Assorted Thin Sound Absorber Panels

This is a thin version of the acoustic panel https://www.thingiverse.com/thing:3665832
It consists of a perforated front plate on a sheet of coiled resonators, and has been slotted for experimental forming around curves. The slots may also be useful for installing on standoffs to improve efficacy for lower frequencies.
This version was a prototype that I didn't have an immediate use for and stopped developing until recently I was asked about panels for inside enclosures.

Update: Aug 30, 2020: Included an 'unslotted' version for projects where that may be preferred.