The Head Box S USB from Pro-Ject is a class-leading audiophile headphone amplifier that offers a perfect upgrade to any headphone connection found on conventional amplifiers. Its high-quality audio components produce rich, colorful sound that place you in the midst of whatever musical performance you're listening to. With its simple integrated loop output, the Head Box S USB can be connected to the record output of your amplifier in-line without compromising the signal passed through to your recording device. The USB 1.1 input also allows you to easily connect any digital source via USB Audio. Pro-Ject's capable Head Box S USB will allow you to get the most out of your precious headphones, bringing the improved dynamics, natural sound, and detailed transparency necessary to elevate your music listening to the next level.