ESX QL800.4 4-Channel Class D Amplifier

The ESX QL800.4 is a QUANTUM QL 4-channel Class D digital amplifier for compact car audio installations. The official ESX page and owner manual confirm 4 x 125W RMS at 4 ohm, 4 x 200W RMS at 2 ohm and 2 x 400W RMS bridged at 4 ohm.

It includes high-level inputs with EPS, auto turn-on, Start/Stop readiness, a MOSFET PWM power supply, 3-way protection, 2/4-channel input selection, copy mode for CH3/4 to CH1/2, bandpass-capable filtering and a compact bass remote controller.

Key specifications

• 4-channel Class D digital amplifier
• 4 x 125/200W RMS at 4/2 ohm
• 2 x 400W RMS at 4 ohm bridged
• High-level inputs with Error Protection System (EPS)
• HPF 50-5000 Hz on CH1/2
• HPF 10-500 Hz and LPF 50-5000 Hz on CH3/4
• Copy mode CH3/4 > CH1/2, bass boost 0-12 dB and bandpass function
• Dimensions 226 x 43 x 120 mm

Best used for

Use the QL800.4 for a compact 4-channel speaker amplifier, a bridged two-channel setup, or a front-stage plus subwoofer system where a space-saving amplifier and remote bass control are useful.

Setup note

System design and channel assignment matter on bridgeable multi-channel amplifiers. If you are unsure how to wire this into your vehicle, send us your system details by WhatsApp or email before ordering and we will help check the setup.