Okay, bad example - I was thinking that one of the DCC makers, maybe Tsunami, made a standalone sound decoder. Thinking more about it, I'm realizing it's probably not practical, since the DCC modules respond to DCC commands, not external triggers. Oh well.
GGG, I don't necessarily want to run conventional sounds in command mode, I was just wondering how to trigger another, higher fidelity sound source. The sounds on my PS1 gas turbine don't sound like the real thing IMO (sounds basically like a diesel), so I have no desire to keep them around. I don't know how accurate the PS2 sounds for that locomotive are, but the cost of the master and slave PS2 boards plus installation is prohibitive.
Fred