The Spectacle Audio Board allows you to add sound from a microSD card to your Spectacle projects. Each board accepts a microSD card with sounds in .ogg format, and has a 1/8" (3.5mm) audio jack line-level output ready to be amplified. It is important to know that the files used by the Spectacle Audio Board must be in OGG Vorbis format. This free codec has a higher compression ratio than MP3 and, more importantly, can be used without paying a licensing fee to any third-party organization. We use the free, open source program Audacity to convert from whatever the file’s current format is to OGG ..