Just read on the Spur-G Blog that ZIMO started delivering a special decoder intended for Aristo and Bachmann engines. Supposedly a PnP solution i.e. the pins match the sockets of the DCC interface.
It will be interesting to see how well this “fits”.
The sound decoder comes in two versions: MX697S (standard version) and MX697V (version with onboard 5V circuitry for the servos.
German language quick review. http://www.spur-g-blog.de/?p=15495
Link to the ZIMO sound file database http://www.zimo.at/web2010/sound/tableindex.htm Again in German but easy enough to decipher just scroll down to the US section.