This is a Rectify Series drop-in speaker system for Atlas Classic & early-run Master U30/33/36C locomotives. The speaker is a beautiful press-fit between the rear weight and motor mount. No frame/weight/shell modifications are needed! The factory PCB will need to be removed with either a Decoder Buddy installation or a hardwired decoder.


The speaker comes fully assembled and tested.

Atlas Classic/Master (early) U30/33/36C