The HPA-4X2 4-Channel Stereo Reference Headphone Amplifier from Polsen features a durable and compact design and can be used for a variety of professional and project applications including studio recording and stage monitoring, or any application that requires multiple headphone connections. Features include a wide frequency response of 20 Hz to 20 kHz with low distortion at high volumes, and no signal loss when all 4 headphone outputs are used simultaneously. Each of its four channels allows for independent volume control. Thanks to its Link feature, you can daisy chain multiple HPA-4X2s together to cater to your needed headphone count.

The unit features a 1/4" stereo TRS input, and stereo RCA inputs. It mono button allows for mono signal compatibility. For its headphone outputs, it features four 1/4" TRS connectors. To assure compatibility with a variety of headphones, Polsen includes four 1/8" to 1/4" adapters as well as a stereo mini cable that, when used with one of the included adapters, allows you to connect a device with a 1/8" output.