Earphone cable issue inspires Bluetooth conversion
[adblu] Had the ubiquitous headphone problem with their Sennheiser Urbanite headphones – the cable broke. These headphones are decent and, despite the cable issues, worth giving them a new lease of life. Cable replacement is always an option, but [adblu] decided to see – what would it take to make these headphones wireless? And while they’re at it, how much battery life could they get?
Armed with a CSR8635 Bluetooth audio receiver breakout module and a TP4056 charger, [adblu] continued to rewire the internals of the headset. The CSR8635 already has a speaker amplifier inside, so connecting the headset speakers didn’t take much effort – other than general soldering difficulties, like [adblu]The soldering iron was too big for the small pads of the BT module. They also found a 2400mAh battery and installed it inside the headphone body after generous amounts of Dremel work.
The result didn’t disappoint – not only does everything fit into the headphones’ body, but the headphones also offer 165 hours of music playback at variable volume. From an electronics perspective, it’s really easy to retrofit your earphones with Bluetooth, but you can always take it a step further and design a complex set of custom circuit boards! If firmware hacks are more to your liking, you can use a CSR8645 module for your build and then modify its firmware.