cff-version: 1.2.0
message: "If you use or build on this disclosure, please cite it."
title: "Non-Contact Control of Drumhead Resonance Decay by a Proximity Acoustical Resistor"
abstract: "A defensive publication disclosing a method to shorten and tune the decay time of a drumhead's resonant modes, including selective overtone damping, using an acoustically resistive material held in close proximity to but not touching the drumhead. Energy is removed from the vibrating head through its near-field air motion by acoustic resistance (viscous/thermal loss in a porous or perforated element), without contacting or loading the membrane; geometry selects which modes are damped. Includes the physical principle, a family of embodiments with original drawings, and measured demonstrations (spectrograms, energy decay, and RT60) from struck-drum recordings. Conceived by the author in the late 1970s; never patented; published as prior art."
type: article
authors:
  - given-names: Calvin
    name-particle: D.
    family-names: Rose
    email: calvinrose18938@gmail.com
date-released: 2026-07-26
license:
  - CC0-1.0
  - Apache-2.0
keywords:
  - drum
  - drumhead
  - membrane damping
  - overtone control
  - acoustic resistance
  - porous absorber
  - decay time
  - RT60
  - sustain control
  - non-contact muffling
  - percussion
  - defensive publication
  - prior art
