A method for mitigating stress waves resulting from a blast or impact comprising: collectively choosing a first layer having a first acoustic impedance, and a second layer having a second acoustic impedance to tune stress waves resulting from the blast or impact to one or more specific tuned frequencies, the second acoustic impedance being different than the first acoustic impedance; choosing a third layer having a critical damping frequency that matches at least one of the one or more specific tuned frequencies; positioning the second layer proximate to the first layer; and positioning the third layer proximate to the second layer; the first layer having a length L 1 in the direction of wave propagation, being made of a material having a first modulus E 1 and a first density ρ 1 ; the second layer having a length L 2 in the direction of wave propagation, being made a material having a second modulus E 2 and a second density ρ 2 ; the third layer having a length L 3 , a density ρ 3 , an unrelaxed modulus E u , and a relaxed modulus E r ; characterized in that the first layer is made of a stiff, linear elastic material; the second layer is made of an elastic material; the first and second layers are collective chosen for tuning stress waves resulting from the blast or impact to a specific tuned frequency of f A = E 1 / ρ 1 2 L 1 , the second acoustic impedance being less than the first acoustic impedance being expressed as E 1 ρ 1 ≫ E 2 ρ 2 and such that a ratio of the first acoustic impedance to the second acoustic impedance is greater than 70; and the third layer is made of a visco-elastic material having a critical damping frequency that matches the specific tuned frequency. collectively choosing a first layer having a first acoustic impedance, and a second layer having a second acoustic impedance to tune stress waves resulting from the blast or impact to one or more specific tuned frequencies, the second acoustic impedance being different than the first acoustic impedance; choosing a third layer having a critical damping frequency that matches at least one of the one or more specific tuned frequencies; positioning the second layer proximate to the first layer; and positioning the third layer proximate to the second layer; the first layer having a length L 1 in the direction of wave propagation, being made of a material having a first modulus E 1 and a first density ρ 1 ; the second layer having a length L 2 in the direction of wave propagation, being made a material having a second modulus E 2 and a second density ρ 2 ; the third layer having a length L 3 , a density ρ 3 , an unrelaxed modulus E u , and a relaxed modulus E r ; characterized in that the first layer is made of a stiff, linear elastic material; the second layer is made of an elastic material; the first and second layers are collective chosen for tuning stress waves resulting from the blast or impact to a specific tuned frequency of f A = E 1 / ρ 1 2 L 1 , the second acoustic impedance being less than the first acoustic impedance being expressed as E 1 ρ 1 ≫ E 2 ρ 2 and such that a ratio of the first acoustic impedance to the second acoustic impedance is greater than 70; and the third layer is made of a visco-elastic material having a critical damping frequency that matches the specific tuned frequency. <EOS>