Music player: Finalising the hardware

I'd tested out my breadboard prototype of the whole music player, and everything worked well. So I needed to do some final soldering to make the connections more permanent.

I didn't want to solder directly onto the Pi and I wanted the other components to be easy to remove in the event I wanted to make any changes to the setup of the hardware.

Making the connectors

I opted to use some of the breadboard jumpers I already had along with some AdaFriut Pig-Tail cables to make the pluggable wires I needed.

The power cable to the Raspberry Pi needed to be stable so it didn't come loose, to make this, I decided to use three female breadboard jumper connectors to make a three-pin connector. Only the first and third pin actually needed wires, the middle pin is just for stability.

Three breadboard jumper connectors

I super-glued the three connectors together to make one, more stable connector, and plugged it into some spare headers to allow it to dry.

The glued power connector

I also needed a two-pin power connection from the PowerBoost to the amplifier. For this I used one of the pig-tail connectors, and soldered this directly to the output USB connections on the PowerBoost so this could plug into the amplifier.

The PowerBoost and pig-tail cable

I needed a better way to connect the audio pig-tail cable to the amplifier. The audio cable connects to four pins on the amplifier board, so for this I created a four-pin cable, soldering the inner two pins to the ground of the audio cable, and the outer two pins separately to the L and R connections of the audio cable.

Soldering the audio cable

Raspberry Pi model A+

I decided to pick up a new Raspberry Pi model A+. I'd previously looked into the power consumption on the different models, and since I only had the old original B model I knew I could reduce the power consumption a reasonable amount by simply swapping to the model A+.

Since the model A+ doesn't have a network connection, and the project was intended to be wireless anyway, I ordered one of the official Raspberry Pi WiFi dongles. I know smaller dongles are available, but I selected this one hoping the larger size would give better WiFi reception. The physical size of the project wasn't my main concern, and since the official dongles are a good price and I know they are fully compatible, it seemed like a good option.

Raspberry Pi model B and model A+ (with WiFi dongle) side-by-side

I knew the model A+ would be smaller than the model B, but seeing the two side-by-side, it's still impressive to see how small these devices are.

Putting it all together

So with all the pieces built, I put the project back together without the breadboard.

Completed hardware. Battery disconnected

I plan to look into which software I want to use with the music player properly later on. I know there are a number of options available, but for now I'm using a basic install of Pi MusicBox.
Since this is easy to set up out of the box and the configuration can be done by changing a few settings in a text file on the SD card before you put it into the Pi, this seemed an easy way to get the WiFi working and music playing with minimal effort.

The completed project, playing music

The PiMusicBox software supports playing of music via multiple methods, but I tested it out with some music playing from an iPod over AirPlay.

For now, I am using a simple SPDT slide switch to control the power on and off, but I am working on a better solution for when the music player is installed into a case.

So that's the main soldering and circuit completed. Next, I plan to build the circuit into a suitable case.