Long Lasting Wireless Headphones

Hello Community !

So, I had this headphones sennheiser urbanite, If you have ones, you know that they have rubberish kind wire which just rubber with time and stopped working. Also, I found that there is other version of those called sennheiser urbanite XL which are also wireless. That made me think. Can I make mine wireless ? I started with opening them and I discovered that there was plenty of space inside.... so... lets start.

• sennheiser urbanite or any other headphones with some space inside.
• csr8635 Bluetooth module chip
• 2400 mah lipo battery
• usb type c charging module tp4056

First, let me apologize, this is not very beautiful way of assembling parts, but Im not so good at it. CSR module is horribly difficult to solder wires to, as I had very basic soldering iron.

In Right headphone I placed the battery. I managed to fit inside 2400 mah with following dimmensions 40x50x10mm. I had to use dremel to remove some plastic elements and in addition, I had to remove plastic speaker cover. That was not ideal option as probably I disturbed sound acoustics properties but after testing they still sounded okay. Then and only I was able to fit this monster battery. In the left speaker compartment I placed CSR BT chip, it is behind breadboard (sorry for unclear picture), small pushbutton, and additional power switch. There is also blue status LED. I was extremely lucky, because little plastic element where speakers are attached, are empty inside, and I can fit charging module ( of course with little help of dremel ). Wires are placed inside white element that joins two speakers. Pushbtton is responsible for powering BT chip and mechanical switch is for power cut off from battery as additional safety. CSR chip allows also to connect control and volume pushbuttons as well as microphone, but I gave up due to soldering difficulties.

When it comes to CSR pinout its very simple:

SPK_AP - left speaker positive

SPK_AN - left speaker negative

SPK_BP - right speaker positive

SPK_BN - right speaker negative

GND - ground

VCHG - voltage input

LED1 - led output

Thats it. No amplifier etc etc.

Ok, so now, most important info. How long does the headphones last with most unusual 2400 mah battery ?!

I found that long playing headsets like Infinity Glide 510 headphones are able to play up to 72 hrs of play time having 610 mah battery.

Buckle up your seat belts, because with mine configuration I was able to play music 165 Hrs with mixed volume levels.

If you have some questions, feel free to ask.

Thanks !