BasX A4 Four-Channel Power Amplifier

The BasX A4 is a four channel power amplifier that delivers 100 watts / channel into 8 Ohms and 130 watts / channel into 4 Ohms, all channels driven, with a rated THD+N of < 0.02%, and an A-weighted S/N ratio of 115 dB. The BasX A4 features a heavy-duty linear power supply, high-quality Class A/B amplification, transparent fault protection, and a trigger input and output. High quality industry standard unbalanced RCA inputs enable the BasX A4 to be used with almost any preamp or processor and audiophile grade five way speaker terminals accept banana plugs, spade lugs, or bare wire. These features combine to enable the BasX A4 to deliver true audiophile performance and sound quality at an amazingly affordable price.

The BasX A4 is the perfect solution if you need a high quality amp to power your Dolby Atmos and DTS:X height channels. It is also an excellent choice to power your surrounds if you're building a new system and you've already committed to a more powerful amp, like our XPA-3, to power your front channels or to power two pairs of zone speakers.

Sound Quality First

• Designed first and foremost to sound great in all types of audio systems with all types of music.
• Great sounding Class A/B output stage ensures smooth, detailed sound and incredibly natural imaging, without a trace of harshness or strain.
• Low noise, wide bandwidth design, and a highly optimized input stage, lets you hear everything your high definition sources have to offer.
• Totally stable with real world speakers in real systems; not just on a test bench.

Solid Engineering And Quality Construction

• A heavy duty linear power supply with an oversized toroidal power transformer delivers plenty of current to drive even difficult speakers.
• Top quality parts and construction throughout deliver years of reliable trouble-free service.
• Heavy steel chassis with milled aluminum faceplate offers strength and rugged good looks.
• Double sided FR4 circuit boards, with plated-through holes, help optimize signal paths and minimize the need for point-to-point wiring.

Flexible Signal Connections and Power Options

• Unbalanced inputs via industry standard RCA connectors accept all standard unbalanced interconnects.
• Heavy duty insulated five-way speaker binding posts allow you to use a wide range of speaker cables with bare wires, lugs, or banana plugs.
• Remote trigger input and output allow the BasX A4 to control and be controlled by other trigger-enabled equipment.
• The BasX A4 is designed to operate on either 115 VAC or 230 VAC at 50/60 Hz and will automatically detect and configure itself for the proper line voltage.

Stylish New Look

• Our redesigned front panel gives the new BasX A2 a sleek modern aesthetic that fits well with virtually any room décor.

Strong Yet Silent System Protection

• Audiophile-grade fault protection is entirely transparent under normal listening conditions, yet protects the amp and your other equipment from virtually all common faults.
• Full three-year warranty ensures that you’ll be able to enjoy your BasX power amplifier for years to come.

Circuit Topology

• The BasX A4 is a four channel power amplifier. The BasX A4 combines classical audiophile amplifier architecture, based on a heavy-duty linear power supply, and a carefully designed high current short signal path Class A/B output stage, with advanced microprocessor-controlled monitoring and protection circuitry, to deliver superb sound quality at a truly reasonable price.

Audio Specifications

• Power Output (ALL channels driven):
  100 watts RMS per channel; 20 Hz – 20 kHz; THD < 0.1%; into 8 Ohms.
  130 watts RMS per channel; 1 kHz; THD < 1%; into 4 Ohms.
• Power Output (two channels driven):
  120 watts RMS per channel; into 8 Ohms.
  175 watts RMS per channel; into 4 Ohms.
• Power Bandwidth (at rated power; 4 Ohm - 8 Ohm load): 20 Hz to 20 kHz (+ / – 0.02 dB)
• Broad Band Frequency Response: 10 Hz to 80 kHz +0/-1.8 dB
• THD + noise: < 0.02% (A-weighted); ref rated power
• Signal to Noise Ratio (8 Ohm load):
  > 115 dB; ref rated power; (A-weighted).
• Minimum Recommended Load Impedance (per channel): 4 Ohms
  (which equals one 4 Ohm load or two paralleled 8 Ohm loads).
• Damping Factor (8 Ohm load): > 500.
• Input Sensitivity (for rated power; 8 Ohm load): 1.2 V.
• Gain: 29 dB.
• Input Impedance: 27 kOhms.

Input And Output Connections

• Input Connections: Unbalanced (RCA); one each per channel.
• Speaker Output Connections: Audiophile grade 5-way binding posts.
• Trigger:
  Trigger Input: 5 – 12 V (AC or DC); <10 mA input current required.
  Trigger Output: 12 VDC; can drive any load up to 120 mA.

Power Requirements

• 115 VAC or 230 VAC @ 50 / 60 Hz (automatically detected).

Front Panel Controls and Indicators

• Standby: push button.
• Status LEDs: one per channel; blue.
• Status LEDs change to red to indicate a fault condition.
• Standby LED: amber.

Rear Panel Controls

• AC Power switch: rocker switch (switches AC main power).
• Status LEDs switch: disables front panel Status LEDs.

Protection

• The BasX A4 is protected against excessive operating temperature, shorted speaker connections, ground faults, and other common fault conditions.

Mechanical

• Dimensions:
  17” wide x 4” high x 15-1/2” deep (not including connectors).
  21-1/2” wide x 8” high x 21” deep (boxed).
• Weight:
  26 lbs (unboxed)
  32 lbs (boxed)

Downloads

Download Product Manual