So it is impossible to know if a speaker is any good or not. Those originals were not even close to the best on offer in 1957!
Particularly since they weren't introduced until 1968. It was one of the better speakers of that period, really only second to the larger KLH Model 12 that had a larger cabinet more suitable to the woofer. I owned a pair of 5's for decades and enjoyed them very much. The main problem was the usual lack of attention to driver layout. The parallel dual midrange units interfered with each other and with the woofer and tweeter, producing a suck out in the lower treble, upper midrange. But in terms of neutrality, it was miles ahead of the AR3 and AR2 series, and sounded very much like a Dynaco A25 with deeper bass reach.
Contrary to the marketing hype surrounding the current reincarnation, the original Model 5 didn't sell particularly well due to its high price of $360/pair and the soon-to-be-introduced large Advent. However, the midrange units were very high quality acoustic suspension drivers that were used full range in the KLH "suitcase" all-in-one speaker with active equalization. I worked up a revised crossover for the 5's a few years ago and would put those up against a whole lot of contemporary designs. Finally, the original 5's used a genuine acoustic suspension woofer, which relied primarily on the compliance of the trapped air in the cabinet to control woofer motions. The re-imagined 5's use a sealed woofer, but not one with a high enough compliance to qualify as true acoustic suspension in design.
arguably the best speaker of that period, but suffered the
