Soundproofing Q - fill wall spaces or not?

Liebe zeit

Silver Member
I'm all set to build a drum cell in my basement and I feel happy about most of the construction (battens + resilient bar on walls/ceiling; acoustic batten cradle floor etc etc).

But I seem to be seeing conflicting information about whether to fill between the battens with any kind of damping.

I understand - at one level - the principle of 'dead air' and leaving air gaps when aiming for isolation. But does filling gaps between battens make the air deader than just an air gap?

Any ideas anyone?