So far it has all been digitraxx.    I went out and joined the yahoo group.  Lots of things there to read and learn.  Thanks for the pointer to this group.   Still thinking about what direction to go.   You guys are the best.

Fred you are making the digitrax sound better and better.   

Thanks for the reply.  I have access to a computer (laptop) and could program  (IT person in a former life) I have read that the Vandy tender is tight but from what I have read  either will fit.   $60 is a lot of money these days. 

Just bought my second Spec Backmann steam engine. This one is a  Heavy Mountain.  I want to add sound to it.  It comes with a Vandy tender.  I could use the soundtraxx 750 or the digtrax SDN144PS.  Being retired and on a fixed income i have to watch my funds given the cost diff between the two.   However I will listen to advice from folks who have done this before.  Open to suggestions.

By the way will a vandy tender for a H4 2-6-6-2 work with the light mountain or the heavy?