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Quest QA4004 2 Channel Amplifier

Regular price $3,432.17

Tax included.

QA Series Power Amplifier

QA1004 [2x 575w @ 4Ω] – QA2004 [2x 870w @4Ω] – QA3004 [2x 1100w @ 4Ω] – QA4004 [2x 2000w @ 4Ω]



Quest QA Series power amplifies are built to work hard in the tough environment of pro audio. Industrial spec multi-speed fans and generous heat sinks will keep the output stage cool even if the amplifier is installed in a dusty and poorly ventilated area.

Service and maintenance is easy as the internal architecture is laid out for easy access by a qualified technician. The sonically superior output stage is composed of a generous abundance of output devices for greater electronic stability and sonic fidelity.

QA series amplifiers are manufactured to a standard accepted as desirable practice for a concert standard power amplifier. Heavy gauge welded 16-gauge steel chassis with vibration proof fittings, and an emphasis on over-engineering, guarantees years of trouble-free service in the most demanding environments.

Quest set about a design and layout for easy service, not easy manufacture. A minimum of disassembly is required for testing and maintenance meaning lower operating costs and longer amplifier life.



  • Input Stage: Pro active protection senses stages of system function to safeguard your investment both on turn on and while under operation. Silent switch on/off circuitry reduces potential speaker damage in the event of intermittent power.
  • Power supply: The high current power supply is manufactured to function reliably at high temperatures and well exceeds industry standards. This results in smooth bass response and considerable dynamic headroom.
  • Industrial Spec Fans: Dual heavy duty cooling fans guarantee long life of all electronic components.
  • Input Connection: XLR parallel male and female input connections calibrated for most pro spec system controllers and electronic cross-overs. features
  • Speakon Connections: International AES standard Speakon connectors wired for two channel operation simplify speaker connections.
  • Limiter: A switchable high speed limiter acts as a final speaker protection but can be disconnected where sensing speaker system controllers are required.
  • Built in switchable X-overs: High Amplification and low pass filters on each channel make the versatile QA series even more flexible with a sub-mid/high frequency dividing network.
  • Selectable Gain settings: Adjustable input switching for 0.775V, 32 dB or 26 dB make system calibration easy.
  • Easy access air filters: User serviceable air filters are easy to maintain for trouble free operation.



  QA1004 QA2004 QA3004 QA4004
  2x 575-w at 4Ω 2x 870-w at 4Ω 2x 1100-w at 4Ω 2x 2000-w at 4Ω
Rated Power 
(2x 8Ω):
290-W per channel @ 1kHz at <0.1% T.H.D. both channels driven 490-W per channel @ 1kHz at <0.1% T.H.D. both channels driven 660-W per channel @ 1kHz at <0.05% T.H.D. both channels driven 993-W per channel @ 1kHz at <0.05% T.H.D. both channels driven
Rated Power:
(2x 4Ω):
575-W per channel@ 1kHz at <0.1% T.H.D. both channels driven 870-W per channel @ 1kHz at <0.1% T.H.D. both channels driven 1100-W per channel @ 1kHz at <0.05% T.H.D. both channels driven 2400-W per channel @ 1kHz at <0.05% T.H.D. both channels driven
T.H.D: <0.1%@250-W per channel from 20 HZ to 20kHz <0.1%@400-W
per channel from 20 HZ to 20kHz
<0.5%@400-W per channel from 20 HZ to 20kHz
Phase Response: +5 to -15 from 20 Hz to 20kHz +20 to -25  from 20 Hz to 20kHz
Input Impedance: 20 kΩ, balanced; 10 kΩ, unbalanced
Cooling: Two temperature dependant variable speed 80mm high-output DC fans Two temperature dependant variable speed 120mm high-output DC fans
Controls: Two front panel attenuators, rear panel mode switch and gain select switch
High Pass: Linkwitz-Reily (24 dB/Octave): Off/35/80 Hz
Low Pass: Linkwitz-Reily (24 dB/Octave): Off/80/110Hz
Voltage Gain @ 
 29 dB or 24 dB 32 dB or 26 dB 35 dB or 29 dB 38 dB or 32 dB
Crosstalk: >-60 dB @ 1kHz at rated power @ 8Ω
Hum and Noise: >-105 dB, "A" weighted referenced to rated power @ 8Ω >-107 dB, "A" weighted referenced to rated power @ 8Ω
Slew Rate: >30V/us >40V/us >44V/us
Damping factor (8Ω): >500:1 @ 20Hz - 1kHz >700:1 @ 20Hz - 1kHz >800:1 @ 20Hz - 1kHz
Indicator LEDs: Two clip, two signal presence, one active status, two protection
Protection: Thermal, DC, turn-on bursts, subsonic, incorrect loads
Connectors: XLR . Speakon . 240/230 Volt 16 amp IEC mains
Construction: Cold Steel Rolling + Machined aluminium front panel
Dimensions (HxWxD): 89mm x 483mm x 496mm 132 mm x 483mm x 496mm
Net Weight: 17kg 21kg 23kg 35kg
Packaged Shipping Weight: 20kg 23kg 26kg 38kg