The average sound absorption coefficients for the interior surfaces of eight halls, in which all finishes were completed before installation of seats, were determined from reverberation measurements. When the chairs were installed, their absorption coefficients, both occupied and unoccupied, were also determined from RT data. Five of these halls have lightly upholstered seats, one has medium upholstered seats, and two have heavily upholstered seats. The data are compared with the 15-hall data of Chap. 5 in Beranek [Concert and Opera Halls: How They Sound, Acoustical Society of America (1996)]. A survey of the chair design in those 15 halls has produced a correlation between chair construction and the words: ``lightly,'' ``medium,'' and ``heavily'' upholstered. The new data permit more accurate estimation of reverberation times as a function of frequency than previously found by comparing the details of a hall-in-planning with the constructions and seats of these eight halls.