As regular readers will know, here at Hackaday we are great enthusiasts for the PCB as an art form. On a special level of their own in that arena are the Boldport kits from [Saar Drimer], superlative objets d’art that are beautifully presented and a joy to build.

The trouble some people find with some of their Boldport kits though is that they are just too good. What can you do with them, when getting too busy with hacking them would despoil their beauty? [Paul Gallagher] has the answer in one case, he’s used not one kit but two of them as for a guitar tuner project.

At its heart is a Boldport Cuttlefish ATmega328 development board, and for its display it uses a Cordwood Puzzle as an LED array. All the details are available on a GitHub page, and it’s a modified version of an Arduino guitar tuner he found on Instructables. In particular he’s using a different pre-amp for an electret microphone, and a low-pass filter with a 723Hz cut-off to reduce harmonic content that was confusing the Arduino’s algorithm.

The result is a simple-to-use device with an LED for each string of his guitar, which you can see in the very short YouTube clip below. It joins many other tuners we’ve featured over the years, of which just one is this ATmega168-powered project with MIDI-out.