1.5 – Shopping List (BOM)

“Show me the money!”

You’ll need a few things to fulfill your lifetime dream of building and giving away your own Marta Musik Maschine.

Before ordering anything, make sure that all the prerequisites are met for this project. Definitely read through every single blog post so that you know what’s coming up to you. It’s important to have a few things at hand and a certain set of skills if you want to successfully conduct the task of building M³ the way it is intended:

  • 3D printer (minimum print volume: 18cm x 14cm x 6cm)
  • Basic soldering experience and corresponding tools (soldering iron, tin-solder, maybe helping hands or PCB holder)
  • Tools (screwdriver, tweezers)
  • Computer (micro SD card reader, connection to WIFI devices)
  • Basic knowledge of the Linux command line
  • Ability to help yourself or find answers by investigating problems

After you’ve convinced yourself of your skills and even have the devices available, here’s the things we’ll need later that I’m almost 100% sure you do not have at hand.

itemprice / shipping / lotprice / needed
Marta Musik Maschine PCB24.18€ / – / 201.21€ / 1
Raspberry Pi Zero W10.53€ / 3.50€ / 1 14.03€ / 1
On/Off Shim7.25€ / – / 17.25€ / 1
5W 8Ω Speakers5.63€ / – / 25.63€ / 2
WS2812B 60IP67 LED strip5.81€ / – / 1m2.90€ / 0.5m
74HCT245 bus transceiver1.37€ / 0.77€ / 50.43€ / 1
MPU6050 6 Axis Sensor0.49€ / 0.62€ / 11.11€ / 1
PCM5102 Decoder2.47€ / 0.80€ / 13,27€ / 1
PAM8406 Amplifier0.48€ / 0.58€ / 11,06€ / 1
24mm Arcade Push Buttons8.49€ / – / 122.83€ / 4
RDM6300 RFID Reader1.95€ / – / 11.95€ / 1
125kHz RFID tags1.86€ / – / 101.86€ / 10 (?)
0.2m Micro USB Cable M to F Left1.23€ / – / 11.23€ / 1
10Ah Intenso Powerbank 733253012.99€ / – / 112.99€ / 1
M3 60mm screws2.49€ / 1.50€ / 200.80€ / 4
Sum91,80€58.55€

I have to admit: I do not like that price tag at all.

There are at least four ways to make the whole setup cheaper.

  1. One could use a Pi Zero instead of the Pi Zero W. We’d lose all wireless capabilities and had to use a cable connection to push new music to the device but at the same time save about 5€. I thought this was not worth it.
  2. I find the On/Off Shim too expensive. I really wonder if there are any other alternatives available that I missed.
  3. Sometimes shipping costs exceed the item’s price because we order a single unit. As soon as you buy a handful of the same component, relative shipping costs drop rapidly.
  4. If you do not want to print the enclosure, but build your own one and only use the electronics and software, you could use cheaper electronic components (battery, buttons, loudspeakers, maybe even leave out the ON/OFF Shim).

I guess that most enthusiastic nerds have many of the following commonly used electronic stuff lying around. If that’s not the case, you might want to get them.

itemprice / shipping / lotprice / needed
16 GB Micro SD Card4.69€ / – / 14.69€ / 1
2 Pin JST XH2.54 XH0.71€ / – / 100.71€ / 10
status LEDs1.15€ / – / 1000.02€ / 2
resistors2.50€ / – / 6000.02€ / 4
shrink tubing1.50€ / – / 1640.18€ / ~20
5m 24AWG wire0.91€ / – / 5m0.09€ / 0.5m
6mm DIP button0.78€ / – / 1000.01€ / 1
7mm thread button0.92€ / – / 50.18€ / 1
male pin headers1.37€ / – / 300.14€ / ~3
M2 M3 screws/washers/nuts4.56€ / – / 1600.57€ / ~20
super glue1.73€ / – / 50.17€ / ~0.5