I've always had a certain fondness for Large Advents - had a pair most of the way through college, and later added a second pair. Great sound with the infamous stacked setup, to be sure.
But much as I liked them, the Advents eventually made way for a pair of Infinity 2000A's. These had 12" woofers, about 6" midranges, and four rectangular RTR electrostatic tweeter panels mounted at varying angles in an area open to the front and rear... one of the earlier 'direct/reflecting' designs. The 12" woofer delivered very solid bass (no sub needed), but the electrostats were the 'secret sauce' for a very smooth upper range all the way to at least 20k. I still remember them fondly as one of my all-time favorite speakers. The 2000A was kind of a 'cult classic' - one of the true 'sleepers' of the era for the price. I bought mine very slightly used for about $250, and they literally blew away speakers selling for many times that amount.
Unfortunately, one of mine was stolen out of the moving van during a relocation, so today I have only one half of the pair (why would anyone steal just ONE speaker?) I'd love to grab another pair someday (there's a pair in very nice shape currently offered on eBay for $799), just to see if they still impress me as much as they did back in the early '70s.