QX300A

High Performance 2 x 150W Power Amplifier

The Quest QX300A is a high-performance 2 x 150W power amplifier engineered for versatile installation applications. Utilizing advanced UMAC™ Class-D technology, it offers exceptional efficiency and intelligent auto load sensing for both Low-Z and High-Z configurations. Its compact design supports wall or table mounting and high-density installation with up to 10 units per 3RU rack space. Robust construction—including a diecast base and comprehensive protection circuits—ensures reliable operation in demanding environments, making the QX300 a dependable solution for professional audio systems.

Key Specifications:

Channels: 2 x 150W (Low-Z) or 1 x 300W (Bridge Mono for Low-Z & 70/100V)
Mounting: Wall/Table
Rack Density: 3 units per 1RU

SPECIFICATIONS

POWER (PEAK)

Total Power 550 W

Normal Operation

8Ω 2 x 200W

4Ω 2 x 275W

70V N/A

100V N/A

Bridge-Mono Mode

8Ω 1 x 550W

4Ω 1 x 550W

70V 1 x 550W

100V 1 x 550W

POWER (RMS)

Total Power 300 W

Normal Operation

8Ω 2 x 150W

4Ω 2 x 140W

70V N/A

100V N/A

Bridge-Mono Mode

8Ω 1 x 280W

4Ω 1 x 260W

70V 1 x 250W

100V 1 x 240W

I/O

OUTPUT CIRCUITRY UMAC™ Class-D – full bandwidth PWM modulator with ultra-low distortion

OUTPUT CHANNELS Two Speaker Level Output via 2-pin Euroblock/Phoenix connector with 5.08 mm pitch and screw-lock

INPUT CHANNELS Two Analogue Balanced Line Level Inputs via 3-pin Euroblock/Phoenix connector with 5.08 mm pitch and screw-lock

DEFAULT GAIN 32 dB

FREQUENCY RESPONSE 20 Hz to 20 kHz (+/-0.3 dB)

TOTAL HARMONIC DISTORTION 0.003% (1 kHz @ 1/8th Power / 8 ohm load)

DYNAMIC RANGE 112 dB (A-weighted)

MAXIMUM INPUT LEVEL +24 dBu

INPUT IMPEDANCE 10kohm

LATENCY N/A

CONTROL

CONTROLS AND INDICATORS (FRONT) Per Channel: Volume Potentiometer.Per Unit (Applies to both channels): 80 Hz HPF Switch, 100 Hz LPF Switch, Bridge-Mono Switch, Limiter Switch and Auto-Standby Switch

CONTROLS AND INDICATORS (REAR) N/A

CONTROL AND MONITORING N/A

DIGITAL SIGNAL PROCESSING N/A

PROTECTION CIRCUITS Thermal protection, Over-Current Protection, DC Protection, HF Protection

ELECTRICAL

MAINS POWER INPUT Universal Mains, 100-240V, 50-60 Hz

MAINS CONNECTOR Standard IEC C14

POWER CONSUMPTION - STANDBY 0.4 W

POWER CONSUMPTION - IDLE 7.2 W

POWER CONSUMPTION - 1/8TH POWER / 8 ohm Load 38 W

POWER CONSUMPTION - 1/3RD POWER / 8 ohm Load 100 W

HEAT

HEAT GENERATED - STANDBY 1.4 BTU/hr / 0.3 kJ per hour

HEAT GENERATED - 1/8TH POWER / 8 ohm Load 43 BTU/hr / 11 kJ per hour

COOLING Fan-Forced Air Cooling – Temperature-Dependent

FAN NOISE (ANECHOIC CHAMBER @ 1 m) 38 dB(A)

SIZE

RACK SIZE 1RU High and 1/3-Rack Width

DIMENSIONS (W x H x D) 125 x 44.5 x 330 mm (5.5 x 1.75 x 13")

WEIGHT 1.6 kg (3.5 lbs)

SHIPPING DIMENSIONS (W x H x D) 250 x 80 x 420 mm (9.8" x 3.15" x 16.5")

SHIPPING WEIGHT 3 kg (6.6 lbs)

ACCESSORIES

ACCESSORIES (INCLUDED) Mains Cable, Feet, Euroblock/Phoenix Plugs, Rack Ears

ACCESSORIES (AVAILABLE SEPARATELY) uRAK2 and WBQX300

OPTIONS Dante Version Available - QX300D

Maximum Dynamic Power (@ 1kHz, 1% THD) (PEAK)

Total 550 W	Normal Operation				Bridge-Mono Mode
Total 550 W	8Ω 2 x 200W	4Ω 2 x 275W	70V N/A	100V N/A	8Ω 1 x 550W	4Ω 1 x 550W	70V 1 x 550W	100V 1 x 550W

Maximum Continuous Power (@ 1kHz, 1% THD) (RMS)

Total 300 W	Normal Operation				Bridge-Mono Mode
Total 300 W	8Ω 2 x 150W	4Ω 2 x 140W	70V N/A	100V N/A	8Ω 1 x 280W	4Ω 1 x 260W	70V 1 x 250W	100V 1 x 240W

I/O

OUTPUT CIRCUITRY	UMAC™ Class-D – full bandwidth PWM modulator with ultra-low distortion
OUTPUT CHANNELS	Two Speaker Level Output via 2-pin Euroblock/Phoenix connector with 5.08 mm pitch and screw-lock
INPUT CHANNELS	Two Analogue Balanced Line Level Inputs via 3-pin Euroblock/Phoenix connector with 5.08 mm pitch and screw-lock
DEFAULT GAIN	32 dB
FREQUENCY RESPONSE	20 Hz to 20 kHz (+/-0.3 dB)
TOTAL HARMONIC DISTORTION	0.003% (1 kHz @ 1/8th Power / 8 ohm load)
DYNAMIC RANGE	112 dB (A-weighted)
MAXIMUM INPUT LEVEL	+24 dBu
INPUT IMPEDANCE	10kohm
LATENCY	N/A

CONTROL

CONTROLS AND INDICATORS (FRONT)	Per Channel: Volume Potentiometer.Per Unit (Applies to both channels): 80 Hz HPF Switch, 100 Hz LPF Switch, Bridge-Mono Switch, Limiter Switch and Auto-Standby Switch
CONTROLS AND INDICATORS (REAR)	N/A
CONTROL AND MONITORING	N/A
DIGITAL SIGNAL PROCESSING	N/A
PROTECTION CIRCUITS	Thermal protection, Over-Current Protection, DC Protection, HF Protection

ELECTRICAL

MAINS POWER INPUT	Universal Mains, 100-240V, 50-60 Hz
MAINS CONNECTOR	Standard IEC C14
POWER CONSUMPTION - STANDBY	0.4 W
POWER CONSUMPTION - IDLE	7.2 W
POWER CONSUMPTION - 1/8TH POWER / 8 ohm Load	38 W
POWER CONSUMPTION - 1/3RD POWER / 8 ohm Load	100 W

HEAT

HEAT GENERATED - STANDBY	1.4 BTU/hr / 0.3 kJ per hour
HEAT GENERATED - 1/8TH POWER / 8 ohm Load	43 BTU/hr / 11 kJ per hour
COOLING	Fan-Forced Air Cooling – Temperature-Dependent
FAN NOISE (ANECHOIC CHAMBER @ 1 m)	38 dB(A)

SIZE

RACK SIZE	1RU High and 1/3-Rack Width
DIMENSIONS (W x H x D)	125 x 44.5 x 330 mm (5.5 x 1.75 x 13")
WEIGHT	1.6 kg (3.5 lbs)
SHIPPING DIMENSIONS (W x H x D)	250 x 80 x 420 mm (9.8" x 3.15" x 16.5")
SHIPPING WEIGHT	3 kg (6.6 lbs)

ACCESSORIES

ACCESSORIES (INCLUDED)	Mains Cable, Feet, Euroblock/Phoenix Plugs, Rack Ears
ACCESSORIES (AVAILABLE SEPARATELY)	uRAK2 and WBQX300
OPTIONS	Dante Version Available - QX300D

QX300A

SPECIFICATIONS

INSTALLATION ACCESSORIES

uRAK2

WBQX300

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