What headphone types can I connect to the HP4E?

Each of the four channels has two output sockets—a 3.5 mm (1/8") and a 6.3 mm (1/4") jack—so you can connect standard consumer headphones, professional studio cans, or wireless receiver packs. You can use both sockets on the same channel or split them across different headphone types depending on your setup.

Can I send different mixes to each headphone channel?

Yes. The HP4E has a single 6.3 mm (1/4") unbalanced input, but each of the four channels has an independent level control knob, so you can set the mix volume for each listener independently without changing what's being sent to the amp.

Is the HP4E portable enough for touring or mobile work?

Absolutely. It weighs just 760 g, occupies half a rack unit (1 RU), and ships with a standard 12V power supply, making it ideal for mobile rigs, fly-in gigs, and temporary installations. The sturdy metal chassis holds up to repeated transport and active use in demanding environments.

What audio specs should I expect from the HP4E?

The HP4E delivers up to 220 mW of output per channel with distortion below 0.05% and a signal-to-noise ratio better than 85 dB-A across a 20–20000 Hz bandwidth, ensuring clean, transparent amplification even at moderate-to-high listening levels. These specs make it suitable for professional studio tracking and live monitor applications where signal integrity matters.

How many people can use headphones at once?

Four independent channels, so up to four musicians, engineers, or playback operators can monitor simultaneously, each with their own volume control and choice of 3.5 mm or 6.3 mm connection.

AKG HP4E 4-Channel Headphone Amplifier

The AKG HP4E is a compact half-rack headphone amplifier designed to distribute independent mix feeds to four musicians, vocalists, or engineers during overdubs, ensemble tracking, and monitoring sessions. Its lightweight metal chassis and intuitive front panel layout integrate seamlessly into console-based workflows and portable mobile rigs. Built with AKG's reputation for reliability, this amp delivers clean, low-distortion amplification across four isolated channels without compromising signal integrity, preserving mix detail across headphone feeds.

Design & Build

Housed in a sturdy metal chassis in half 1 RU rackmount format, the HP4E weighs just 760 g and runs from a standard 12V power supply, making it ideal for both permanent studio installations and mobile session work. The compact footprint preserves valuable rack real estate in tight control rooms while its professional construction ensures years of dependable operation through intensive session schedules.

Studio Headphone Distribution

Each of the four channels features dual outputs—a 3.5 mm (1/8") socket and 6.3 mm (1/4") socket—accommodating everything from consumer earbuds to professional closed-back monitoring headphones with independent level control per channel. The amplifier delivers up to 220 mW maximum output with distortion below 0.05% and a signal-to-noise ratio better than 85 dB-A, ensuring transparent headphone mixes at comfortable monitoring levels across a 20–20000 Hz bandwidth, with minimal noise floor to capture the nuance of each performer's reference feed.

Key Features

Four independent headphone output channels with individual level control
Dual outputs per channel: 3.5 mm (1/8") and 6.3 mm (1/4") sockets
6.3 mm (1/4") unbalanced input
Input impedance: 100k Ohms
Output impedance: 11 Ohms
Maximum output level: 220 mW
Distortion: <0.05%
Signal-to-noise ratio: Better than 85 dB-A
Audio frequency bandwidth: 20–20000 Hz
Half 1 RU rackmount format
Sturdy metal chassis construction
12V power supply included; net weight 760 g

The HP4E remains an essential tool for any recording setup requiring simultaneous headphone distribution—multitrack sessions, ensemble tracking, overdub management, and teaching environments all benefit from its straightforward operation and solid engineering.

Condition	New
Country of Manufacture	China