Coros takes a SafeSound approach to bike helmet audio
Back in 2016 we first heard about the Bluetooth-equipped Coros Linx bike helmet, which streams audio from the user's smartphone to bone conduction transducers in the head straps. Well, Coros is now trying something different and reportedly better, with its SafeSound line.
Bone conduction transducers work by converting sound waves into vibrations that pass through the user's cranial bones, bypassing the eardrum and transmitting directly to the cochlea – it's the sensory organ that translates sound into nerve impulses for the brain to interpret.
On the Linx, a couple of the transducers are located on the straps just in front of each ear, where they buzz the wearer's cheekbones. This leaves the ear canals open to hear important sounds such as traffic noise. When taking phone calls, the user's voice is picked up by a wind-resistant microphone in the front of the helmet.
Instead of bone conduction, the new SafeSound helmets use what is known as the Ear Opening Sound System (EOSS). This replaces the transducers with what are essentially tiny water-resistant speakers with openings in the back, that funnel sound into the ear canal while still leaving that canal open.
A Coros rep tells us that as compared to bone conduction, EOSS has less sound leakage, the straps don't need to be as tight against the skin, there are no vibrations, the volume can be set higher, and it accommodates a wider variety of head shapes.
Wearers utilize an included wireless bar-mounted remote to adjust volume, skip music tracks, take/end phone calls, and perform other tasks. That remote can also be used to power up and switch between modes on an LED tail light that's built into the helmet.
In the event of an accident, sensors in the helmet detect the telltale impact. This triggers an accompanying app to send an alert to people on a predetermined emergency contacts list (that alert including the user's current GPS coordinates), plus it causes the tail light to start flashing in a Morse code SOS pattern. The Livall smart helmet offers similar functionality, as does the ICEdot Crash Sensor, which can be installed on third-party helmets.
Prospective buyers can choose between Urban, Road and Mountain versions of the Coros SafeSound helmet, priced at US$180, $200 and $220 respectively. They weigh between 300 and 340 grams – depending on the model and size – with battery life sitting at a claimed maximum 10 hours per charge.