What is the recommended add-in sound decoders for the DDA40X (Bachmann mislabled them as DD40AX) diesle locos. I have 2 of them, both DCC Onboard. They have 2 motors according to the exploded view of the insides and I haven't opened them up yet so don't know how much room there is.
there is space for a speaker provided in the fuel tank, replace stock motor decoder with a sound decoder via 8 pin socket, brand choice is up to you, soundtraxx and QSI, both have a DDA40X sound sets for their decoders, for other brands, use a GP/SD40 sound decoder.
(http://i46.photobucket.com/albums/f123/river_eagle/HO-Scale/dda40x018.jpg)
(http://i46.photobucket.com/albums/f123/river_eagle/HO-Scale/dda40x022.jpg)
(http://i46.photobucket.com/albums/f123/river_eagle/HO-Scale/dda40x025.jpg)
(http://i46.photobucket.com/albums/f123/river_eagle/HO-Scale/dda40x021.jpg)
(http://i46.photobucket.com/albums/f123/river_eagle/HO-Scale/dda40x024.jpg)
The Tsunami is capable of dual prime mover sound. Go to the below link and do a lot of reading. Don't know your level of DCC experience.
http://www.mrdccu.com/curriculum/soundtraxx/tsunami.htm
Rich
The new QSI Titan decoder has stereo output/speakers for the dual motor setups
http://qsisolutions.com/news/11/qsi-titan-intro-030811.html (http://qsisolutions.com/news/11/qsi-titan-intro-030811.html)