I bought a pair of these brand new from Bay Bloor Radio for about $400 in 1979. They replaced my Polk Monitor 7s, and were driven by a Marantz 1070 amp, then an NAD 3020. They're as good as I remember, and are much better than the 22.2s I had a couple of months ago. The hyperdome tweeter is known to fail, the leads from the voice coil becoming corroded by the adhesive used in their manufacture. There is a shop in Halifax which owns the original manufacturing equipment, and 'remanufactures' the tweeters for about $300/pair. The tweeters on the pair that just arrived are working and sound fabulous.