That's a good question, and we hear it a lot. When it comes to soundproofing, there are basically four wall types, and I have listed them from my least favorite to my most favorite. The best walls, in my opinion, are going to be acoustically decoupled to provide excellent sound isolation.
Decoupling is the essential starting point. After that, we look at potential space savings and the ability to accommodate the weight of heavy items - like kitchen wall cabinets with dishes - that will attach to them.
The four most common ways to build a soundproof wall are:
#3: Clip & Channel Wall
The Clip & Channel Wall is nice because it takes up little space, yet still provides decoupling of the drywall. This wall isn't optimal for a double door airlock, and you also can't hang heavy things like a kitchen wall cabinet filled with 500 pounds of dishes. This wall is thinner but has those couple of limitations.