When I spoke to Klipsch (Trey Cannon) after I got my mismatched (1960s/70s) pair of KHorns, since one needed a new woofer and everyone said to upgrade the AA crossovers, Trey said some of the networks were not considered very good by Klipsch engineers, after the fact, and should be avoided. Maybe the AK2 or AK3 or AK4? Not sure which. A lot of people, even at Klipsch, seem to prefer the AA. But each model’s xover was voiced accordingly.
I upgraded my AA to ALK extreme slope, Beyma tweeters, ALK wood mid horns ($$$$$). Wonderful silky sound but much too relaxed, less dynamic, for us. My wife was extremely disappointed. She said the improvements were a trade off that defeated the whole point of having such big speakers. Then I went to Crites AA xover and tweeters. Much simpler, more like stock, which we very much preferred.
I recommend that you do NOT enclose the backs (a practice begun after PWK’s passing). Stick to stock. (That’s just my 2 cents.) If you have good corners, let the walls extend the bass bins—as they were very well designed to do. Seal the KHorns tightly into good corners (foam pipe insulation on the horizontal plywood where they meet the walls, and rubber garage door seal strips attached, on both sides, to the full height of the tailback); try to have 4 feet of uninterrupted wall, the height of the bass bins, extend in all four directions; put them in rooms (on the long wall) with ceilings at least double their overall height (104” + / 8.5’-9’ minimum). I cannot stress enough the importance of tall ceilings with Klipschorns. Mine are in a 10’ tall room. My wife and I once auditioned them, set too close together, in an audio store’s basement with 6.5’-7’ ceilings. Comparatively, they sounded really, really bad there. (There, my wife absolutely hated them.) I really am convinced that KHorns need cubic feet (tall ceilings), not just big rooms, to unleash their dynamic power and to recreate a big believable soundstage.
Klipsch also recommended that you can cut a triangular piece of Masonite for the floor under each speaker (the depth of the speaker—28”—and extending diagonally across the floor to both walls and, going back to the corner, along each wall)—if you have porous wood floors or really deep shag carpeting. This helps to seal the floor to the walls/speaker as one completely (relatively speaking) closed, flared horn, from the floor up.
FWIW: My own corners are not perfect in every one of the four sides of the corners, but sealing them helped; and I’ve never felt, really, that they lacked for bass.
If they work fine as is, I also HIGHLY recommend that you live with them stock for at least 6 months/1 year before you consider upgrading anything.
I also recommend quiet, high quality tube amps. But SS has its own strengths.
Also, KHorns are in a different league than Cornwalls or La Scalas (just as the Jubilee is in another league than the KHorn). If properly set up, all things being equal, the Klipschorns will have deeper resonating bass, more nuanced mid-bass (a huge perk), a bigger, taller, deeper, wider soundstage, and more dynamics—more of the sense that you’re in a live venue, especially on big orchestral and rock pieces—than the Cornwalls. This is partly to do with the fact that the midrange horn is closer to head-height. But the bass bin is just better. And sealing the KHorns to the walls pressurizes the room—as if you’re inside the music. Bigger horns—bigger sound.
Congratulations! Enjoy them. They’re a lot of fun. PWK called the KHorns “a tinkerer’s dream.”
