Review Lacking additional boxes, dangling wires or ear-dragging weights, Motorola's S9 is what a set of Bluetooth headphones ought to be - as long as your head is the right shape for them.
The problem with Bluetooth headphones is the need for bulk, mainly for the battery but also the receiving circuitry and controls - not to mention some sort of connection between the ears. Various designs have incorporated oversized ear pieces, dangling toggles and even 1970s style on-ear boxes to accommodate the necessaries.
Motorola's S9: bulging with electronics
The Motorola S9 gets round the problem by putting all the electronics in a bulge that rests on the back of the neck. Anyone with hair down to their shoulders will find the headphones almost invisible, though non-hippy types will find themselves sporting an apparent carrying handle, which friends and colleagues may find irresistible.
Other innovations are less welcome: while some headphones sport pads that rest on the ears and others fit snugly into the ear, Motorola has managed to make ear pieces that fit into the ear a bit - but not enough to offer any benefit. They offer all the comfort of ill-fitting in-ear headphones, without any muffling of external sounds that such 'phones normally provide. Three sizes of earpiece sleeves are supplied, but none of them seemed to fit our ears as well as they should have.
The unusual shape of the S9 is also non-negotiable. They don't fold up or compress in any way, but are at least robust enough to drop in the bottom of a bag without fear of damage.
Whether you find the S9 headphones comfortable will depend on the shape of your head. If it matches then they are very comfortable, otherwise it feels vaguely as though one's head is being held in a clamp for x-raying - not exactly uncomfortable, but a bit weird. The clamping effect may be down to the importance of their staying in place during exercise, and the rubber construction would certainly place them well in such an environment where the 'phones could easily survive sweat and knocks. The six-hour battery life was longer than anyone at Register Hardware could work out for, but an equivalent number of shorter sessions seemed to bear out the quoted capacity.
Once you get used to the shape the 'phones are as easy to use and operate as they should be. The bulge conceals a standard mini-USB connection for charging, and a power button which is held down for Bluetooth pairing. Once the S9 was charged we were paired up and working within seconds.