Introduction

The PowerBass Xtreme PowerSport Amplifier XL-900.5 is a high-performance audio amplifier designed for outdoor and automotive use, delivering an impressive 900 watts of power across five channels. Its Class D design ensures high efficiency and low current draw, making it ideal for various sound systems. Equipped with advanced features like variable electronic crossover and bass boost, it enhances audio clarity and depth. The amplifier is priced at approximately $299.99.

SPECIFICATIONS FOR XL MULTICHANNEL AMPLIFIERS

REQUIRES EXTERNAL FUSE !

Important Notes:

• Due to continuing improvements these specifications are subject to change without any notice.
• Do not attempt to fix or repair this unit. Unauthorized repairs will void the manufacturer’s warranty.

TECHNICAL FEATURES

• FRD (Full Range Class-D) Multi-Channel Technology
• International Rectifier Chip Set
• Conformal Coated PC Board to Resist Moisture, Dust and Extreme Heat
• AUX Input Accepts XL-BRT1, XL-BTRS, MP3, iPod® or Portable Source Device
• AUX Ouput (XL-250.2, XL-800.4)
• Wrap-around Aluminum Heatsink Shell
• Ultra Low Current Draw
• High Damping Control Circuit
• High Efficiency SMD Circuit Technology
• 4-Layer Copper Plated PCB
• Digital Sound Optimization Circuitry
• Quiet Switching
• Bass EQ Circuitry Centered at 45Hz (+/- 18dB)
• High Current Voltage Ripple Rejection Circuitry
• Virtual Silence Turn On/Off Mute Circuit
• Advanced Protection Circuitry
• Low Level RCA and High Level Speaker Inputs
• Wired Remote Level Control (XL-250.2 & XL-900.5)

*iPod is a registered trademark of Apple

FRD-FULL RANGE CLASS D TECHNOLOGY

• This amplifier represents the very latest in Class D technology. The XL Series uses the new IR® (International Rectifier) platform which has been under development for the past several years. IR®, a leader in PWM circuit design, has worked in conjunction with PowerBass engineers to produce more stable power output, minimal RF interference and improved sound quality.
• The benefits of this cooperative effort are many and include improved temperature, frequency, voltage regulation and drive capability to name a few.
• The PC board features a conformal coating that resists moisture, dust and extreme heat. Combine that plus their small size and these amplifiers are perfect for many Powersport applications including UTV, golf cart and motorcycle and Watersport vessels.
• The result to the user is a all around improved product that will provide years of listening enjoyment.

INSTALLATION EXPERIENCE

Installation of PowerBass mobile amplifiers requires detailed knowledge of electronics wiring and proper speaker impedance. We strongly recommend installation by an authorized PowerBass dealer. This Owners Manual only provides general installation and operation instructions. If you have any reservations about your installation skills, please contact your local PowerBass dealer for assistance.

IMPORTANT : This amplifier is designed for operation in vehicles with 12-volt Negative ground electrical systems only.

PREPARING FOR INSTALLATION

NOTE: The tools listed below may be required for basic installation

• An electric drill with bits
• Philips head and standard screwdrivers
• Wire strippers
• Crimping tool
• VOM (electronic volt ohm meter)
• Heat shrink tubing and heat gun
• Soldering iron
• Electronic (Rosen not Acid Core) Solder

INSTALLATION PRECAUTIONS

NOTE: Proceed only if you are a qualified installer, otherwise; see your Authorized PowerBass Dealer to professionally install this amplifier. Always wear protective eyewear when using tools.

• Turn off all stereo and other electrical devices before you begin.
• Disconnect the negative (-) lead from your vehicles battery.
• Locate all fuel lines, brake lines, oil lines, and electrical cables when planning the install.
• Make sure there is at least 2-inches (5 cm) around the air vents on the amplifier.
• When connecting ground points, make sure all paint is carefully scrapped away from the auto body and contact is made with bare metal.
• Use a utility knife to trim away fabric from hole locations before drilling or cutting.
• When running power cables through sheet metal, be sure to use grommets to properly insulate the metal edges from the wire insulation.
• If possible, use tubing through grommets.

WARNING: Check your vehicle’s owner’s manual before disconnecting the battery. Disconnecting the battery on some vehicles may require an anti-theft code when reconnecting the battery and require the on-board computer to be reset at the dealership. Check with your local dealer if you are uncertain.

MOUNTING THE AMPLIFIER

To keep your PowerBass Xtreme amplifier running at top performance, choosing the proper location is of utmost importance. Both Thermal and Overload protection are built in. In the event of overheating, the amplifier will turn off and only restart when cooled. For this reason the amplifier should be mounted in a location which will allow air to circulate freely. The compact size of the PowerBass XL Series amplifier allows greater flexibility in mounting.

CAUTION: Not water or mud proof. Cannot be submerged or it will void the warranty!

MOUNTING LOCATION

• The XL Series amplifiers have a conformal coating applied to the PC board. This coating makes them resistant to water and dust—however they are not waterproof. Therefore, care should still be taken to protect the am-plifier from water and find a mounting location that is not likely to get wet. Take care not to mount in a vehicle/vessel where it can cause interference with the factory installed electronic devices.
• The unique wrap around outer shell (heatsink) allows the XL Series amplifiers to be mounted in spaces with minimal air flow. It is important that whatever location is selected the amplifier must be mounted securely in a manner keeps the unit intact even during rough jolts that can occur to the vehicle/vessel.
• You may use the amplifier as a template and mark the four screw locations with a felt tip pen. Set the amplifier aside before drilling. Use caution to make sure there are no objects behind the installation surface that may become damaged during drilling.
• If mounting under a seat, make sure there is at least 1-inch (2.5 cm) of space above the amplifier’s heatsink to permit proper cooling.
• The best places to mount your amplifier are: The floor of the trunk, under a seat, on the back of the rear seat or a storage compartment will air can circulate. For alternate installation locations, please consult your authorized PowerBass Dealer.

NOTE: Do not use a drill with driver bit to mount the amplifier. Excessive force could cause the plastic mounting feet to crack.

WARNING 

• Do not install in a place where it could injure the driver or passengers if the vehicle stops suddenly.
• Try to avoid mounting the amplifier on a subwoofer enclosure, as extended exposure to vibration may cause malfunction of the amplifier.
• Don’t mount the amplifier so that the wire connections are unprotected or are sub-ject to pinching or damage from nearby objects.
• The DC power wire must be fused at the battery positive (+) terminal connection. Before making or breaking power connections at the amplifier power terminals, disconnect the DC power wire at the battery end.
• The battery of the car audio system must be disconnected until the entire wiring and installation is completed.

XL-900.5 CONTROL PANEL LAYOUT

NOTE: Panel Layout and Controls may differ by model.

1. REAR Low Level RCA and High Level Speaker Inputs
   Use this Low Level 4-pin High/Low style input is where the wiring harness plugs in for the Low Level input that connects to source units with RCA line level outputs. A source unit with a minimum input of 250mV is required for proper operation. However, this input can accept levels up to 10Vrms.
2. SUBWOOFER INPUT Connector
   This is both a Low and High Level Input port. Using the supplied wiring harness for low level RCA inputs or cut the plug as instructed on Fig.9 for High Level (speaker level) input.
3. POWER/STATUS Indicator
   This clear LED lights Blue when the power is on—or turns Red constantly when the built-in protection circuitry is activated. Red indicates a problem with the system in relation to the amplifier (See Troubleshooting Tips).
4. REAR GAIN Control
   This control is used to match the input sensitivity of the amplifier to the particular source unit that you are using up to 250mV to 10 volts.
5. SUBWOOFER BASS EQ Control
   This equalization circuit is used to enhance the low frequency response of the vehicle’s interior. With up to 18dB of boost centered at 45Hz, the BASS EQ can be adjusted to meet your own personal taste.
6. REAR HPF
   This control is continuously adjustable from 40Hz to 400Hz at 12dB per octave when the x-over switch is set to HPF.
7. SUBWOOFER LPF (Low Pass Filter)
   This control is continuously adjustable from 50Hz to 150Hz at 12dB per octave.
8. FRONT HPF
   This control is continuously adjustable from 40Hz to 400Hz at 12dB per octave).
9. SUBWOOFER GAIN Control
   This control is used to match the input sensitivity of the amplifier to the particular source unit that you are using up to 250mV to 10 volts.
10. MODE Switch
    Matches the input from the Source Unit to that of the amplifier, either 2 or 5 Channel. This eliminates the use of “Y” adapters and provides a cleaner input signal. When the 2-Channel mode is selected, both Front, Rear and Sub outputs will operate with only one pair of low level RCA inputs. In 2CH mode, use Front inputs only.
11. REMOTE LEVEL INPUT Connector 
    This is the connector port for the Remote Level Controller. Now the amplifiers secondary gain circuit for the subwoofer output can be adjusted from the driver’s seat.
12. FRONT GAIN Control
    This control is used to match the input sensitivity of the amplifier to the particular source unit that you are using up to 250mV to 10 volts.
13. FRONT Low Level RCA and High Level Speaker Inputs
    Use this Low Level 4-pin High/Low style input is where the wiring harness plugs in for the Low Level input that connects to source units with RCA line level outputs. A source unit with a minimum input of 250mV is required for proper operation. However, this input can accept levels up to 10Vrms.
14. AUX Input Jack
    This 1/8-inch (3.5mm) mini jack can be used to accept an MP3, iPOD or smartphone as the source unit from that devices headphone (3.5mm) output. When using AUX input, the amplifier must be in 2CH mode.
15. SUBWOOFER OUTPUT
    Set screw subwoofer output terminal. Be sure to observe the correct speaker polarity and follow the speaker wiring diagrams starting on page 25.
16. FRONT SPEAKER OUTPUT 
17. REAR SPEAKER OUTPUT
    This 4-pin Molex style connector is where the speaker output harness plugs in. Be sure to observe the correct speaker polarity and follow the speaker wiring diagrams found elsewhere in this owners manual.
18. BATT+ (Power Input Connection)
    This terminal is the main power input for the amplifier and must be connected directly to the positive (+) terminal of the car battery. The solderless terminal block is designed to accommodate up to 8-gauge power wire.
    FUSE-IMPORTANT
    Due to the limited space on the XL amplifier chassis they do NOT come with internal fusing! Instead we have included an in-line fuse holder that can be connected directly to the BATT+ input on the amplifier. Please note the proper ampere fuse for each model are listed below. Never replace a fuse with a higher rating then what is listed. (XL-250.2 uses 40A, XL-800.4 uses 60A, XL-900.5 uses 80A)
19. REM (Remote Input Connection)
    This terminal must be connected to a switched +12V source. Typically, remote turn-on leads are provided at the source unit that will turn on and off the amplifier in correspondence with the source. If this lead is not at the source unit, then a switched +12V supply must be used, like the ACC, +12V.
20. GND (Ground Input Connection)
    A good quality ground is required for your PowerBass Xtreme amplifier to operate at peak performance. A short length of cable the same gauge as your power cable should be used to attach the ground terminal directly to the chassis of the vehicle. Make sure that all of the paint is sanded or scraped away to ensure a quality ground connection. 
    NOTE: If installing in a boat, UTV or motorcycle make sure your ground wire is connected to the negative ( - ) terminal of the battery.

Description

The PowerBass Xtreme PowerSport Amplifier XL-900.5 is engineered to deliver exceptional sound quality and reliability in demanding environments. Its 5-channel design allows for versatile configuration, supporting both full-range speakers and a dedicated subwoofer channel. The amplifier features a robust MOSFET power supply and an aluminum heat sink to ensure efficient cooling and long-term reliability.

The waterproof and corrosion-resistant design makes it perfect for marine and powersport applications, where exposure to moisture and salt is common. The variable crossover controls enable users to fine-tune their audio setup, ensuring optimal performance from their speakers and subwoofers.

POWER WIRING AND SIGNAL CONNECTIONS

WARNING 
Disconnect the negative (-) battery terminal before you start any wiring work! The battery of your car audio system must be disconnected until the entire wiring installation is completed.

Your PowerBass Xtreme amplifier requires unrestricted current to deliver peak performance, so do not “starve” your amplifier by using small power cable. Using under sized power cable can result in unnecessary over-heating of the amplifier, distortion at high volume levels and might even cause the thermal protection circuitry to shut-off the amplifier. Remember, bigger wire is better! For best results we recommend a PowerBass ampli-fier install kit, available at your local PowerBass dealer.

• Use rubber grommets when running cables through any metal or sharp plastic, to prevent accidental shorting or shearing. Make sure the cables do not interfere with normal operation of the vehicle.
• The audio signal cables (RCA interconnects) should be kept far away from any potential sources of electrical interference such as electronic vehicle management systems (relays, engine computers etc.), wiring harnesses, fuel pumps etc.

These amplifiers are designed to work within a 10 to 16 volt DC range. Before any wires are connected, the vehicles electrical system should be checked for correct voltage supply with the help of a voltmeter.

First, check the voltage at the battery with the ignition in the OFF position. The voltmeter should read no less than 12V. If your vehicles electrical system is not up to these specifications, we recommend having it checked by an auto electrician before any further installation. Once the vehicle is checked, make certain the correct cable gauge is used. The XL amplifier terminals are capable of accepting up to 4 gauge power and ground cable. We recommend using as large a gauge cable as possible, use the Power Cable Selection Chart to cal-culate the correct power wire size for your application.

POWER WIRING

BATT+ (Power)

This amplifier should be wired directly to the vehicle battery using the appropriate size cable. Start at the vehicle battery and run the power cable through to the amplifier. Avoid running the power cable over engine components and near heater cores. The use of an inline fuse or circuit breaker is a must; this will prevent the risk of a potential fire caused by a short in your power cable. Connect the fuse holder or circuit breaker as close to the battery positive (+) terminal as possible (within 18” from the battery). You may now connect the cable to the battery, but remember to leave the fuse out or circuit breaker “off” until all other cable connections are made.

GND (Ground)

When grounding your amplifier, locate a metal area close to the amplifier that is good source of ground (preferable the floor pan). Use a short length of cable the same gauge as your power cable. Once again, investigate the area you wish to use for electrical wires, vacuum lines, and brake or fuel lines. Use either a wire brush or sandpaper to eliminate unwanted paint for better contact of the ground. 

: If installing in a boat, UTV or motorcycle make sure your ground wire is connected to the negative ( - ) terminal of the battery. See Fig. 7

Secure the ground cable to the body using a bolt, star washer and nut. Spread silicon over the screw and bare metal to prevent rust and possible water leaks.

For Power Sport applications such as UTVs, motorcycles and boats it is highly recommended to wire both the Ground (GND) and Positive (BATT+) cables from the amplifier directly to the battery.

NOTE: The Ground must be capable of carrying the same amount of current as the positive wire.

Now it’s time to connect the power and ground cables to the amplifier. Cut both cables to length. Strip off 1/2 inch (12mm) of the insulation so that the bare wire fits all the way in the terminal block on the side panel of the amplifier, seating it firmly so no bare wire is exposed. Use a screw driver to losen the BATT+ and the GND connection on the amplifier. Insert the ground first, and then the +12V and please make sure that you place them into the correctly marked terminals. Hand thighten the set screws and make sure the connection is secure to prevent possible arcing due to loose screws.

REM (Remote Trigger)

This terminal must be connected to a switched +12V source. Typically, remote turn-on leads are provided at the source unit that will turn on and off the amplifier in correspondence with the source. If the source unit does not have a remote turn-on lead, then a switched +12V supply must be used, like the ACC, +12V.

Run a minimum of 18 gauge wire from the amplifier location to the source of the switched +12V lead. If possible, route this wire on the same side of the vehicle as your power cable. Connect the source remote output to the wire. Go back to the amplifier and cut the wire to length. Loosen the screw terminal marked REM on the amplifier using an Allen wrench. Insert the stripped (bare) portion of the wire into the terminal and tighten the screw securely.

CONNECTIONS TO AMPLIFIER FOR BATT+, GND, REM AND SPEAKERS
Your PowerBass Xtreme amplifier features specially tooled solderless terminals for Power (BATT+), Ground, Remote, and Speaker connections. For maximum transfer of Voltage and Signal the bare wire needs to be inserted as far as possible into the terminal before tightening the set screw. For Power (BATT+) and Ground connections it is highly recommended that the bare ends of the wires are tinned with solder before inserting them into the terminal. Hand tighten the set screw and make sure the connection is secure to prevent possible arcing due to loose screws.

NOTE: It is highly recommended that an Allen wrench is used to tighten the set screws in the terminal blocks by hand and NOT a power drill. This will prevent stripping or other possible damage to the amplifier.

FUSE REQUIREMENTS

Due to the small size of the PowerBass XL series amplifiers, no fuses are incorporated into the panels that normally protect the unit from excessive current. Instead we have included an in-line fuse holder and fuse for this purpose.

• XL-250.2 40A
• XL-800.4 60A
• XL-900.5 80A

It is vital that the main power lead to the amplifier(s) in the system be fused within 18-inches (45cm) of the connection to the battery. The value of this fuse (or circuit breaker) should be no greater than the fuse rating above.

Proper Ground Connection For UTVs, Motorcycles or Boats

SOURCE INTERCONNECT

• Choose the correct length and style of RCA interconnects for your needs. Always use high quality RCA audio cables (not supplied) for signal connections—those with multiple layers of shielding or a twisted pair variety for better noise rejection.
• Be extra careful when routing your RCA audio interconnect cables. Car environments are notorious for poorly insulated wires. This means that hiss, engine noise, and fan noise can easily be picked up through RCA cables if run incorrectly.
• Make sure that the cables for power and audio signal are not on the same side of the vehicle and that they do not cross each other; this will help reduce any noise that may radiate from the power cable and the signal cable. If an audio cable is too close to a power cable, it may pick up the magnetic field generated by the power cable, which could lead to a loss of quality in your signal.

NOTE: A side panel AUX Input is available for use with portable MP3 players or an iPod * Use of this input will override (defeat) the RCA low level inputs.

1. Cut RCA Plugs off at the black heatshrink in the middle of the pigtail wires.
2. Connect the wires from the speaker output of the radio to the white and grey wires of the amplifier input wires using the color codes in above drawing.

AUX INPUT WIRING

Typical 2 amplifier setup

MP3 or Portable Device as a Source

The XL Powersport Series amplifiers all feature a AUX source input. This allows you to substitute a portable music device such as an iPOD, Smartphone, MP3 Player, etc instead of a traditional radio as your music source. Above is a typical two amplifier system—a multi-channel amplifier (our 2-channel XL-250.2 or our 4-channel XL-800.4) to power the full range speakers and a mono bass amplifier (our mono XL-400.1D or XL-600.1D) to power the subwoofer(s).

You will need to use a quality shielded 1/8-inch (3.5mm) stereo male to male audio cable for this type of set up. Route the shielded audio cable using the same care as you would with the RCA interconnect for a traditional source unit.

NOTE: A side panel AUX Input is available for use with XL-BTR1, XL-BTRS, & portable MP3 play-ers or an iPod ®* Use of this input will override (defeat) the RCA low level inputs.

SET UP ADJUSTMENTS

INPUT Gain Adjustment

This control allows you to match the input level of the amplifier to the output level of your head unit. Matching the input can be accomplished in three simple steps:

1. Set the volume of GAIN on the amplifier to Min (completely counter clock wise).
2. Turn on the head unit and adjust volume to 2/3 maximum, and set the BASS and TREBLE to zero.
3. Adjust the GAIN control clockwise until the sound just begins to distort, then back off slightly to cut distortion and operate at optimum gain.

Remember, the GAIN control is not a volume control. Ignoring the three steps above may leave you with damaged speaker and/or a damaged amplifier.

BASS EQ Control
This special feature is designed to provide you more powerful sound quality, and it allows you to increase the bass output up to +18dB at 45Hz (Rear Channel only). Keep in mind more is not always better. Setting the control to the max (18dB) may stress the amplifier and woofer and could result in damage. Bass EQ only works in Low Pass Mode (Rear Channel only on XL-4165M). NOTE: More is not always better. By turning the BASS EQ all the way up to 18dB you can overwork the amplifier and send the unit into thermal protection.

LPF (Low Pass Filter) Adjustment
Using this volume, adjust the LPF frequency for your subwoofer speaker(s) operation. Using the LPF control, adjust the Low Pass Frequency to limit the amount of midrange going to your speakers. The X-OVER switch position should be at “LPF”.

HPF (High Pass Filter) Adjustment
When you are using coaxial or component speaker system, this allows you to adjust high-pass X-over frequency from 40Hz to 400Hz. To get better sound quality from coaxial or component speaker system, we recommend the frequency should be higher than 80Hz. Make sure the X-OVER switch is positioned at “HPF”. NOTE: The HPF circuit is always active on the front channels of the XL-800.4.

SPECIAL CONTROLS FOR THE XL-900.5

The following instructions apply to the model XL-900.5 only. You will not find these controls on the other models in this series.

MODE Switch 
Matches the input from the Source Unit to that of the amplifier, either 2 or 5 Channel. This eliminates the use of “Y” adapters and provides a cleaner input signal.

• When the 2-Channel mode is selected, front, rear, and sub outputs will operate with only one pair of low level RCA inputs. Using only the front inputs.
• When the 5-Channel mode is selected, all inputs must be used Front, Rear,and Subwoofer. This will allow for fade and control between Front and Rear / Subwoofer outputs.

AUX INPUT NOTE: The MODE switch must be in the 2-Channel position in order to use the 3.5mm AUX input

REMOTE LEVEL Controller Connection (XL-250.2 & XL-900.5)

Your PowerBass Xtreme amp includes a Remote Level control module. To connect the Remote Level Control to the amplifier, simply insert one end into the REMOTE LEVEL port. Plug the other end into the remote module. Install the module within easy reach on or under your dash.

NOTE: XL-250.2 the remote level works in all settings HP,LP, FULL and channels / XL-900.5 the remote level works only with the Subwoofer output.

Speaker Load
Keep in mind your PowerBass Xtreme amplifier is a high power amplifier and not a high current amplifier. In other words The amplifier's minimum impedance is 2 ohms STEREO and 4 ohms bridged to operate trouble free. Lower impedance will send the amplifier into protection and possibly damage the electronics inside and void the waranty.

NOTE: Know your total impedance load before you make any connections.

Speaker Wiring
Choose the correct speaker wire for your application. Most applications will require a minimum of 16 gauge wire. At the amplifier end, splice the speaker wires to the properly marked output leads from the Molex style connector. Route these using the same precautions as you did when you ran the power cable. Check to make sure you’ve maintained proper polarity and balance.

CAUTION:
Maintaining proper impedance is critical when wiring the Full Range Digital model amplifiers. Improper wiring can cause severe damage to BOTH the speakers and the amplifier. Detailed wiring diagrams are supplied with all PowerBass woofers.

IF YOU ARE NOT EXPERIENCED OR UNCOMFORTABLE READING THE WIRING DIAGRAMS CONSULT YOUR AUTHORIZED POWERBASS DEALER BEFORE YOU ATTEMPT TO WIRE THE SYSTEM.

Speaker Output Connections 5 Channel Model (XL-900.5)

3. 5-Channel Speaker Output Connection

4. 2-Channel Stereo/Mono Speaker Output Connection

RECOMMENDED WIRE SIZES

PowerBass makes several types of amplifier wiring kits to assist with the installation of your PowerBass amplifier. Consult your local PowerBass dealer for details. For more information about recommended power wire check out our website at https://www.powerbassusa.com 

Troubleshooting

NOTE: After using all the troubleshooting tips above, if the Status L.E.D. is activated and glows RED with no speak-ers connected to the amplifier, and all the power connections are correct, this would indicate an internal problem with the amplifier. Contact PowerBass USA or your local dealer.

Pros & Cons

Pros

• High-Performance Output: Delivers powerful sound with clear highs and deep bass.
• Durable Design: Waterproof and corrosion-resistant, making it ideal for marine and powersport use.
• Flexible Configuration: 5-channel design allows for multiple speaker and subwoofer configurations.
• Efficient Cooling: Aluminum heat sink ensures reliable operation even in harsh environments.
• User-Friendly Controls: Variable crossover controls make it easy to fine-tune your audio setup.

Cons

• Size: The amplifier is relatively large and may require careful placement in smaller vehicles.
• Cost: While competitive, it is still a significant investment for some users.
• Complex Installation: Requires careful wiring and setup, which can be challenging for DIY enthusiasts without experience.

Customer Reviews

Customers have praised the PowerBass Xtreme PowerSport Amplifier XL-900.5 for its exceptional sound quality and robust build. Many have noted its ability to withstand harsh marine environments without compromising performance. However, some users have mentioned that the setup process can be complex and time-consuming.

Common complaint is the size of the amplifier, which can be a challenge in smaller vehicles. Despite this, most users agree that the benefits outweigh the drawbacks, making it a top choice for those seeking high-performance audio in demanding conditions.

WARRANTY

PowerBass Xtreme Amplifiers are to be free of defects in material and workmanship for a period of one (1) year.