Smartphone Amplifier

These stylish amplifiers not only boost volume but can also improve the sound quality of your phone's built-in speaker.

- Charles Mak

PROJECT #2412

Skill Level:

Beginner

Time: 2 Days

Cost: $5

Plastic smartphone amplifiers can be had for about $15 a piece, but expect to fork out $100 or even more for a fancy handcrafted wooden one. They give a louder and richer sound than the phones by themselves. In a nutshell, they are just a box with a front opening and with a slot on the top to accept the phone. I made mine out of poplar and plywood scraps. In this article, I will show you a well-thought-out process that guides you through the making of a large batch of amplifiers in as few as two shop days. With literally everyone-young and old-owning a cell phone nowadays, these amplifiers could well be one of the most popular gifts you ever make.

1 The speaker can also do double-duty as a coaster.

Create the Design

Phone amplifiers can be made in all kinds of shapes and sizes, but a trumpet-shaped cavity will give the best amplifying results. I prefer a more compact design and the whole box measures 13/4" x 41/2" x 5". For a more stylish look, I designed the box to be in a speaker shape instead of a square or rectangle, as commonly seen. While primarily an amplifier, I also use it as a cup stand in the shop. You can add any other desirable features to your design, such as making it a charging station as well.

Given the angled shape of the amplifier, it would be quite a challenge to build it with any traditional joinery such as a dovetail or butt joint. My solution was simple and easy to execute: first, I laminated three pieces to form a rectangular box with a hollow chamfer (refer to page 31). Then, I cut the box into its final shape.

2 Align the left center point with the drill bit. Lock the stop block in place.

3 Drill the top and middle pieces together as a stack placed against the stop block.