My Sound Dampening Enclosure for almost finished CNC Router

[routercnc]

Looks good. Box in box is a classic solution and with minimum structural connection between them should work well. Note that the surrounding inner box will amplify the sound inside which makes the outer box work harder. The carpet will help with absorption but only at fairly high frequencies. If you can line the ceiling with something thicker and fluffier it will help.

Services in and out are best done with long trunking lined with absorption, so don’t just go straight through each panel but start at the top (say) of the inner and bend 90 deg down to run down the void, with a rubber coupling in the middle, then bend 90 and go out of the outer panels. So the upper trunking is mounted to the inner panel and the lower trunking is mounted to the outer panel. You can get rectangular trunking which might fit depending on the gap size.

Good work