Proto-Sound 2.0, a state-of-the-art digital sound system that can be operated in two different modes, Conventional Mode and Command Mode.

Conventional Mode: Conventional Mode consists of the collection of sound and operational features available right out of the box, as soon you put the locomotive on the track and fire up the transformer. In a conventional environment, the transformer controls the locomotive by varying the amount of current on the track. The more current on the track, the faster the engine will travel. Additional features, depending on whether the track is powered by an AC or DC transformer may also exist. With AC transformers, bells and whistles can be operated in conventional mode when transformers equipped with bell or whistle buttons are utilized. The bell and whistle buttons activate the appropriate sound in the locomotive by sending a DC pulse through the track's rails. The Proto-Sound 2.0 electronics sense this pulse as a "signal" to blow a whistle or ring a bell. However, because DC transformers output DC current on the track, the electronics within a Proto-Sound 2.0 engine cannot sense the additional DC pulse and are therefore unable to activate the bell or whistle/horn sounds effects. In short, if the operator desires to run a RailKing One-Gauge locomotive using a DC output transformer in Conventional mode, the only sound effects and operating features available are the following: steam chuffing or diesel engine sounds, squeaking brake sounds, air let-off sounds, direction control, speed control and synchronized puffing smoke.

Even operators who prefer conventional operation receive the benefits of Proto-Sound 2.0's improved features, which make for more realistic operation than other conventional locomotives. Best of all, M.T.H. engineered Proto-Sound 2.0 to be fully compatible with other manufacturers locomotives.

Proto-Sound 2.0 Conventional Operation Features (Accessible Through Any Compatible Transformer)

• Full Compatibility with Your Other Trains
  
• Proto-Speed Control
  
• Authentic Locomotive Sound Effects
  
• Directional, Constant Voltage Lighting including Steam Chuffing or Diesel Roar and Squeaking Brakes
  
• Built-in, Self-charging Battery Backup System
  
• ProtoSmoke Operation with Puffing Smoke in Steamers
• Works Under 50-60 Hertz Household Power

Command Mode: Command Mode allows operators individual command of multiple engines, track switches, and accessories at one time with a single remote. In command mode, Proto-Sound 2.0 engines include a host of additional features that allow them to behave more like the real prototypes than any other model trains. The primary difference between command and conventional modes involves track power management. Unlike conventional mode, track power is usually set at a constant voltage (around 18 volts). The locomotive will ignore the track current and will await a "command" from the control system to move at a specific speed or activate a particular function. Each command signal is sent to a specific engine so only one engine will respond to a particular command. The command signals are sent via radio waves or digital signals through the track's rails. You will find more information on Command Mode by clicking here.