Tag: arduino

I was contacted by someone who really liked the Four Button MIDI Box I had built but was hoping for a less expensive version, so I built one. The Four Button MIDI Box had some specific design requirements regarding size and power, which made it more expensive, but this version (dubbed “LC” for “Low Cost”) does not have such constraints, uses a different source of power, and different components.

This one actually gets power via Micro USB, so any old cheap phone charger should work just fine. Also, while this specific one only does MIDI out via the 5 Pin DIN port, it is capable of doing MIDI out via USB as well. In fact, it can send different data out of the DIN port and the USB port if desired, which is kind of cool.

I usually start these kinds of projects doing some simple sketches to get an idea of size & scale of things. Once the customer and I agree on things I do a 3D model of the enclosure so it can be 3D printed.

It usually take between two and three prints to get it perfect. Sometimes I just do partial prints of certain parts (like the holes for the jacks) to make sure it’s all good. This time I did the math wrong so I did three prints to get things perfect. (I also printed a spare right away in case it was needed.)

I’m pretty happy about how this one turned out. Leaving a bit more room for wiring inside the enclosure really helps. I also used silicone wiring which is more flexible and easy to shove into place. In fact, I may build another one right away and add it to the shop in case someone else wants one.

A musician got in touch with me about building a custom MIDI controller. This one works in conjunction with a Roland TM-2 Trigger Module. The way the TM-2 works is that it has two physical trigger buttons, but you can use two more by pressing a “shift” button so you get a total of four buttons. He said this worked fine for recording, but was not great for a live setup, so wanted a device with four physical buttons to press. He was looking for something about 2″ by 4″ in size.

I asked if he wanted all four buttons in a row, or two rows of two buttons, and we went with the latter. He also wanted buttons closer to 20mm rather than 30mm in diameter so that meant standard arcade style buttons would not work. I found some nice (metal) push buttons thar were solid so we went with those.

Here’s the 2D sketch I provided to the client. These sketches also help me determine the dimensions of the final unit. I basically create these sketches at actual size so I can determine spacing of all of the components. I also use the sketches to get approval from the client.

Like the Handheld 5 Button MIDI Controller we decided to go with a 3D printed enclosure rather than track down an existing metal or plastic enclosure that was the required dimensions.

The one difference from the 2D sketch is that the power LED got moved to the opposite corner just to allow more spacing between components. Speaking of spacing, I do wish I had made this enclosure just a wee bit larger, as stuffing all of the components and wires in was a bit tricky.

Somehow I managed to not take a photo of the power plugged in, but it goes into the smaller socket to the right of the MIDI jack. The LED turns on when power is plugged in.

This was another fun project and I learned a few things in the process. Hopefully the group using this (who makes music described as a “euphoric collision of post-punk, trance, and deconstructed opera”) finds this controller to be useful in their live shows.

Here’s another recent build. A five button handheld MIDI controller. This one is not USB MIDI but has a 5 pin DIN MIDI connector to go directly to an instrument. (This one will control a BOSS RC-505 Looper.) A musician got in touch with me about this, asking for a “small detonator style device” and that’s what we designed and built.

I’ll do a quick walk-through of the process for this project with some notes and illustrations.

This was the sketch the client sent, so I could get some idea of what they had in mind. My first question was about the dimensions of the unit, since finding an enclosure would probably be the largest challenge for the project.

Here’s the second client sketch showing dimensions. (You’ll also notice six buttons, though we knocked it down to just five for this iteration.) With the dimensions in hand I started looking for enclosures. Metal would have been preferable, but plastic would be acceptable.

Sadly I did not find any good enclosures the desired size, so I suggested using a 3D printed enclosure so we could make it custom and the exact size we needed. The client agreed to that and I started designing.

Here’s my first design sketch. It’s got some transparency because I often want to see how things fit inside the enclosure to ensure we’ve got enough space for everything. This one shows a rocker style power switch on the top.

A quick change moving the power switch to the side of the unit instead of the top, per the client’s request. This increased the length of the unit a bit.

Here’s the final sketch for the device. We switched to a power button with a built-in LED so it could also serve as a power indicator since this is battery powered. This sketch got final approval which meant I could start designing the 3D model and putting together the electronics.

Since durability was important the walls for this enclosure are 4mm wide and the infill is at 30%. The print came out great. I printed it on an upgraded Creality Ender 3 with black Hatchbox filament.

I was really pleased with how this came out. Rather than design a battery compartment I used an off-the-shelf battery holder for an electric guitar, which I think worked well.

This project took a lot of time, but it was a fun challenge, and it feels good to be able to help a musician expand their performance capabilities.