker impedance stereo mode bridged mode 10A 274 x 61 x 235 10.8 x 2.4 x 9.25 features and specifications 4 ch amp PB-238GX

crossover mode selector protection LED low pass frequency control bass boost level power LED high pass frequency control high level inputs input level control low level inputs speaker connections power terminals power fuse features and controls 2 ch amp PB-738GX • PB-1238GX LEVEL REMOTE BASS BOOST POWER PROTECT +18db 0 BASS BOOST 35 400 Hz LPF HPF 80 2.5k Hz FREQ. FULL HPFLPF L R HI IN R L + - - + LOW IN MIN MAX 2 CHANNEL MOSFET AMPLIFIER GROUND FUSE BRIDGED - + - + - + L R +12V BATT REM

output power @ 14.4v DC, 1KHz RMS Power @ 4 Ohms RMS Power @ 2 Ohms Maximum Power Output input sensitivity low level inputs high level inputs 75 Watts x 2 125 Watts x 2 500 Watts x 2 15 Hz-30 KHz 250mV 2.5V 14.4V DC Neg. Ground (10.5-16V) 150 Watts x 2 250 Watts x 2 1500 Watts x 2 maximum current draw dimensions (W x H x L) mm inches 2-4 Ohms 4-8 Ohms matching speaker impedance stereo mode bridged mode input impedance low level inputs high level inputs 10K Ohms 100 Ohms 20 A 40 A 274 x 61x 305 10.8 x 2.4 x 12 274 x 61 x 432 10.8 x 2.4 x 12 when used with normal, full range systems, set these switches to “FULL.” If you wish to use the internal crossovers to power a driver of specific frequency range, use the “LOWPASS” or “HIGHPASS” settings. use these controls to match the outputs of your head unit to the amplifier. Starting with your head unit set at about the 2 o’clock position, increase the amp level controls until distortion begins to occur, and reduce slightly from this point. when one or both of the crossover selector switches is in “low pass” mode, one can set the upper frequency limit for audio program sent to the speakers. when the one or both of crossover selector switch is in “high pass” mode, one can set the lower frequency limit for audio program sent to the speakers. this control permits adjustment of the bass level up to an increase of approximately 18 dB in either or both pairs of channels. this amp features gold-plated RCA input jacks for high impedance input. Use these with car stereo output which uses RCA-type connector cables. if your car stereo lacks RCA-type output jacks, you may connect speaker output leads to these input connectors. this indicator is illuminated when power is applied. this indicator is illuminated when built-in protection circuitry is activated. the fuse protects the amplifier and your car’s electrical system from short circuit conditions. use these connectors to deliver power, ground and remote turn-on control to the amplifier. these terminals are 14K gold plated to guarantee high conductivity and minimum signal loss. 7 PB-1838GX crossover mode selectors input level controls low pass frequency controls high pass frequency controls bass boost level controls low level inputs high level inputs power LED protection LED power fuse power terminals speaker connections Remote Bass Boost Plug in the Remote Bass Boost Control wire in here. features and specifications 2 ch amp PB-738GX • PB-1838GX

ch 3/4 high level inputs ch 1/2 low level inputs ch 1/2 high level inputs ch 3/4 bass boost level control ch 3/4 low pass frequency control ch 3/4 high pass frequency control ch 3/4 crossover mode selector switch ch 3/4 input level control ch 1/2 input level control ch 1/2 bass boost level control ch 1/2 low pass frequency control ch 1/2 high pass frequency control ch 1/2 crossover mode selector switch features and controls 4 ch amp PB-638GX • PB-1038GX 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4) BRIDGED + - - + - + - + CH3 CH4 GROUND +12V BATT REM BRIDGED FUSE - + - + CH1 CH2

output power @ 14.4v DC, 1KHz RMS Power @ 4 Ohms RMS Power @ 2 Ohms Maximum Power Output input sensitivity low level inputs high level inputs 35 Watts x 4 65 Watts x 4 400 Watts x 4 15 Hz-30 KHz 250mV 2.5V 14.4V DC Neg. Ground (10.5-16V) PB-1038GX 75 Watts x 4 125 Watts x 4 1000 Watts x 4 maximum current draw dimensions (W x H x L) mm inches 2-4 Ohms 4-8 Ohms matching speaker impedance stereo mode bridged mode input impedance low level inputs high level inputs 10K Ohms 100 Ohms 20 A 40 A 274 x 61 x 305 10.5 x 2.4 x 12 274 x 61 x 432 10.5 x 2.4 x 17 dual crossover mode selectors dual input level controls dual low pass frequency controls dual high pass frequency controls dual bass boost level controls low level inputs high level inputs power LED protection LED power fuse power terminals speaker connections when used with normal, full range systems, set these switches to “FULL.” If you wish to use the internal crossovers to power a driver of specific frequency range, use the “LOWPASS” or “HIGHPASS” settings. use these controls to match the outputs of your head unit to the amplifier. Starting with your head unit set at about the 2 o’clock position, increase the amp level controls until distortion begins to occur, and reduce slightly from this point. when one or both of the crossover selector switches is in “low pass” mode, one can set the upper frequency limit for audio program sent to the speakers. when the one or both of crossover selector switch is in “high pass” mode, one can set the lower frequency limit for audio program sent to the speakers. this control permits adjustment of the bass level up to an increase of approximately 18 dB in either or both pairs of channels. this amp features gold-plated RCA input jacks for high impedance input. Use these with car stereo output which uses RCA-type connector cables. if your car stereo lacks RCA-type output jacks, you may connect speaker output leads to these input connectors. this indicator is illuminated when power is applied. this indicator is illuminated when built-in protection circuitry is activated. the fuse protects the amplifier and your car’s electrical system from short circuit conditions. use these connectors to deliver power, ground and remote turn-on control to the amplifier. these terminals are 14K gold plated to guarantee high conductivity and minimum signal loss. CH 3/4 Remote Bass Boost Plug in the Remote Bass Boost Control wire in here. features and specifications 4 ch amp PB-638GX • PB-1038GX

+12V head unit 12V battery electrical connections 2 ch amp PB-738GX • PB-1838GX GROUND FUSE BRIDGED - + - + - + L R +12V BATT REM

+12V head unit 12V battery to remote turn-on +12V head unit 12V battery electrical connections 4 ch amp PB-238GX • PB-638GX • PB-1038GX BRIDGED + - - + - + - + CH3 CH4 GROUND +12V BATT REM BRIDGED FUSE - + - + CH1 CH2 BRIDGED + - - + - + - + CH3 CH4 GROUND +12V BATT REM BRIDGED FUSE - + - + CH1 CH2

PLEASE NOTE! If using high level inputs, do not use the low level RCA inputs at the same time! using high level inputs Y Adaptors L/R Audio Outputs from speaker terminals L L R R head unit stereo input connections 2 ch amp PB-738GX • PB-1838GX LEVEL REMOTE BASS BOOST POWER PROTECT +18db 0 BASS BOOST 35 400 Hz LPF HPF 80 2.5k Hz FREQ. FULL HPFLPF L R HI IN R L + - - + LOW IN MIN MAX 2 CHANNEL MOSFET AMPLIFIER LEVEL REMOTE BASS BOOST POWER PROTECT +18db 0 BASS BOOST 35 400 Hz LPF HPF 80 2.5k Hz FREQ. FULL HPFLPF L R HI IN R L + - - + LOW IN MIN MAX 2 CHANNEL MOSFET AMPLIFIER

PLEASE NOTE! If using high level inputs, do not use the low level RCA inputs at the same time! using high level inputs To a second amplifier Y Adaptors head unit wiring harness wiring harness To a second amplifier R R L L from speaker terminals 13 mono input connections 2 ch amp PB-738GX • PB-1838GX LEVEL REMOTE BASS BOOST POWER PROTECT +18db 0 BASS BOOST 35 400 Hz LPF HPF 80 2.5k Hz FREQ. FULL HPFLPF L R HI IN R L + - - + LOW IN MIN MAX 2 CHANNEL MOSFET AMPLIFIER LEVEL REMOTE BASS BOOST POWER PROTECT +18db 0 BASS BOOST 35 400 Hz LPF HPF 80 2.5k Hz FREQ. FULL HPFLPF L R HI IN R L + - - + LOW IN MIN MAX 2 CHANNEL MOSFET AMPLIFIER

2 CH input connections using low level inputs Y adaptors L R head unit L/R REAR Audio Outputs L/R FRONT Audio Outputs 14 2/4 channel input connections 4 ch amp PB-238GX POWER LOW IN HI IN CH2 CH1 + - - + MIN MAX LEVEL CH 2 CH 1 LOW IN CH 4 CH 3 MIN MAX LEVEL HI IN CH4 CH3 + - - + 4 CHANNEL POWER AMPLIFIER POWER LOW IN HI IN CH2 CH1 + - - + MIN MAX LEVEL CH 2 CH 1 LOW IN CH 4 CH 3 MIN MAX LEVEL HI IN CH4 CH3 + - - + 4 CHANNEL POWER AMPLIFIER

from speaker terminals L R FRONT L R REAR ORANGE ORANGE ORANGE ORANGE BLACK BLACK BLACK BLACK PLEASE NOTE! If using high level inputs, do not use the low level RCA inputs at the same time! CH 1/2 4 CH harness wiring for common ground connections from speaker terminals L R FRONT R L REAR ORANGE ORANGE ORANGE ORANGE BLACK BLACK BLACK BLACK CH 3/4 15 high level input connections 4 ch amp PB-238GX POWER LOW IN HI IN CH2 CH1 + - - + MIN MAX LEVEL CH 2 CH 1 LOW IN CH 4 CH 3 MIN MAX LEVEL HI IN CH4 CH3 + - - + 4 CHANNEL POWER AMPLIFIER

2 CH Stereo input connections using low level inputs Y adaptors R L head unit 16 L/R REAR Audio Outputs L/R FRONT Audio Outputs Stereo input connections 4 ch amp PB-638GX • PB-1038GX 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4) 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4)

17 from speaker terminals L R FRONT L R REAR ORANGE ORANGE ORANGE ORANGE BLACK BLACK BLACK BLACK PLEASE NOTE! If using high level inputs, do not use the low level RCA inputs at the same time! CH 1/2 4 CH harness wiring for common ground connections from speaker terminals L R FRONT R L REAR ORANGE ORANGE ORANGE ORANGE BLACK BLACK BLACK BLACK CH 3/4 high level Stereo input connections 4 ch amp PB-638GX • PB-1038GX 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4)

LEFT FRONT Audio Outputs 4 CH mono input connections using low level inputs 2 CH mono input connections using low level inputs Y adaptors L R head unit LEFT REAR Audio Outputs RIGHT REAR Audio Outputs 18 mono input connections 4 ch amp PB-638GX • PB-1038GX 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4) 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4)

4 CH harness wiring for common ground connections from speaker terminals PLEASE NOTE! If using high level inputs, do not use the low level RCA inputs at the same time! R L ORANGE ORANGE ORANGE ORANGE BLACK BLACK BLACK BLACK from speaker terminals CH 1/2 CH 3/4 R L ORANGE ORANGE ORANGE ORANGE BLACK BLACK BLACK BLACK 19 high level mono input connections 4 ch amp PB-638GX • PB-1038GX 4 CHANNEL MOSFET AMPLIFIER FREQ. CH 3 LOW IN LEVEL MIN MAX CH 4 HPF +18db 0 35 400 Hz LPF HPF 2.5k BASS BOOST MIN MAX FREQ. POWER PROTECT CH 1 CH 2 80 Hz LPF HI IN CH4 CH3 + - - + LOW IN BASS BOOST LEVEL FULL HPFLPF FULL HPF LPF CHANNEL 1/2 CHANNEL 3/4 HI IN CH2 CH1 + - - + +18db 0 2.5k 80 Hz 35 400 Hz REMOTE BASS BOOST(CH3/4)

speaker MINIMUM SPEAKER IMPEDANCE 4 OHMS! RIGHT speaker LEFT speaker 20 speaker connections 2 ch amp • PB-738GX • PB-1838GX GROUND FUSE BRIDGED - + - + - + L R +12V BATT REM GROUND FUSE BRIDGED - + - + - + L R +12V BATT REM

Bridged Dual Mono Output Mode (PB-238GX WITHOUT) MINIMUM SPEAKER IMPEDANCE 4 OHMS! speakers L R REAR speakers FRONT speakers L R R L speaker connections 4 ch amp PB-238GX • PB-638GX • PB-1038GX BRIDGED + - - + - + - + CH3 CH4 GROUND +12V BATT REM BRIDGED FUSE - + - + CH1 CH2 BRIDGED + - - + - + - + CH3 CH4 GROUND +12V BATT REM BRIDGED FUSE - + - + CH1 CH2

MINIMUM SPEAKER IMPEDANCE 4 OHMS! SPEAKERS R L SUBWOOFER 22 speaker connections 4 ch amp PB-638GX • PB-1038GX BRIDGED + - - + - + - + CH3 CH4 GROUND +12V BATT REM BRIDGED FUSE - + - + CH1 CH2

fuses wiring tips When making electrical connections to your amplifier, please observe the following: Use at least 8 gauge wire for power and ground connections. Wire the amplifier directly to the car battery. For the ground connection, use the shortest possible wire to a good chassis ground point. Wire the Remote connection to the auto start lead of your head unit, equalizer or power antenna. About power fuses: Pyramid Royal Blue Series amplifiers feature built-in fuse systems. These fuses protect both the amplifier and the electrical system in your vehicle from fault conditions. If you ever need to replace the fuse in your Pyramid Royal Blue Series amp, use a fuse of exactly the same type and rating. A different type or rating of fuse may result in damage or fire. mounting Your new Pyramid Royal Blue Series amplifier comes complete with all required mounting hardware. When determining a suitable location in your vehicle for the amp, please remember that it is a high-power electronic device capable of generating high heat. For this reason, always choose a location in your vehicle which has low vibration, adequate ventilation, a minimum of dust, and no moisture. Be sure to mount the amp in such a manner as to allow reasonable airflow over the cooling fins. Mark the location for the mounting screw holes by positioning the amp where you wish to install it and use a scribe (or one of the mounting screws) inserted in each of the mounting holes to mark the mounting surface. If the mounting surface is carpeted, measure the hole centers and mark with a felt tip pen. Before attempting to drill the mounting holes, take note of any wires, lines or other devices in your vehicle which may be located behind the mounting surface! Then drill pilot holes in the mounting surface for the mounting screws and insert them. Tighten the screws securely.

Royal Blue Series amplifiers will disable the amplifier if it senses an input overload, a speaker short circuit, or extreme temperature conditions. When the protection circuit is activated by any of these conditions, the Protection LED will be illuminated. If this occurs, carefully inspect the system to determine the source of the problem. • If the shutdown was a result of a thermal overload condition, allow the amplifier to cool down before attempting to restart it. • If the shutdown was a result of an input overload, or speaker short circuit, be sure to correct the condition before restarting. The amplifier can be restarted by turning the remote power OFF and then ON again. No output. Confirm that all terminal strip connections are secure and tight. Check both in-line and built-in fuses. Both the +12V and the Remote terminals must have +12v referenced to chassis ground. Confirm that the audio signal source (car radio, equalizer, etc.) is connected and is supplying output signal. To check if the amp is supplying signal, unplug the cables from the signal source (but leave them plugged into the amp). Briefly tap the center pin of each of the disconnected RCA plugs with your finger. This should produce a noise (feedback) in your speakers. Only one channel works. Confirm that all terminal strip connections are secure and tight. Check the Balance control on the head unit (or other source) to verify that it is set to its midpoint. If you are using the Low Level RCA input, reverse the input plugs at the amplifier (i.e., switch the L with the R). If the channels which is silent switches to the other side, the problem is either in the head unit/other source or the connecting cables. Weak output. Readjust the Input Level Control(s) to better suit the input signal. Noise in the audio. If the noise is a “whine” whose pitch follows the engine speed, confirm that the amplifier and any other signal sources (head unit, etc.) are properly grounded. If the noise is a “clicking” or “popping” noise whose rate follows the engine speed, this usually means that the vehicle is equipped with resistor spark plugs and wires, or that the ignition is in need of service. Check the rounting of the speaker and input wires to make sure they are not adjacent to wires which interconnect lights and other accessories. If the above steps fail to improve or clear noise interference, the system should be checked by a professional mobile audio installer. protection circuitry troubleshooting 24

Attach all audio system components securely within the automobile to prevent damage, especially in an accident. Do not mount this amplifier so that the wire connections are unprotected, or in a pinched condition, or likely to be damaged by nearby objects. Before making or breaking power connections in your system, disconnect the vehicle battery. Confirm that your head unit or other equipment is turned off while connecting the input jacks and speaker terminals. If you need to replace the power fuse, do so only with a fuse identical to that supplied with the amplifier. Using a fuse of a different type or rating may result in damage that isn’t covered in the manufacturer’s warranty. 25 precautions notes STOP YES! NO! 2 -c hannel Amplifier (Operating in Stereo) 4 ohm 4 ohm Two 4-ohm speakers, wired in stereo, will present a 4-ohm load to each channel of the amplifier. Most two- channel amplifiers will work well in this configuration. Two 4-ohm speakers, wired in parallel to a bridged two-channel amplifier. will present a 2-ohm mono load to the amplifier. MOST TWO-CHANNEL AMPLIFIERS DO NOT SUPPORT 2-OHM MONO OPERATION! AMPLIFIER DAMAGE COULD RESULT! sound around, Inc. 1600 63rd street. brooklyn. ny 11204 4 ohm 4 ohm 2 -c hannel Amplifier (Operating in Bridged Mono) STOP YES! NO! Four 4-ohm speakers, wired in stereo, will present a 4-ohm load to each channel of the amplifier. Most four- channel amplifiers will work well in this configuration. Four 4-ohm speakers, wired in parallel to a bridged four-channel amplifier, will present a 4-ohm mono load to the amplifier. MOST FOUR-CHANNEL AMPLIFIERS DO NOT SUPPORT 2-OHM MONO OPERATION! AMPLIFIER DAMAGE COULD RESULT! sound around, Inc. 1600 63rd street. brooklyn. ny 11204 4 -c hannel Amplifier (Operating in Bridged Mono) 4 ohm 4 ohm 4 ohm 4 ohm 4 -c hannel Amplifier (Operating in Stereo) 4 ohm 4 ohm 4 ohm 4 ohm