Back surdo (L for low, H for high) R/L: accented note (right/left hand suggested) r/l: quieter note * : trill, generally three very fast notes on repique/caixa, two or three for surdos Add schematic, start on PCB choices could also do all-different colors, but unfortunately Mouser only has A1Ms in orange. Expensive, about $3 each. Replacing LEDs in many places might be more stable than MK's, but it's unclear what that means and whether it is safe to put the output to allow.