According to the link you yourself provided, the unit does include a Tsunami sound decoder:
Now equipped with a SoundTraxx Tsunami Digital Sound Decoder
I have a couple of the UP models actually, and they sound great. Most of my current layout is 28-30" radius, and the overhang is fairly minor. I do have one section of 24" though, and the overhang is quite significant. Operating on my 24" seems like a stretch for these big engines. I'd imagine that it would look even worse on 22", and I'm not sure how reliable the engine would operate on 22".
If you're looking for sound in a smaller frame, I also recently purchased one of the MP-15s from Athearn, again with the Tsunami. The engine looks, runs and sounds great. It has made all the neighbors around the industrial where it operates quite angry.