There are a LOT of “sax enhancements” you can buy. Some, like ones made by Oleg, are great. I have used the Oleg palm key risers since the 2000s. Highly recommended. These type of enhancements fix a functional issue with the saxophone.
Then we get to that are…..well……..subjective. The weighted screws, the “tone tablets”, and the Klangbogens of the world. Do these work? I have no idea. Perhaps. I’m not really keen on blowing a lot of $$ to find out. Some of the theories on how they work seem rather suspect.
However, I did come across this tonight, and this actually makes a lot of sense to me. The Mr PS is a little half circle you put on at the TOP of your saxophone neck pipe. That little “dead” area before the cork starts. The area that essentially should be a small “gap”. You put either a metal one or a plastic one there, and then you have a transmission source from the vibrations of the mouthpiece to the rest of the horn. Now that actually makes a lot of sense to me.
Here are some videos about it here.