The LD Systems HPA 4 is a compact and versatile 4-channel headphone amplifier designed for professional and home studio use. Here’s a detailed description:

Channels: It features four individual headphone outputs, each with its own volume control, allowing multiple users to monitor audio with personalized levels.
Audio Quality: The HPA 4 delivers clean, clear sound reproduction with a wide frequency response, ensuring accurate monitoring for mixing or recording.
Input/Output: The unit provides one stereo 6.3 mm TRS input for connecting the audio source and four 6.3 mm TRS headphone outputs for distribution to up to four pairs of headphones.
Power: The amplifier is powered by an external power adapter (included), offering stable power and performance.
Build Quality: The HPA 4 is built in a rugged metal housing for durability, with a compact design that makes it easy to integrate into any studio setup.
Compatibility: It is compatible with a wide range of headphone impedances, making it a flexible tool for various headphones and listening scenarios.

Product type

Headphone Amp:

Inputs: 2
Input connectors: 6.3 mm TRS, RCA
Input impedance: 1 k Ohm(s)
Outputs: 2

Output connectors: 6.3 mm jack

Power output: 4 x 100 mW

Minimum connected impedance: 10 Ohm(s)

Frequency response: 20 - 20.000

Controls: 4 x headphone volume, Mono/stereo switch

Indicators: Power

Power supply: External Power Supply

Operating voltage: 24 V DC

Cabinet material: Metal

Cabinet surface: painted

Width: 94 mm

Height: 48 mm

Depth: 82 mm

Weight: 0,27 kg

Accessories (included): Power supply

LD systems HPA4