Tom, you have one of the newer ones eh?, FANTASTIC!!!:thumb: , my Kato SD38-2 is made just as you described your SD40-2, you are really in for a treat, installing a sound decoder in those is a snap:winki::mrgreen: , VERY EASY...easier then taking the shell off will be:winki::119: .
i have 3 Kato engines, and have Loksound in all three:thumb: . i really like every aspect of Loksound EXCEPT the horn on them:frowns: . the horn on Loksound sound decoders is really low sounding, not loud at all:frowns: , funny thing is, EVERY other sound on them is just fine:thumb: . (yes, of coarse i have adjusted the CV's to max out the horn volume:winki: , it just don't help:frowns: )
DON'T GET ME WRONG, i AM NOT recommending that you get Loksound for your engine, cripes, i give up on recommending anything anymore because i have found what might work great for me, might be a nightmare for the next guy:eeki::119: . take MRC's top two lines of sound decoders for example, i have had GREAT luck with them, i really like them and haven't really had any problems with them:thumb: , HOWEVER, quite a few other people hate them:eeki: . i recommended getting an MRC Brilliance sound decoder to a very good friend of mine, and he has had nothing but nightmares with it

ops: , yet i have at least 25 of them installed in my engines and cant speak highly enough of them:thumb::mrgreen: .
PERSONALLY, i ONLY buy Loksound and MRC's top two lines of sound decoders:winki: , but i herd Digitrax now has sound decoders too, though i haven't tried them

ops: . Tom, if your looking for a sound decoder recommendation, lets hope others chime in with what they think is the best:winki: , i would hate for you to go by what i think, and it not end up working good for you

ops: .
:deano: -Deano