Exactly, what produced the sound was pipes (and is, in a non-electrical or electronic organ) using the same air that feed the pipes by the bellows. It replaced

Exactly, what produced the sound was pipes (and is, in a non-electrical or electronic organ) using the same air that feed the pipes by the bellows. It replaced mechanical track action, keyboard coupling, register switching and even had memory to ‘remember’ a register presets or register sets.