ESX QXB8A

The ESX QUANTUM QXB8A is a powerful active subwoofer system that delivers impressive bass performance despite its compact size. The bass-reflex enclosure combines a high-quality 20 cm (8-inch) subwoofer with an integrated Class D amplifier module that delivers up to 400 watts RMS and 800 watts of peak power.

Unlike many conventional active subwoofers, the ESX features the powerful POWER4 amplifier module with state-of-the-art Class D technology. With an efficiency of up to 84%, the power amplifier operates particularly efficiently and delivers high bass levels despite its compact design.

Thanks to its built-in EPS® PRO technology, the QXB8A is also suitable for integration into modern vehicles equipped with factory-installed sound systems. In addition to RCA inputs, high-level inputs with an automatic power-on function are available. The input sensitivity can be switched between 15 and 40 volts.

For custom sound tuning, the active subwoofer features an adjustable low-pass filter, a bass boost, and a phase switch. The three-stage limiter function and a clipping indicator help you monitor the amplifier. Using the included wired remote control, the bass level can be conveniently adjusted from the driver’s seat.

Another unique feature is its flexible installation options. Using the four mounting feet included, the enclosure can also be used in down-firing mode, so that the subwoofer radiates sound downward. This makes the system ideal for installation in double trunk floors, for example.

The sturdy, compact enclosure, featuring an embroidered ESX logo and a robust protective grille, gives the subwoofer a high-quality look and protects it during everyday use.

Technical Specifications

General Characteristics

• Manufacturer: ESX

• Model: QXB8A

• Series: QUANTUM QXB

• Product Type: Active Subwoofer System

• Design: Bass-reflex enclosure

• Subwoofer diameter: 20 cm (8 inches)

• Integrated Amplifier: POWER4 Active Module for 10 mm² Power Input

• Amplifier Technology: Class D

• Efficiency of the amplifier module: Up to 84%
  
  

Performance Data

• RMS output power: 1 × 400 watts

• Maximum output power: 1 × 800 watts
  
  

Filters and Sound Settings

• Low-pass filter (LPF): 40–120 Hz, continuously adjustable

• Low-pass slope: 12 dB/octave

• Bass Boost: 0–6 dB

• Bass boost center frequency: 45 Hz

• Phase switch: 0° / 180°

• Subsonic filter: Specified in an independent test as 5–35 Hz at 12 dB/octave
  
  

Connections and Input Signals

• Low-level RCA input: Available

• High-level input: Available

• Automatic power-on function: via DC detection or audio signal

• High-level input sensitivity: 15 V / 40 V, switchable

• EPS® PRO Technology: Integrated

• EPS® PRO Resistance Settings: 10 Ω / 150 Ω / 600 Ω, switchable

• Start-stop capability: Yes

• Voltage stability during start-stop: Up to 7 volts for 5 seconds
  
  

Protection and Control Functions

• Three-stage limiter function: Available

• Clipping Indicator: LED

• Bass Level Remote Control: Wired

• Remote bass level control: Available
  
  

Housing and Dimensions

• Enclosure Type: Compact bass-reflex enclosure

• Enclosure width: 480 mm

• Enclosure height: 330 mm

• Enclosure depth: 180 mm

• Case surface: Features an embroidered ESX logo

• Subwoofer grille: Included

• Downfire mode: Possible

• Mounting feet: 4 pieces for down-firing installation
  
  

What's Included

• 1 × ESX QUANTUM QXB8A Active Subwoofer System

• 1 × Wired Bass Level Remote Control

• 4 × mounting feet for down-firing operation

• Safety Gate