Measured bridge admittance of the Deering banjo with bridge and damped strings but without resonator (red), identical in (a)–(d), compared to (a) result of adding concentrated bridge masses to the measured admittance of bare head: 2.2 g (blue solid), 1.5 g (dashed); 1 g (dash-dot); (b) as solid blue line from (a), but adding stiffness k _s equal to 20 kN/m (blue solid), 10 kN/m (blue dashed) and 30 kN/m (blue dash-dot); (c) as solid blue line of (b) but adding a viscous damper of strength 1 Ns/m; (d) bridge model as (c), but added to admittance from the square banjo model. Dashed blue lines in (c) and (d): Skudrzyk mean-value prediction as in Figure 3.