Hey all - I’ll start by saying that I genuinely like my Manticore. My Deus II is more reliable in some cases, but the battery capacity and the need to charge 3 different things has me reaching for the Manticore more often in the past few weeks since I got it. That said, I really dislike the Manticore headphones. I don’t know if my head is just weird or if the earcups on these headphones are off, but they don’t sit flat against my head. They feel like someone took old Walkman headphones from the 80s and gave them larger earcups, but forgot to extend the foam all the way to your head. Then there’s the waterproofing issue. Before I even got my detector, I heard reports of Manticore headphones dying in Europe from rain and humidity. So here’s my thought: Headphones aren’t at all complex on their own. It’s really the wireless transmission bit that gets tricky. Minelab was kind enough to leave all the screws on these headphones exposed and to use a normal screw head. I might be able to find some components from a more comfortable (and durable) headphone online, then remove the speaker elements, the battery, and the wireless receiver from these headphones and move them over. The USB-C charge port shouldn’t be an issue if I pick another headphone that charges that way. The wired input locks, so I’d need to figure out the exact sizing and some way to manually route that out. Has anyone tried this? Taking the guts from a wireless detector headphone set and putting them in a more comfortable / more durable headphone body?
top of page
bottom of page
Video of them working!
https://youtu.be/0tww5egn9cM
I just finished my schematic for the Manticore headphones (attached). I'll start by stating that I did this mostly over a single day with only a little research done last week, so I could easily have missed something. I also am pretty burned out from trying to onboard 4 new engineering teams at my office, so my brain isn't firing on all cylinders right now - again, I may have missed something.
I don't know why, but for some reason, I thought the Manticore used a proprietary wireless communication mechanism and not Bluetooth (possibly because they never call out Bluetooth in the Manticore marketing and instead say, "low-latency wireless audio", or because they specify in the ML105 marketing that it has "higher quality audio than standard Bluetooth". Who knows?). However, the transceiver chip was a Bluetooth 5.2 transceiver available on Digikey and Mouser. I checked the FCC filing for the Minelab ML105 headphones, and sure enough, on page 6 of the FCC test results, it calls out:
Bluetooth Version V5.2
Modulation GFSK 1Mbps, GFSK 2Mbps
Number of Channels 40 Channels
On to the technique, tools, and materials: Tools / materials:
J0 and J1 Phillips head screwdrivers (plus others for your replacement headphone shell)
small flathead screwdriver / pry bar
Soldering iron
desoldering pump
desoldering wick
heat gun
scraper / knife
flux
1mm 2:1 heat shrink tubing
30 AWG wire
acrylic conformal coating
Epoxy
Epoxy Putty, Thermoplastic, or something else moldable
Rotary tool with carving bits (dremel, Ryobi, etc.)
Technique:
Opening the ML105s is pretty easy. Unscrew the two exposed screws on the hinges to the right and left sides of each earcup. This allows the earcups to disconnect from the headband. Remove the foam from the earcups by pulling lightly to expose a small gap at the perimeter, then using a small prybar/screwdriver to gently slide around and disconnect the pressure clips. Once the foam is removed, you will see 4 small Phillips head screws that hold the earcups closed. Once these 4 screws are removed, carefully turn over each earcup and allow the speaker element to fall out. It will still be connected with a wire.
Now comes the fun bit. I started by figuring out where the USB-C port was on my new headphone shell and ensuring that Board 1 would fit. It was close but not perfect. I was able to sand down the board a bit to make it fit without compromising any components / connections. Next, I determined where the buttons would be for each Vol -, Vol +, and Power. I did this using the original buttons from the ML105. I routed out holes for these and moved the buttons from the ML105s to their new home. I then used some epoxy putty to build supports for Board 1 so I could screw it down. I wanted to avoid ordering a new FFC cable, so I found a home for Board 2 that let me reuse the original cable. I turned everything on and checked where the LEDs would be most visible, then drilled a small hole in the earcup and filled it with clear epoxy to let the light shine out.
I originally tried to retain as much of the original wiring as possible, but it was just too small for me to strip and re-solder with my hands, so I desoldered the 6 wires on Board 1 and replaced them with new 30 AWG wires that I ran to the battery and each speaker. To avoid FULLY disassembling the new headphones (some parts were glued / taped in place), so I used the newly-soldered 30 AWG wires as jumpers and soldering them to the original wires for the Sony headphones I was using, then used heat-shrink tubing to protect the connections.
I just abandoned the 500 mAh battery from the ML105s. It was taped down VERY firmly and was also surrounded by a thin plastic border. I could either cut the border (and risk accidentally puncturing the battery), or try to leverage the battery out (and risk puncturing / bending the battery), so I opted to use the 1000 mAh battery from the Sony pair instead.
Lastly, before I screwed the 2 boards into their new homes, I coated both with acrylic conformal coating. This just adds a bit more weatherproofing. After that, it was time to close it all up! Marketing Notes: The Bluetooth 5.2 thing really bothers me here. Minelab's marketing for the Manticore and the ML105 headphones both intentionally make it sound as though Minelab is using something better than Bluetooth while not actually saying that. They claim "higher quality audio than standard Bluetooth". But what is "standard Bluetooth"? If I define standard as Bluetooth 5 or as BLE, then yes, Bluetooth 5.2 is definitely better. It's also possible that they're doing something proprietary by limiting the frequencies these headphones use to avoid interference with the detector, and I just don't understand. But at their core, these are Bluetooth 5.2 headphones, which puts them in the same class as headphones like the OneOdio A11, the Razer Barracuda Pro, or the Sony WH1000 XM5. And that begs the question, why not just let us choose the headphones we want? If BT 5.2 is good enough, give us a cheap pair of BT 5.2 headphones with the detector (like they did) and declare clearly in the documentation that Bluetooth headphones are generally supported but that Minelab cannoy guarantee the performance of 3rd party headphones and strongly recommends BT 5.2 or above to avoid latency issues.
Quick update - I did it! And it’s glorious! It took a lot of modifications to the headphone body and to the boards to make it all fit together, but I got the guts of the Manticore headphones into a pair of Sony WH1000-MX4s. The fit and comfort are perfect and the audio is better than ever thanks to the extra insulation on the Sonys. I don’t need to have the volume cranked up quite so high to hear over the wind and waves.
I took them out to the beach this afternoon for their first real world test and they are SUCH AN IMPROVEMENT!
Here’s what I gained: * double the original battery capacity
* improved noise isolation
* improved speaker elements
* improved comfort
* improved durability (no exposed wires)
* improved weather resistance
* smaller pack size
I’ll post some pictures of the end result along with a wiring diagram in the next few weeks.
Update - I decided to do a bit of “research” by tearing down my Manticore headphones and also a broken pair of Sony WH1000-MX4 headphones that I have on hand. I am decently certain I could get the Minelab headphone components to fit in the Sony shell and also provide a battery upgrade.
The Manticore headphones run off a 3.7v 500mAh Lithium Ion battery. The Sony runs on a 3.7v 1000mAh Lithium Ion battery that takes up almost exactly the same footprint. The main board for the Manticore headphones is a little larger than the Sony board, but the Sony also needed a significant amount of space for added wiring and sensors. The Manticore headphones are remarkably simple.