Have Wavelength 45 Customs, 2 throbbing watts into Beauhorns with Lowther dx-4s. Have no idea what Paully means about contamintating sound. I use a TacT to intregrate stereo subs and tame the upper mid rise of the Lowthers.
Who, Little Feat, Arrowsmith, Red Hot chili Peppers, even Ted Nugent (my secret shame) can tear down the house, but Laura Hunt on 45 RPM sounds great and chamber music does just fine. "Firebird Suite" is like a physical contest and reminds me of my days playing principal trumpet in front of the trombone section/sheer horsepower without strain.
30 years in and dozens of speakers, thousands of Watts, ss and tube, etc. under the bridge and this is one of my three best systems and by far the simplest.
Zu's are okay, but you may not be able to go 45 or 2a3's, may have to stick to 300b. Be careful, as the speaker is the ticket.
BTW, Beauhorns STINK without careful placment and stereo subs, IMHO.