Exposing the Rock Band drum controller inputs

Overview

This is part 5 of the Using an electronic drum kit with Rock Band FAQ.

As we noted previously, the Rock Band drum controller contains a unique chip that identifies it as a drum controller to Rock Band.  Although it would be nice if we could connect our electronic drum kit directly to the XBox 360, we can't fake the presence of this chip.  So we will need to use the drum controller as an intermediary.

Rather than connecting the MSA-P directly to the Rock Band drum controller, we're going to wire up the inputs of the drum controller to a standard RJ-45 interface.  This will allow us to keep the pieces of this mod cleanly separated, and it will make it easy to rearrange/connect/disconnect the MSA-P and the Rock Band drum controller with a standard CAT-5 ethernet cable.  The various buttons/triggers of the Rock Band drum controller can then be triggered by the MSA-P over the cable.  Also, as a bonus, the drum controller is powered by the XBox 360 over USB, and that can also be used to power the MSA-P.

To destroy or not to destroy?

You will need to decide whether, in the process of doing this, you want to cannibalize the Rock Band drum kit completely or leave it operational and slightly modified.

Pros of cannibalizing the Rock Band drum kit

Just to clarify, this involves completely removing the center controller portion from the Rock Band drum kit and accessorizing your electronic drum kit with it.  You throw away the plastic drum stand and drums.

First of all, the Rock Band drum kit takes up a decent amount of room in addition to the electronic drum kit you just bought.  It's also highly unlikely you will want to play on the Rock Band drum kit at all once you finally get the electronic drum kit connected.  Why have the whole thing around taking up space?

Second, properly cutting out the center controller section of the Rock Band drum kit gives you the option of mounting the controller somewhere nice and stable on your electronic drum kit stand.  If you do this, you won't have to step over to the drum kit every time you need to do something that can't be controlled by the pads (aka speeding up and slowing down practice mode, mostly).

Also, it's slightly simpler to cut away the controller portion from the kit (less finesse required) than it is to mount a port or extrude a cable from the overall kit.

Pros of NOT cannibalizing the Rock Band drum kit

Read more about k1ds3ns4t10n's modified kit.

You can always cut away the controller portion later after everything is verified as working.

You may feel safer during the whole modification process.  Most likely you'll still have a working Rock Band drum kit if something goes wrong, short of catastrophic damage to the drum kit controller board during the whole process.

You can practice on the Rock Band drum kit occasionally if you want to be able to play the game well when visiting friends.

Leaving the Rock Band drum kit operational might be good for guests or for kids you don't want touching your expensive electronic drum kit.

What I did 

Initially, I decided to just wire up the Rock Band drum kit, but leave it intact.  This seemed like a safe approach if things went wrong.

I cut a hole near the rear of the drum kit and put my CAT-5 cable through the hole after soldering in the connections.  Then I put an RJ-45 coupler on the cable …and voila, an RJ-45 port was hanging out of the drum kit that I could plug the MSA-P into.  This wasn't really as clean as mounting a port directly into the drum kit, but I didn't have the parts handy at the time.

However, after a couple of weeks, I felt that the Rock Band drum kit was just getting in the way.  So I opted to just go ahead and cut away the controller section from the rest of the plastic drums, as you saw in an earlier picture.  Plus with new drum kits now being sold in stores, I felt if something actually went wrong I could replace the drum kit very easily and quickly.

This has been great and I don't regret doing it.  However, I haven't yet gotten the parts I need to mount the controller to my Roland drum stand, so the controller is just sitting next to my drum throne for use when I need it.

Modding instructions

Exposing the controller board

Unscrew the three screws on the center underside of the Rock Band drum kit.  The following picture shows the screw holes that secure the plate.

Remove the plate secured by the screws and set it aside.  You should see something similar to the following…minus all the wires … this picture of someone's controller, post modification:

If you see a four wired USB connection, gently remove it from its jack so that it isn't in the way when you start soldering.

Getting the wires ready 

If you have decided to keep your kit intact, then measure out approximately 18 inches of CAT-5 cable and make a cut.  One end should be an RJ-45 connector, and the other should be cut and exposed wires from the middle of the cable that we will solder to the controller.  You need the extra inches so that the cable can extend out the front of your drum kit.  If you are not intent on keeping your kit intact, however, or if you want to just route the cable out the bottom of your drum kit (more on that later in the article) then you may consider cutting as little as 5-6 inches.  A longer length of wire will just get in the way and make the controller less self-contained.

Using some scissors, cut away about two inches of sheathing from the exposed end of the CAT-5 cable.  This will allow you to expose the eight wires inside the CAT 5 cable.  Untwist/separate each pair of wiring.

Now, strip about one cm of insulation off the ends of each individual wire.  The wires are 24 AWG (this refers to the diameter of the wire) so use the 24 AWG setting on your wire stripper to remove the insulation for you.

Soldering – a quick introduction

The next step is to solder the wires to the board.  So here are some quick tips.

This should be painfully obvious, but the soldering iron is HOT.  Don't touch it or you WILL burn yourself.  Be very careful with resting it on its stand and don't leave it plugged in and unattended.

Plug in your soldering iron and give it up time to heat up.  It will take about five to ten minutes.  It will probably be good to have a folded up wet paper tow
el or sponge around so you can clean extra crud off the tip in between soldering jobs.

If you are using the soldering iron for the first time today, I recommend you "tin" the soldering tip…that is, coat the tip in a very thin layer of solder.  Simply cut two inches of solder from the roll, grab one end with your tweezers, and melt about half a cm from the other end onto the tip of the iron.  Wipe off any excess solder on the tip with the wet paper towel in a very quick motion by "pinching" the tip with the towel.

Before each solder, I recommend you also "tin" the exposed wire.  Each individual wire is actually made up of about 8 copper strands.  First, just twist them up lightly with your finger to keep the strands together.  Next, take your tweezers and grab the wire by the insulation a couple of cm before where the exposed wire begins..  Touch the soldering iron to the flat exposed tip of the wire.  Then touch the solder to wire and hold it in place until the solder heats and flows into the wire.  Again, about half a cm of solder will probably be sufficient.

Some gotchas.  Try not contact the solder with the soldering iron…the idea is to heat the wire itself to the point where the solder melts over it.  Second, the heat of the iron is likely to melt away a bit of the closest insulation on the wire.  Don't worry about that too much, it's not a big deal.  Third, you'll note that you need to grip the wire with your tweezers, apply the solder, and hold the soldering iron tip to the wire.  In a perfect world, you would have three hands to do this.  In a less perfect world, you can try holding the wire plus the solder with one hand and the iron with the other (this is what I did).  You can also get a friend to help you hold one of these pieces.  Or you can get a stable vise or clamp to hold one of the pieces in place for you.  Your choice.

Now, practically speaking, you might be able to get some melted solder on the tip of your iron to simply rub off onto the exposed wire.  This doesn't really work as well as you might think, tho…it tends not to stick or flow into the strands of copper as well as if you apply the solder properly.  Still, if you're feeling lazy, you can try it.

If you've tinned the wire properly, odds are that you won't need to apply extra solder to the connection itself.  This is good, because if you do need more solder, you're going to need to do some three handed soldering again.

Let's assume you have the wire properly tinned.  Simply bend the wire a little bit so that it's naturally "coming into" the connection at a good angle.  Next, grab the insulation of the wire with your tweezers a little bit above the exposed end of the wire.  Now…

1. Hold the tip of the wire to the connection point.

2. Quickly heat the connection (which should also have a bit of solder on it) with the soldering iron tip.

3. Let the tip of the wire melt/merge into the connection.

4. Remove the soldering iron tip from the connection.

5. Allow the connection to cool…this happens within a couple of seconds, but be steady with your hand for a few seconds or so.

6. Let go of the wire.  The wire should be secured to the connection now by the soldering you just did.  Examine the connection and verify that no extra solder has crossed over from the connection to other connection points.

If you've made a bad/weak/off center connection, then you can try to reheat the connection and make a better connection with the wire tip.  If you've somehow used too much solder, you can lift off extra solder with a braided cord or soldering pump as mentioned in the shopping list.

The points to solder

OK, now that I've explained how to solder each connection, you just need to go and do it a few times.  Each connection you make will allow that pad to be triggered by the MSA-P on the other side of the cable.

The ethernet cables I use are color coded according to the TIA/EIA 568-B standard.  See this link for reference.  From what I can gather, every ethernet cable is wired this way.

Here are the connections I suggest you make.  We will make equivalent connections on the MSA-P side using this color coding.

  • Orange/White or Light Orange – Red drum
  • Orange – Yellow drum
  • Green/White or Light Green – Blue drum
  • Blue – Green drum
  • Blue/White or Light Blue – Orange drum (aka the kick pedal)
  • Green – unused
  • Brown/White or Light Brown – 5V
  • Brown – Ground

For the XBOX 360 drum controller (green board):

Here's a diagram of where to solder the wires if you have the following controller layout.  Note that since I do not have this board, I can't tell which wire for the USB port will give you 5V.  You can identify the 5V connection by looking at jack when the USB cable is plugged in and seeing which one has the red wire.

Post-solder pictures (minus the 5V connection, because people didn't know you could use it for power at the time)

 

For the XBOX 360 drum controller (blue board):

  • Red drum – right side, 5th pin down.  Connect the Orange/White or Light Orange wire.
  • Yellow drum – right side, 7th pin down. Connect the Orange wire.
  • Blue drum – right side, 6th pin down. Connect the Green/White or Light Green wire.
  • Green drum – top side, right most pin. Connect the Blue wire.
  • Orange drum (aka kick pedal) – bottom side, 5th from the left. Next to an unconnected pin.  Connect the Blue/White or Light Blue wire.
  • 5V – top most wire on the rear of the USB jack.  It's exposed on the right side of the jack and is not visible in the picture.  If you examine the USB cable that plugs into the connector, the red wire of the USB cable plugs into here.  Connect the Brown/White or Light Brown wire.
  • Ground – Right most pin in the pair of solder points beneath the USB connector. Note that even though in the picture both solder points in the pair are glommed together, I would try to avoid doing that.  You only need to make a connection to the right most solder point.  Connect the Brown wire.

For the PS3 drum controller:

I don't have very precise details for this.  The best post so far is here.  But it doesn't make specific callouts for the color of drum to particular pins, nor does it try to USB power the MSA-P.

For the Wii:

Coming at some point.

 

Exposing the cable

OK, now you need to route that cable somewhere.  The Rock Band drum kit wasn't designed for us to make crazy modifications like this, so we n
eed to open up a hole somewhere so the cable can get out.

If you followed the shopping list, then the soldering iron you purchased also has a hot knife tip attachment.  This can be used to cut/melt through the plastic of the controller.  Don't worry, the plastic doesn't smoke up the place or anything.  It doesn't smell great or anything…I would still ventilate the working area well, but it's not nearly as bad as you might expect.

If you chose to cut the controller out of the kit, then this is really easy.  Just route the cable out of the controller section like so.

If you chose to keep your drum kit intact, then you have a few more decisions to make.

If you want this over with quickly, then just cut a small hole in the bottom of the controller section like Flash did and slide the cable out of that.

If you're feeling like a completionist, then you can use the knife attachment to cut a hole in the rear of the drum controller.  You will need to route the ethernet cable out of the controller section, through the inside of the drum and out the hole.  This will involve disassembling the kit further. (more to come)

The following pictures illustrate where I chose to cut the hole … in the yellow drum in an area with some space to work with.

 

If you are particularly adept and have the tools, you can mount an RJ-45 port directly into the controller where you might have opened up a simple hole, as you saw in k1ds3ns4t10n's modified kit.  In addition to looking cleaner, this has the advantage of placing strain on the jack instead of tearing out the cable if you accidentally trip on it.  Unfortunately I didn't do this, so I can't give you more details.

Wrap up

Close up your drum controller, plug it back into Rock Band and verify that each button on the controller still works.  If you opted to keep the drum kit intact, also verify that the pads still work.

You're basically done now…you should have a drum kit or controller that can be used with the MSA-P to control Rock Band.  Unfortunately, it will be a little difficult to test the connections on the other end of the cable without getting the MSA-P up and running.  But congratulations, this is the toughest part!

This entry was posted in Uncategorized and tagged . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s