Marklin sound decoder MSD3. Clip/modifies Marklin/Trix H0 hobby locomotives of the 36 Series. The Marklin sound DECODER3 is equipped with a 21 pin interface complimented by an interface board for swivel frame locomotives of the 36 Series. The Marklin DECODER3 supports the digital file formats MFX sound, mm 1 mm² and dcc. default sound a electric engine (Traxx).