After having had my new VLBB for a couple months now, I don't think the lack of a baffle is the problem. The rest of the engine's sounds are plenty loud to me and just as loud as any other recent Legacy engine. Relative to the other sounds though, and compared to another big Lionel articulated I have with a very similar whistle (Rio Grande Legacy 2-8-8-4), the whistle is noticeably more quiet. It's almost as if there's a max volume limit for the whistle sound effect only that's in place for some reason.
Adding a baffle might make *all* of the new loco's sounds a little louder and punchier, but it definitely won't make the whistle by itself louder versus the rest of the effects.
I was searching for a solution to my new $2600.00 weak sounding whistle VLBB and came across this thread. I agree with Blue Feather. I just recently bought a VLBB #4019. I test ran it at home, and all sounds, "chuff", "Blow Down" , "Pop Off" sounds are fairly loud and "throaty" with the exception of the Whistle sound. When I ran my BB at my clubs layout, you can barley hear the whistle, with the chuff sound from my BB and other engines running on the layout. Again.... The Pop Off, Chuff and Blow Down sounds are strong. Assuming everyone is correct that it's either the lack of a "baffle" or speakers out of "phase". Then why are all other sounds strong and loud but the whistle weak (low sound)? So what is at play here is, Lionel made the whistle sound come out of one speaker, and it probably needs a baffle or speaker is out of phase???
When I got close to the engine to listen for the sounds, the chuff come out of all 3 speakers, as do the blow down and pop off sounds. I think it's more of the sound file that Lionel used and the whistle came out a little too low. My two cents..
On another note: I had 3 screws fall out of the Big Boy when removing from the box and held it upside down in my hands and a small magnet from underneath the front walkway (which I found where it goes and glued back). I inspected the engine closely and all seems to be intact and the engine ran fine, so I did not want to disassemble incase I have to send back for warranty work. My first and only Vision Line, and for $2600.00 Lionel has to get their act together on quality control. Sorry for the rant. I do like my BB and hope it runs for many years.
See my YouTube video and check out the sounds...
https://youtu.be/JvTalKa0k04?si=Pnc44VT2ALVBOlER