[Experiment 1] Sound hole size

The Structure of the Acoustic Guitar

Performing a sound experiment

What effect does the size of the sound hole have on the sound? We compared the sound as we changed the size of the hole.

Experiment steps

1. Create a lidless wooden box.

2. Create a lid from a urethane board.

3. Use a circular cutter to cut duplicate holes, then glue to the wooden box.

4. Attach offcuts and fasteners and install a string.

5. Change the size of the hole and compare the sound of the string.

14 cm diameter

6 cm diameter

No hole

* As this was an experiment, the recorded pitches differed from the correct notes.

We used string 1 from a guitar. The larger the sound hole the louder the volume grew; conversely, the smaller the sound hole the quieter the volume became. However, smaller holes produced a mellower sound. With no hole you only hear the sound of the string itself, so the sound was weaker and quieter.