The heyday of the Hi-Fi is lamentably behind us, with elaborate consoles that once took pride of place in the living room replaced by slim soundbars under TVs, or often obviated completely as tinny handheld devices become peoples’ only multimedia interface.

But if you want to add a VU meter or spectrum analyser (or both!) to your system, Mark “The Electronic Engineer” Donners has just the (Teensy-based, of course!) thing!

Mark’s solution consists of a custom PCB that houses a Teensy 4.1 (with PSRAM), our Audio Adaptor board, and dual ILI9341 displays.

Source audio can be via stereo line in, or an optional mono electret microphone. Gerbers and firmware are available on GitHub, with complete instructions on Instructables.