tabletop metallophone for gamelan practice \\ prototype 2 (build guide)

article 1; prototype 2.

So I’ve been thinking about how to source accessible and affordable (like, instant ramen student budget affordable) practice instruments for the study of Balinese gamelan music.

At the time of writing, I have prototyped two (very ugly) metallophones, each clocking in at around the $40-60 AUD mark for parts and materials (it turns out that music is expensive), and less than 10 hours to build from scratch (speed and budget are important since I plan to make instruments for the players in UNSW’s community gamelan Suwitra Jaya). Though there’s a fair way to go, I figure it’s about time to reflect on what I’ve picked up so far.

Honestly, it’s probably worth spending a little more for stainless steel.

Design considerations below, or skip ahead to the build guide.


To look at, Balinese metallophones are relatively simple, really consisting of only six components:

  1. Frame, beautifully carved
  2. Keys, domed and slightly raised in the centre
  3. Resonator tubes
  4. Cord/string (used to mount keys on mounting hardware)
  5. Short bamboo dowels (used to mount keys on the cord)
  6. Mounting hardware (brass hooks and slotted tabs between pairs of keys)

So this should be easy, right? Well, nearly all of the parts used in Balinese instruments are things you can’t easily DIY or buy online – even before 2019. So we’re either going to make some substitutions or be prepared to fork out the big bucks for tools and raw materials.

design considerations

Now might be a good time to think about what the instrument will be used for:

  1. Instrument is for home practice and memorisation purposes, so it doesn’t need to sound particularly great or be especially loud. Therefore:
    • resonating pipes are not required (and in turn, the frame can be much shallower and lighter)
  2. Affordability, accessibility of materials, and ease of construction are of utmost importance, therefore:
    • traditional mounting hardware can be swapped out for one that uses finished components readily found in hardware stores.
    • Cast brass keys can be swapped out for standard flat constructions bars (readily available in aluminium and various types of steel)
  3. Portability & ease of storage are highly desirable, therefore:
    • The traditional standing frame can be swapped out for a simple slim design which can be placed on a table top.
    • Keys can be made from thin material to reduce weight and strain on mounting hardware.

Well, you can see where this is going. So after two prototype tabletop metallophones, here are some things I’ve learned:

  • Expect to spend $60AUD on materials alone. For such an ugly DIY instrument, it’s a remarkably expensive project.
  • Plain steel sounds way better than aluminium. Much stronger fundamental partial tone – and it’s cheaper!
  • Buy the thickest flat bars you can afford for the keys; I’ve found 3mm steel is too light and feels weird to play on. (Note that thin bars resonate at a lower pitch than thick bars of identical length, width and density. This means you’ll have to build a larger frame if you use thicker material). For comparison, pemade and ugal keys in the set used by Suwitra Jaya regularly measure in excess of 50mm wide and 10mm thick, and the highest pitched keys of the kantil can easily hit 20mm in thickness.
  • 32mm-wide flat bars are very narrow by gangsa instrument measures.
  • 40mm is too high for the timber frame – looks weird. 30mm is plenty, 25mm is even better if you use a strong hardwood.
  • Developing an appropriate Balinese-style mounting system becomes a very real issue in extremely low-budget tabletop metallophones. Lightweight keys like to bounce around, and a hard hit can easily kick the cord out of the mounting hardware unless it’s fixed in place – but the more things you fix in place, the more awkward it becomes to make repairs as parts wear out.
  • Make instruments in pairs, and then give the second one to a friend. It’s more cost-effective and more fun!

Flip over to the next page for the build guide!