Control and flexibility for headphone monitoring
HPA is the Box Line headphone amplifier designed for professional monitoring in recording, broadcast and post-production. Its linear Class-AB architecture and output stage rated up to 9 V RMS / 450 mA RMS are paired with continuous volume control and practical functions designed for efficient headphone monitoring.
Stereo and mono directly from the panel
The STEREO / MONO control quickly switches between stereo listening and a summed mono signal, useful for compatibility and channel-balance checks.
Gain range adapted to the headphones
The H/L Z selector adapts the available gain range to the headphones being used, making volume adjustment more practical with lower- or higher-impedance models without changing the amplifier’s output impedance.
Connections and integration
Two balanced Combo XLR3F / 6.35 mm TRS line-level inputs integrate easily with audio interfaces, mixers and other professional sources. The power supply is fully linear, and an external 24 V DC power supply is included.
Applications
HPA is designed for vocal tracking, detailed editing, cue mixes and, more broadly, headphone-monitoring workflows in studios, broadcast and post-production.





