As mentioned, the drivers in the AR-58S are identical to those used in the AR-9 Verticals series, and should be expected to render a "brighter" result when compared against the classic-era AR-3, AR-3a, and AR-5. Apparently, the only difference between the 58S crossover and the AR-91's is the level controls in the '91. After re-capping - and possibly installing the AR-91/92 crossover - I think Roger will find a sound that is very consistent with the rest of the Verticals series: improved clo