Best Values In Speakers To Pair With Coincident Frankenstein MKII Monoblocks?


A good friend who I have gradually been introducing to quality audio for the past few years has decided to start by putting together a SET system, based on demo's, attending both Axpona and Rocky Mountain this year, with me. He started his new system by purchasing a mint condition pair of the superb Coincident Frankenstein MKII mono's, and we are now currently attempting to match these amps up with a suitable pair of, at least somewhat reasonably priced, suitable high efficiency  speakers.

His room is 13.5x15. We would appreciate any insight, recommendations and suggestions, from you, of speakers that would pair very well with the Frankenmsteins. His budget is $5k or under for a used pair (to maximize his budget). Any speakers within the budget, that you have heard working well with these amps, is fair game, excepting any speakers made by Coincident. I would appreciate it if those are excluded from the discussion. Most are too expensive anyway, and there are other reasons for the exclusion. Not that Coincidents aren't fine speakers, but they don't fit into our scenario. Thanks for any help with this, it is greatly appreciated. 
nightfall
06-28-2019 1:30pm"If you haven't already, take a look at SONIST speakers. The concerto 4 can be found used for 3 to 4 thousand dollars and would be a great match for your new amps!
Good Luck, TISH"

Thanks for the suggestion, Tish. I've heard a bit about Sonist, but these look very interesting too and there are some Concerto 4's to be had in exactly the price range you mention. No worries about driving them with 8wpc?
I've heard the AN "E" speakers in their most basic incarnation, and they sounded very good indeed.  All those "extras" seem to me to follow the law of diminishing returns (mainly more "detail").  Call Deja Vu in Wash DC, who are Audio Note dealers and experts in low powered tube amps.
@nightfall To answer your questions the designations for AN speakers K, J, and E, don't refer to the cabinets getting better just bigger. All 3 models use the same 8" bass driver and the J and E have the same 1" tweeter the K's tweeter is 3/4".

Within each model there are variations of levels of internal wiring, inductors, voice coils etc. My J's are the J-lx internally wired with AN Lexus copper cabling. Sensitivity is 93db the E's are slightly more sensitive at 94db.

+1 @twoleftears Deja Vu is my local dealer and where I bought my AN-J's.
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keithtexas244 posts06-28-2019 10:13pm
"Another you may consider is the Omega SAM monitor.
Good luck; great start with the Frankensteins."

Over the years, I've heard some very good things about Louis and his speaker designs. I've been intrigued, but there are almost no reviews of his products (with the exception of the 6 Moons Hemp review)  which is concerning.