Benchmark Media Systems
HPA4 Headphone Amplifier and Preamplifier
Best reference amplifier for audiophiles demanding absolute signal transparency and power.
The Benchmark Media Systems HPA4 is a versatile 2U half-width audio component that combines a high-performance line amplifier with a powerful THX-888 headphone amplifier. It offers precise control over both stereo monitor systems and demanding headphones, including planar magnetic types. Featuring multiple analog inputs and outputs, a user-friendly touchscreen interface, and an optical encoder for volume control, the HPA4 ensures exceptional audio clarity and transparency. Its advanced circuitry provides a wide frequency response and an extremely low noise floor, making it an ideal centerpiece for professional audio setups. The Benchmark HPA4 is a versatile 2U half-width audio component that combines a high-performance line amplifier with a powerful THX-888 headphone amplifier. It offers precise control over both stereo monitor systems and demanding headphones, including planar magnetic types. Featuring multiple analog inputs and outputs, a user-friendly touchscreen interface, and an optical encoder for volume control, the HPA4 ensures exceptional audio clarity and transparency. Its advanced circuitry provides a wide frequency response and an extremely low noise floor, making it an ideal centerpiece for professional audio setups.
$2999.00
Owner Satisfaction
4.8
/ 5
Category Rank
1
/ 731
Best Headphone Amplifiers
Price vs Category Average
+115%
Above average
Form Factor
2
/ U half-width rackmount
Who it's for
- Audiophiles seeking absolute sonic accuracy and detail
- Listeners needing a high-end preamp and headphone amp combo
- Users requiring perfect channel balance at any volume level
Who should skip it
- Budget-conscious buyers looking for entry-level audio gear
- Listeners preferring the colored warmth of tube amplifiers
- Casual listeners with modest setups seeking value over precision
Performance breakdown
Signal Transparency
Industry-leading noise floor ensures absolute sonic purity and zero coloration.
Drive Capability
Effortlessly powers even the most demanding planar magnetic headphone loads.
Volume Precision
Relay-controlled gain offers granular, perfectly matched steps for every listening level.
Build Integrity
Milled aluminum construction provides a robust, professional-grade chassis for long-term reliability.
Interface Usability
Touchscreen navigation makes source selection and system adjustments intuitive and fast.
System Versatility
Comprehensive I/O options allow seamless integration into complex high-end audio chains.
Key Specs
Form Factor
2U half-width rackmount
Amplifier Technology
THX AAA
Inputs
2x Stereo Balanced XLR (up to +24dBu), 2x Stereo Unbalanced RCA (up to +12.2 dBu)
Outputs
L/R XLR, L/R RCA, Summed (L+R) mono output
Headphone Outputs
1x 1/4" TRS, 1x XLR4
Number of Headphone Outputs
2
Frequency Response
0.1 Hz to 500 kHz
Signal-to-Noise Ratio
> 135 dB
Features
- Combines line amplifier and headphone amplifier in one unit
- THX AAA technology for superior headphone amplification
- Drives difficult-to-drive headphones, including planar magnetic types
- Precision analog signal path with differential amplifiers
- Intuitive touchscreen interface for source selection and settings
- Optical encoder for precise volume control
- Automatic input level adjustment for balanced and unbalanced sources
- High-resolution audio reproduction with exceptional clarity and detail
- Revolutionary THX AAA™ technology for unparalleled linearity and low distortion.
- Ultra-quiet performance with an exceptionally silent background.
- High-resolution analog relay gain control with 256 steps for precise volume adjustment.
- Versatile connectivity with balanced and unbalanced inputs and outputs.
- Robust protection systems to safeguard headphones and the amplifier.
- Seamless system integration with other Benchmark components and standard trigger systems.
What customers say
Customers consistently praise the HPA4 for its exceptional sound quality and remarkable transparency. Users frequently highlight its ability to deliver an incredibly clean and precise audio signal, revealing intricate details in music without coloration. This amplifier is widely regarded for its robust build and unwavering reliability, ensuring a premium listening experience over time. Its performance is often described as reference level, making it a standout choice for discerning audiophiles seeking sonic purity and dependable operation.
Know before you buy
No, the HPA4 is a pure analog component. It functions as a high-performance line amplifier and headphone amplifier, so you will need an external DAC to process your digital audio sources.
Yes. With 6 watts of power into 16 ohms and a robust THX-888 amplifier design, the HPA4 is specifically engineered to handle the low impedance and high current requirements of planar magnetic headphones with ease.
The HPA4 uses a high-resolution relay gain control system with 256 steps in 0.5 dB increments. This ensures perfect channel balance and precise volume adjustments that remain consistent regardless of the setting.
Absolutely. The HPA4 features both balanced XLR and unbalanced RCA line outputs, allowing it to serve as a transparent, high-fidelity preamplifier for your stereo monitor or speaker setup.
The unit includes comprehensive protection systems, including short-circuit, DC, over-voltage, over-current, and thermal protection. These safeguards are designed to protect both your headphones and the amplifier circuitry from potential damage.
While the 3.5-inch touchscreen provides an intuitive way to select sources and adjust settings, you can also use the optical encoder knob for tactile volume control. Additionally, the unit supports an optional IR remote control for convenient operation from your listening position.
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