DT770 Bluetooth mod

cults3d

This is a mod for the Beyerdynamic DT770 headphones that adds Bluetooth without a little brick dangling off your head. That said, it is not for the faint of heart. There will be a lot of soldering, and you'll want to make changes to the CAD and do a few test prints of your own if you want good results. Read further down for more info. === Flaws === Firstly, you should know what you're getting into. To be honest, this whole thing is pretty half-baked. building it is a pain in the ass, the buttons barley stay in, and it looks kinda stupid. There are F3D files for a reason. The holes that interface with the retention clip on the right side need to be flipped. The clip still goes in and holds pretty good, but sticks out a bit and makes a noticeably asymmetrical fit. This is a problem that I solved with a dremel, but it's not too late for you to solve it with CAD. There were also no aesthetic considerations when designing these. If you plan on wearing these outside your home, make some changes to the exterior. Please. === finding a board === The current design is built for the board out of a JBL 510BT headset, because that's what I had lying around. The only parts of this design specific to that board are the buttons, the 4 positioning posts, the hole for charging, and the dimensions of the cutout for the battery. all of these things can be deleted from the design in a single click. You could go and buy a pair of 510s just for this build, but the design could easily accommodate any other board that has roughly the same dimensions. I would encourage you to scrounge around and find a pair of suitable pair of donor headphones, then modify the design to fit your board. the switch and the aux port were ripped out of an old DVD drive I had lying around. There's gotta be some useless thing with both of these sitting around your house. Adapt. Improvise. Overcome. === Disassembly of stock headphones === Unscrew the cups from the brackets and unbutton the head cushion to get the wire out. All the guts in a stock DT770 are held in by a circular retention clip buried beneath the ear pad. Pull of the ear pad and use a small screwdriver or a spudger to pry the clip out of the chassis. De-solder all the connections. === Wiring === For my setup, I needed 8 wires going from one side to the other. So, I grabbed a random Ethernet cable and cut it to length. You might be able to get away using a bit of USB cable if you just need to do a speaker and battery, For switching between Bluetooth and aux, both the drivers' ground wires go into a switch that connects them to either the ground on the BT board, or the ground on the headphone jack. Positive leads just branch out and connect to both inputs. Use very thin gauge of wire for this, because the wires coming off of the cable need to make their way around the driver and through the hole into the upper compartment. I used 22 gauge and that was still pretty cramped at times. === Assembly === Start with the electronics. All the electronics are just held in with a couple dots of hot glue. Make sure you don't get anything inside the aux port or switch, and you can easily detach hot glue using rubbing alcohol if you mess up. I would recommend putting the drivers on some kind of connector. I just used a 2 pin DuPont, but something smaller would be ideal. When putting the drivers in, start with just the plastic crown that sits on the back of the drivers. get all the cables routed around it, then put in the drivers. you may need to clip 1 or 2 of the segments short so that the wires can get through the opening to the upper compartment. Clip in the drivers, and seal the upper compartment opening with some hot glue. Then, you can put on the top covers. Use the notch in the rim to put on the ear cups, then screw the cups back onto the bracket and run the wire. With that, you're done! You may now run free as the wind, uninterrupted by your head-cans getting yanked off your noggin.