Guitars are usually made of wood. Whether it’s an acoustic guitar with a large open cavity, or a solid-body electric, there is generally a lot of wood used in its construction. However, [Mattias Krantz] shows us that alternative construction methods are quite possible, by building his own balloon guitar.
The balloon guitar still has a neck, bridge and strings just like any other. However, instead of the resonant cavity of an acoustic guitar, there is provision for installing a large balloon instead. It’s actually quite interesting to look at – with the balloon installed, the guitar delivers a lot more volume than when played with no resonant cavity at all.
The guitar was actually built to test whether swapping air in the balloon for helium would shift the pitch of the sound. Of course, a guitar’s pitch comes from the tension on the vibrating strings, so changing the gas in the resonant cavity has no direct effect. Instead, much like inhaling helium to affect the human voice, the change is in the timbre of the sound, not the fundamental pitch itself. It sounds like the guitar has been given a subtle treble boost.
It’s a fun build and one that shows us that it’s possible to build musical instruments in many ways, not just using traditional techniques. However, if you want to play further with the sound of your guitar, consider turning to the world of machine learning.