Let There Be Sound

I found a MRC sound decoder for a good price, so I picked it up for my Bachmann J class. I really wanted to put sound in at least one of them because I really liked the sound in my K4.

I am underwhelmed.

First, the MRC doesn't have the right bell or whistle for the J class, which turned out to be a relatively minor thing overall.

Second, getting the chuffs to start when the locomotive does instead of having it sound like it's moving when it isn't was not an easy thing to do, compounded by the fact that the motor control for MRC isn't the same as the Digitrax, or so you are led to believe from the MRC instructions. MRC uses 32 steps from 0-32 instead of 0-255 like the Digitrax. I managed to get it right though, by using the 0-255 settings instead of 0-32, but then that led to the next problem.

Synching the chuffs up with the wheel movement is not going to be possible because they really need to have one more chuff rate past what is programmable. Not only that, but when the loco slows down due to hills or curves the chuffs do not. On the K4 the decoder uses motor BEMF (back electro-motive force) to control the chuff rate, but the MRC does not. That means the MRC decoder has no way of knowing when the locomotives electric motor is being bogged down, so it has no way of controlling the chuff rate.

Next, the noise control keys are different between the MRC and the Soundtraxx in the K4, so the key that is used to turn the steam release petcocks on for the K4, for instance, is different from the J class. Fortunately the headlight control, whistle and bells are still the same so the hard keys on my NCE PowerCab for these functions still work like they should. I suppose if I was more DCC savvy I could re-map those functions.

Last but not least, getting the decoder itself to fit into the tender required that parts of the tender be cut out. I got it to fit, but as a result one of the screws that hold the tender shell in place had to be eliminated. It does fit and it is staying in place, but I really don't like the fact that there is only one screw holding it on now.

It's not all bad, there are some sounds in the MRC that are not available on the K4 (at least not that I've found). I don't know that I will use couplers clanking or a conductor saying "All Aboard!" but it is there if I want to.

Eventually I think this decoder will find its way into another locomotive (perhaps a Minitrix K4) and I will end up getting some Soundtraxx decoders for the J class since that is what Bachmann uses for them. Hopefully they will use the motor BEMF to control the chuff rate. Fortunately for me (not that I planned it that way but this is the way it worked) I did not cut the wires off short, so it can be used elsewhere.

It would really be nice if I could buy the J class tender with a sound decoder already installed, but unfortunately that is not an option, at least not yet.