HEADPHONE/LINE AMPLIFIER

Benchmark HPA4 – Headphone/Line Amplifier

The HPA4 features the Benchmark-exclusive THX-888 headphone amplifier. This is Benchmark’s flagship headphone amplifier. It also marks the pinnacle of the THX headphone amplifier family. The THX-888 circuit board is manufactured by Benchmark.

Like our AHB2 power amplifier, the THX-888 features the patented THX-AAA feed-forward topology. The THX-888 keeps noise and distortion below the threshold of hearing, even when driving the most difficult headphones.

The award-winning HPA4 packs power, speed, and control into a package that includes all of the functions and features of our LA4 line-level preamplifier.

The headphone and line outputs are controlled by independent 256-step relay-switched attenuators. This is, without question, the best analog volume control system available.

Feed-Forward Error Correction
Much Faster than Feedback
Eliminates Zero-Crossing Distortion
Inherently Stable, Non-Recursive Correction
Stable into Any Phase Angle
Stable when Driving Very Low impedances
No Rise in THD when Driving Low Impedance Headphones
Patented THX-AAA Technology
Flagship THX-888 Headphone Amplifier
30 to 40 dB reduction in THD
Keeps THD+N Below 0 dB SPL at All Times
No “Electronic Fingerprints” on the Music
Accurate Impulse Response Into all Loads
135 dB SNR
Extended Frequency Response
Ultra Wide 0.1 Hz to 500 kHz Response
Bass is Delivered Without a Phase Shift
Fast, Distortion-Free Transient Response
Linear Phase Response
Accurately Reproduces the Audio Waveshape
Precise Rendering of Stereo Width and Depth
Focused 3-D Stereo Image
Unique Features
High Output Current – Drives Low Impedances with Ease
High Output Voltage – Ample Headroom to Dive Inefficient Headphones
0-Ohm Output Impedance – Maintains Tight Control of Drivers
Fault-Detection Circuit- Protected against Short Circuits and Overloads
Dual Outputs – XLR4 and 1/4″ TRS
Independent Line and Headphone Balance Controls
Relay-Controlled Volume
High-Precision Low-Impedance 256-Step Attenuator
Low-Noise 16-Step Input Gain Stage
Control Range is +15 dB to -127.5 dB in 0.5 dB Steps
High Precision Laser-Trimmed Thin-Film Resistors
12 Relays per Output – 48 Total Including Line Outputs
Precision Make-Before-Break Timing – Prevents Switching Noise
Fully-Balanced LA4 Line Amplifier
The HPA4 Includes all LA4 Features
2 Pairs of Balanced Line Inputs
Fully-Balanced Differential Input Amplifiers
Fully-Balanced Relay-Controlled Gain Stage
Fully-Balanced Relay-Controlled Attenuation Stage
Fully-Balanced Output Line Drivers
Left, Right and Mono – Balanced Line Outputs

DESIGNED, ASSEMBLED, AND TESTED N THE USA

This Benchmark product was designed, assembled, and tested in the USA using USA and imported components. Most major components are made in USA.