The Westminster chime from my cuckoo clock. It works with a code for each note stored in a minecart chest. When activated, it swaps the minecarts and feeds the code through the hopper into the other minecart chests ready to repeat the whole process when it is done. The code is read with a comparator. If the comparator reads a stackable block, it gives a signal strength of 1 and does not play a note for that beat. If it reads a sword it gives a signal strength of 3 and it plays a note for that beat. The map download includes a spam proof doorbell version and a sunrise alarm clock version.