A tiny speaker board for adding sound to projects
Pimoroni’s latest pHAT may not sound all that phat, but it does offer a neat way to quickly add audio to your projects. This Pi Zero-sized board manages to cram in a mini speaker, I2S DAC, and mono amplifier. We particularly appreciate the 1980s boombox-style artwork on the top of the board, complete with a ten‑LED bar graph.
The full article can be found in The MagPi 55 and was written by Phil King.
Since the 8Ω speaker has just 2W of power, you won’t exactly be rocking the neighbourhood. It sounds more like a tinny transistor radio than a ghetto blaster, offering little in the way of bass (and obviously no stereo), so it’s certainly no rival for high-quality audio add-ons from the likes of IQaudIO and JustBoom. But then that’s not what it’s intended for; instead, it should prove suitable for projects that require audio output for notification sounds or speech. Indeed, it would be ideal for the digital whoopee cushion in this issue, precluding the need to wire up a separate powered speaker. Other use cases include a retro gaming handheld or – by pairing it with a mini microphone – a DIY voice assistant based on Amazon Alex or the like.
The Speaker pHAT comes in kit form, requiring about 30 minutes to assemble. First, you need to screw the speaker to the rear of the board, using tiny spacer nuts, which is a little fiddly. Then it’s time to get the soldering iron out. Soldering the speaker’s two terminals to the board contacts with the supplied 24AWG wire is a bit awkward and you need to use tweezers to hold the bare wire as it gets hot! It’s then simply a matter of soldering on the 40-pin female header and the pHAT is ready to use.
Installation of the software is achieved with a single terminal command. It should then work as the default audio output, although you may need to reboot the Pi first. We tested it out with aplay and mplayer from the command line, as well as Sonic Pi and YouTube in the Chromium web browser. There’s also a library for manually controlling the LEDs if you want.
Not one for audiophiles, the Speaker pHAT offers rudimentary sound quality with little power. It is nevertheless a great way of adding audio to projects, with its tiny Zero-size footprint and no need for a separate power supply. It looks cute too.