SO I played all saxophones for five years now, and during concert or practices, I have an amazing tone on my sax. But I leave my sax in my house overnight, next day I can bairly make a note without sounding airy and busting my lungs. Why would that be? I am using 3 or 3.5 reeds, a rubber mouthpiece and am using a YAS 275 saxophone:

(https://www.google.ca/search?q=YAS+275&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjB_uPKjsbJAhXHbB4KHdv9CVkQ_AUIBygB&biw=1920&bih=955)

Any help would be appreciated.

Well it is very simply because you sound better with other instruments backing you up. I suggest playing with a soundtrack with melody and then just the background harmony. There is a small chance you can't play as well when playing without another melody to follow. If this is the case you a soundtrack or recording until you get the jist. Happy playing!

Yea I come from a music production background and one thing you learn is that the ear actually takes all the multiple same sounds (like a sax section) and takes the AVERAGE sound created by all of the saxophones, rather than hearing each one individually. That's probably why. Keep practicing!