least a first predetermined assembly resonant frequency substantially replicating a similar measured or estimated resonant frequency e g a pump housing resonant frequency note that an adjacent annular unconstrained area 60 of viscoelastic reservoir element 52 remains open to pumped fluid pressure note also that adjustable preload flange 30 may be adjusted in effective radial extent and or longitudinal position note further that annular constrained area 62 and annular unconstrained area 60 are substantially concentric and adjacent thus for a tunable suction valve subject to longitudinal i e distally directed compressive constraint applied via preload flange 30 to annular constrained area 62 annular unconstrained area 60 will tend to move i e extrude proximally relative to area 62 the oppositely directed i e countercurrent movements of constrained and unconstrained annular areas of viscoelastic reservoir element 52 create a substantially annular area of shear stress finally each circular tubular area 58 is substantially filled with at least one shear thickening material 80 see fig5 chosen to achieve at least a second predetermined assembly resonant frequency similar for example to the first predetermined assembly resonant frequency note that fig5 schematically represents a partially sectioned view of an instantaneous configuration of the shear thickening material 80 within circular tubular area 58 referring to fig1 and 2 in greater detail a tunable check valve assembly tunable radial array embodiment 99 comprises viscoelastic body elements 50 which comprise in turn reservoir central element 52 coupled to groove peripheral element 54 via radial fenestration tension elements 56 elements 52 54 and 56 are disposed in i e integrated with and or lie substantially in reservoir 16 groove 12 and fenestrations 18 respectively to provide a tuned radial array having at least a third predetermined resonant frequency an.