Tofty Headphones 2: Bluetooth Open-Backs

This is my second attempt at a mostly printed set of headphones. An improvement over my initial version, this one has an open-back design and utilises a Fiio BTR3 bluetooth receiver/DAC to make them wireless. There's still plenty of improvements that can be made, but these work reasonably well.

The included Solidworks and .STEP files contain most o the details as to how it is all meant to go together, but a few details might be a little opaque, so please feel free to ask any questions you may have.

The earpads are 110x90mm ovals, but the pads I got ended us being a bit loose, so the driver plate part could do with enlarging slightly.
The drivers are just a standard 50mm type.
The headband came from a specific set of headphones, so this detail will definitely need to be redesigned.
The wiring in these has been simplified down to just one internal connector, but that could be removed if desired.
External connectors are Mini XLR 4 Pin connectors and 4 Pole 3.5MM audio jacks.
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