Better with age?

[greenboy]

...but, what if someone were to build a cast of the TL606, pour some light weight cement into it creating a cast cement box and then mount an emminance kappa driver into it... Would this be ridiculous good or ridiculous bad?

Kind of a waste since much better higher-force drivers exist that could actually benefit from the rigidity - but they are mainly used for portable applications. The TL606 is just a shelf-port design for specific driver, there's nothing otherwise notable about it.

 

[Matt Dean]

The TL606 is just a shelf-port design for specific driver, there's nothing otherwise notable about it.

Understood... just using that as an example.

since much better higher-force drivers exist that could actually benefit from the rigidity

IYO, what design would benefit that kind of rigidity and what driver would you use?

 

[greenboy]

Any high-force subwoofer with scads of xmax.