The Multiphonic Duplicator is a duplication ray invented by Gyro Gearloose.
The Multiphonic Duplicator is a device invented by Gyro Gearloose that causes any object to replicate itself. However, as Gyro hadn't worked all the kinks out of the Multiphonic Duplicator yet, the duplicated items are highly unstable, duplicating themselves again every time any bell rings and eventually imploding back into the original item.
Unaware of its defects, Huey, Dewey and Louie Duck used the Multiphonic Duplicator on most of the objects in their bedroom, as well as on a silver dollar they had earned earlier that day. Fenton Crackshell later borrowed the Multiphonic Duplicator from them, seeing an opportunity to double Scrooge McDuck's fortune. Scrooge nixed the idea, partially on principle (Scrooge insists on working for every dollar he earns), and partially because it would cause enough inflation to ruin the economy.
Unfortunately, Huey, Dewey, and Louie's silver dollar had already duplicated itself a considerable number of times, and even worse, they had already spent some of the duplicated money. After being informed by Dr. Gearloose that the duplicated money should all implode soon (the objects in Gyro's shed he'd duplicated had already imploded), Fenton tricked the Beagle Boys into stealing all the duplicated money, so that it would all be gathered together someplace where the implosion wouldn't hurt anyone. Fenton then rang the doorbell on the Beagle Boys' new Money Bin, causing all the cash to implode into a single silver dollar (also restoring all the items in Huey, Dewey, and Louie's bedroom to their original number).
Behind the Scenes
The Multiphonic Duplicator first appeared in Dough Ray Me.