Sennheiser RS 120 II

The Sennheiser RS 120 II is not a headphone alone but an inseparable pair: a transmitter base, connected to a domestic source, and an open-back on-ear receiver headphone. The connection between the two is cable-free, which completely shifts the way it is used: you can leave the listening chair without removing the headphones, and continue hearing the film while moving from one room to another.

The stated range of around 100 metres explains this freedom of movement. In practice, it comfortably exceeds the volume of a living room and covers an entire home, including an adjoining terrace or garden. The transmitter relies on Sennheiser's proprietary wireless technology, whose aim is to preserve the quality of the transmitted signal rather than settling for mere convenience.

In terms of sound, the RS 120 II aims for neutrality: a transparent signature, a tonal balance without marked emphasis on any register, and bass reproduced with authority. This approach suits the product's dual purpose well, both for music listening on a hi-fi system and for following dialogue and soundtracks on television. The on-ear construction, with cushions resting on the ear rather than surrounding it, contributes to the overall lightness, and the headband design has been conceived for extended listening sessions.

One point clearly sets this model apart: the same base can power several HDR 120 headphones in parallel. Two people can therefore listen to the same programme simultaneously, each with their own headphones, without needing a second transmitter. This is a decisive advantage for shared evening listening, or for adding a second headphone to an existing setup. The RS 120 II is thus aimed at anyone who wants to listen late without imposing the volume on the rest of the household, and at anyone who refuses to be tethered to their amplifier by a cable.

When buying used, several points deserve particular attention with this type of equipment:

• The headphone's rechargeable batteries: these are consumables that lose capacity over the years, and their replacement determines the actual usability of the unit.
• The charging contacts, on the headphones as well as in the base's cradle: if oxidised or misaligned, they prevent charging even though everything else works.
• The pairing between the headphones and the transmitter, to be checked under real conditions, along with the stability of the connection at a distance and through a wall.
• The foam of the on-ear cushions and the headband covering, which harden, crumble or tear before anything else on this type of headphone.
• The actual presence of the transmitter base and its power supply, without which the headphones alone remain unusable.

One final useful check: if the lot includes several headphones, test each one separately on the base, as a single faulty receiver can go unnoticed during a quick trial.