My Heresy III "Capitol Records" edition (meaningless relative to other Heresy IIIs other than the "special" ebony finish that looks like dark purple) pair are built like little tanks, and if you knock on the sides you get nothing more than a bruised knuckle.
Klipsch K Horns (the new AK6)
At $15k, eeek!!!!! and their hard to drive, forget your 2A3's on these
https://www.stereophile.com/content/klipsch-klipschorn-ak6-loudspeaker-measurements
Cheers George
https://www.stereophile.com/content/klipsch-klipschorn-ak6-loudspeaker-measurements
Cheers George