Building on that, there are pipe organs which are purely mechanical: cables or solid connections connect the keyboard to valves on pipes. There are newer ones w

Building on that, there are pipe organs which are purely mechanical: cables or solid connections connect the keyboard to valves on pipes. There are newer ones which use electronic contacts on key to signal electric-powered valves. I once owned a small organ like that. Some of the organs for sale online have rather short pipes - you don't get the full power of pipes 20 or more feet long.