Martin Bläse Planetary Tuned Sound PlatesThis listing comes with the plate only. Martin Blse Planetary Tuned Sound Plates are a phenomenon. "For the first time, I have instruments whose sound is so loud, pure and so far in the open, that they can be played without difficulty even outside of closed rooms." says Martin. Depending on the model, size and velocity, the plates can ring for up to six minutes. Metal idiophones such as bells, singing bowls, and gongs naturally have many overtones,