Can you install a dcc decoder and sound in any brand of loco?
ho scale Model power , life like, athern, bachman have all
Electrically, yes, with varying degrees of difficulty. Many older engines used the metal frame as part of the electrical circuit. To install DCC, it's necessary to separate the motor from the frame electrically, which is referred to as "isolating" the motor. After that, it's just a matter of connecting some wires.
Some newer engines have sockets built in to accept decoders. In that case, it's really a piece of cake - just plug and play.
Sound decoders present an additional problem. For years, manufacturers have increased the pulling power of their engines by adding weight, so some engines have the shell almost completely full of metal. You can usually find room for a decoder, but a speaker is another matter. Squeezing one in may involve milling down some of that weight. This, of course, will be differerent for every engine.
Finally, there's the overall engine quality issue. The basic rule is that if an engine runs poorly on DC, it will run even worse on DCC. Athearn and Life-Like Proto engines are good quality, and will work if they're relatively new. Model Power and low-end Life-Like and Bachmann locomotives don't have such a good reputation, and may not perform very well after conversion. Bachmann Spectrum and some of their newer stuff is better quality, though.
If you have a good train shop in your area, take a couple of the engines in. My own LHS is happy to open up the engine and suggest mounting options for the speaker. For a fee, they'll even install it for you.
It takes an iron man to play with a toy iron horse.
NorthernwoodwCan you install a dcc decoder and sound in any brand of loco?
Some brands or series of locos are not worth installing dcc and/or sound into. The installation for each brand and type of loco is going to be pretty unique. There are lots of options depending on speaker placement and lighting features. It can be easy or hard, run really good or very poorly, and sound really nice or like junk. So in general there is not one answer to the question.