A Bluetooth headset featuring a detachable earpiece cable, the Plantronics Voyager 855 is a dual-function device capable of making and receiving phone calls and streaming stereo Bluetooth audio.

The Voyager 855 consists of two parts – a Bluetooth headset and a detachable earpiece. If you are just using it for phone calls, then it acts as a regular headset. The sliding boom microphone means that voice quality is improved thanks to the microphone being close to your mouth. Conveniently, sliding the microphone also answers and ends calls but although the slider feels smooth, sliding it makes the earpiece feel loose in your ear – especially if you aren't wearing the ear hook.

The Voyager 855 features AudioIQ technology, a digital signal processing (DSP) feature that automatically adjusts sound levels depending on the level of outside noise. The result is clear, crisp, natural sounding audio – both incoming and outgoing audio is excellent. Our callers voice was clear and at notable volume, while callers didn't complain of any issues with outgoing voice.

The Voyager 855 is quite easy to use, with a single call handling button, volume controls and a dedicated mute button. Pressing and holding the call handling button puts the unit into pairing mode (denoted by the indicator light flashing red and blue) and once paired, functions are simple and easy. Press the call handling button or slide the boom microphone to answer a call and press it again or slide the boom closed to end the call. Additional functions include activating voice dialling (provided this is supported by your phone), transferring a call from the headset to your phone and muting the microphone.

The detachable earpiece looks like a regular ear bud, but it's attached to an ear hook via a cable. A small slot at the back of the headset connects the cable and automatically allows the Voyager 855 to stream wireless, stereo audio via A2DP. Unfortunately, the quality of audio streaming isn't anywhere near as impressive as call quality – sound is passable, but far from outstanding, with a lack of crispness and poor bass reproduction the main issues. We also found the controls a little small for music playback, especially the tiny mute button which is used to play and pause your music.

Aesthetically, this is one of the better looking Bluetooth headsets on the market. Although it's quite long (especially with the microphone opened), the gloss black and silver finish adds a touch of class. You can wear the headset without an ear hook, but we preferred the hook as it felt much more secure. The soft rubber ear buds means the Voyager 855 is comfortable to wear for long periods, and the package includes small, medium and large sized ear buds, in addition to an ear hook without the stereo ear bud.