Make Your Own Rock Band Ekit Adapter (without Legacy Adapter), Nondestructively!

2023 Update - I was made aware that Roll Limitless now supports Xbox instruments. Since Harmonix doesn't seem like they're going to produce any more RB hardware and tearing them apart is inherently risky, I would recommend you go that route. Hope this guide comes in handy to someone, keep on rocking!

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After hearing a popular podcast host mention his concern about his wired USB legacy adapter dying, I went looking for a DIY solution to hooking up a better/custom eKit to RB. Thanks to Mr DONINATOR on Youtube who made a video detailing his similar project that inspired this.

My one concern was having to potentially modify the now relatively hard to find RB4 drum kit, or worse break it entirely as part of the process. This guide is non-destructive and can be completely reversed if you want to sell your plastic instruments for retirement money in a couple decades.

In total this cost me $150-200 to make in hardware. Even with the Alesis Nitro it totaled around $500, around half of the wired legacy accessory adapter on eBay!

Pros

• Non-destructive
• Cheaper than a legacy adapter
• Fully working
• Having the mechanical drum pedal makes playing so much cooler

Cons

• If you follow my initial method using an Arduino for the kick pedal, it needs power and in the interest of time I’m using a separate power cable. I recommend unplugging the Arduino when it’s not in use. This also prevents you from holding down the pedal to sort songs.
• DIY and time

This project is still a work in progress and a lot of firsts for me including Fusion 360 and Arduino!

Make sure you know your kit and measure twice, cut once when working on assembling everything. I’ve confirmed this works with an Alesis Nitro Mesh, if you’ve tried this with a different kit and it works let me know and I’ll add it here! Same goes with settings on the Arduino, I’m still getting back into RB after a long break so can’t attest to it working perfectly on devilishly difficult songs.

Confirmed working

Alesis Mesh Nitro ✅

Roland TD-1K ✅

The exact parts may change as the project develops, check to make sure your drum kit uses 1/4” connectors before buying anything! If you're happy with the stock RB drum pedal you can skip the pedal adapter and just make the case for the cymbals/toms/snare.

Parts

1x Working RB drum kit - The case is designed for Xbox RB4, I can't attest to any other model

Alesis Nitro Mesh

4x - 3.5mm Female jacks

9x - 3.5mm to 1/4” cable

8x - 2mm JST (?) plugs/jacks

For the pedal adapter

Update - After seeing some feedback and doing some more digging into using a reed switch, that's another option that's just as effective and a lot easier. Here's a great guide that covers that process, skip everything related to the Arduino and just use the reed switch creation. Credit to the creator!

https://www.instructables.com/DIY-Custom-Rock-Band...

Arduino pedal only parts

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1. 1x Arduino pro mini - Or other Arduino board, I chose this one because it runs at 3v (the same as the drum kit brain), is small, and cheap. You can find off brand ones for very cheap on eBay. Make sure it’s programmed in 3.3v/8mhz
2. 1x 1omh resister
3. 1x 1W Diode
4. Small circut board
5. Wire
6. USB Micro long enough to reach the Arduino (I'm using a 10ft USB extension cable)

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Tools

• Screwdrivers
• Wire cutter/stripper
• Soldering iron
• Heat shrink tubing
• Something to make a case - 3d printed or wooden box!

V1.1 Case - 11-2020

I've updated the case so it has more support and the dpad should work better out of the box. I added a matching 3d printed dpad back to compensate for the height differences between it and the buttons.

This case uses the back of the stock RB drum set where the inputs for cymbals, buttons, batteries, and the kick pedal are located. Be warned that getting the dpad working can be touchy, you may need to adjust how far you’re screwing the board in, but using the custom dpad back it should work close to perfectly.

I recommend printing this in PLA or PETG (my go to) with either the face down, which will result in a rougher texture on the front, or with it vertical standing on the top of the case. Either way with tree supports enabled in Cura, only touching the build plate.

Attached here are a version of the case with holes, without holes (drill your own), the dpad backer, and the Arduino code needed (copy the code within to the Arduino IDE).

Updated Files - 07-2021

I've included step files for both the case and dpad adapter. Please note these were some of the first things I created since touching SolidWorks in high school :-) I will hopefully have another update in the future but have not put more time into this version. If you make improvements please share!

The entire process won’t take long, in the end you’ll have a mostly assembled drum kit with a missing brain. Take off the legs and lay the main unit face down on the floor.

Unscrew the six screws holding the back panel on, put these aside and keep track of them.

Pull off the back, it may take a little bit of effort but make sure not to pull it too far out. Flip the entire panel over and remove the connectors shown, then unscrew the board itself. Put these screws aside as well.

When taking these connectors out, pull directly up on the connector. I pulled out the socket with a few of them which didn’t cause any damage. If you do just pull them off the wire and press it back onto the board. Make sure you’re orienting it correctly, all of the notched sides face the center of the board

At this point the buttons are going to fall out. You should have (on the Xbox version) the select and start buttons, main Xbox button, A/B/X/Y. You’ll also need to unscrew the bracket holding the dpad in, remove the two screws and pull both pieces apart.

At this point you have everything you need, tuck the cables still attached to the drum somewhere and put it in storage.

3.5mm jacks - Cut the wire so it’s around 10-12” from the end with the jack, then strip 1-2" inches to expose the wires, making sure not to cut too much of the outer copper wire. You can get rid of everything that came with the kit listed in the parts section except for this. Practice stripping the wire on one of the longer scrap pieces!

5x 3.5mm to 1/4” cable - Put these aside, they’re good to go. These will be used for the main snare, toms, and pedal.

3x 3.5mm to 1/4” cable - For the cymbals we need to reverse the polarity of the cable.

Cut them, strip and cross the white/red wires, solder them, then seal everything up. Connect the copper outer wires too (not shown in this picture). I used tight pieces of heat shrink for the individual wires, then another sleeve over everything. You can also use this process to shorten the wires if you would like to.

On the jacks I bought the paired wires from the jack (red and white) are soldered together and hooked up to the up to the red 2mm plug wire, and the outer copper wire is connected to the black 2mm plug wire. Wrap everything with heat shrink tubing to make sure it won’t short.

Do this for all four of the jacks. After making one, I would connect it to the brain and test your drums before you finish the rest.

Start by putting the dpad and other buttons into the case, keep an eye on them as they will happily jump out as you’re working. Use the 3d printed dpad backer and put the stock one somewhere safe.

Then put the main brain board in and screw it in using the four screws from before, make sure to align the button pads with the buttons. With the current case, push the buttons a few times as you tighten the screws until you reach a point where they all feel right. Put the four 3.5mm jacks into the case, it’s going to require a bit of tucking and squeezing.

Connect the 2mm jack to the four snare/tom ports, identified in the picture below. I labeled each jack and connected them in the iconic red, yellow, blue, green order.

You’ll also want to unplug the wire connected to “E8” (orange), this is the drum pedal jack we’ll route through the Arduino.

Reed switch

https://www.instructables.com/DIY-Custom-Rock-Band...

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I didn’t plan on needing an Arduino so its placing is “wherever it’ll fit”. The good news is it’s a super simple circuit that I pulled from the Arduino knock sensor sample. Please note in the pictures I used randomly colored wires, sorry! I used dupont wires since I'm still tinkering on it, I would solder the wires directly to the Arduino.

This monitors the Alesis kick pedal piezo and when a hit is detected, simulates the stock kick pedal switch being closed for a short period.

• Connect the Arduino's analog in (A0) to the piezo,
  • A resister and diode is added to protect the Arduino
  • Look at the photo to make sure you're orientating the jack correctly (the program I used for the diagram didn't have anything that represented the JST connector perfectly)
• Connect the digital out pin (9 or D9) to the red wire of a JST plug
  • This goes in the socket that corresponds to the kick pedal
• Connect a ground from the Arduino to the negative terminal of the battery pack

If you’re cramming everything to the case like I did, put a piece of electrical tape on the back of the circuit board.

I’m not going to walk through programming the board but it’s fairly simple and should take you an hour or two if you’re doing it from scratch. Make sure you’re programming it in 3.3v/8mhz, the script settings are made for 8mhz.

This is a great Sparkfun guide on programming the board, it should be the same for any of the generic pro micro boards you’ll find out there.

Hoping in V2 to share the same batteries as the main board or at least get rid of the need for a USB cable. I printed this case and used the bottom half to tuck the boards in.

Route the Arduino’s power connector in through the side hole. Tuck everything in, being careful not to pinch, crush, or unplug anything. I found that the Arduino case I used nestles nicely in the spot shown in the picture. Use four of the screws you put aside earlier to fasten the back on, in the V1 case that’s the top and bottom two sets of holes.

Cable organizers

Feet for set - I mounted mine to a 2’x4’ piece of particle board

Cymbal screws - My goal is to print one for each of the three colors

The case is designed to fit right into a normal Alesis drum brain mounting bracket. Connect all the drums, cymbals, and kick pedal, then plug in the USB power for the Arduino. You are ready to rock!

If you find that the drum pedal isn’t as responsive or is double registering, try modifying the hit threshold and wait period in increments of 25.

Thanks for reading this far, if you've followed this guide let me know any improvements you make to the process!