Klipsch Cornwall IV

For sure dbarger tell us about the amps that you’ve tried the CW4 with and about the differences you heard. It sounds like you’ve already tried several with more to come. TIA

On the low-watt topic, I’ve been running my new CW intermittently with an old Moth S2a3 (modded with an external PS). Its 3.5w with Electra-Print iron sound quite good on these speakers, way better than on the Galante Silverdales (99 db) I’d been using in my office system. The Luxman LX-380 snagged for the occasion (18w PP 6L6GC) has more drive and dynamic capability, especially at higher SPLs, but the 2A3 is a special tube and sounds very engaging with the CW4.

An audiophile buddy is coming over this morning for the first time since Covid to listen to all my pandemic impulse buys (long list). We’ll sort through the various amps and topologies in the house to see what works best with the CW4. They’re finally broken in and dialed in and sounding really pretty amazing.

@dbarger, I’ve been itching to try a 300B on these, myself. Do let us know how the LM sounds.

So, for those interested, here are the results in brief. Of course, this is all my room, which is 600+ sq/feet with hallways that fall back from the front wall corners, which means little bass reinforcement. Sources were all vinyl though tube phono stages.

The 2a3 amp simply does not have enough juice to energize the room properly without straining. Would that it were otherwise because I am fond of it and have a wide collections of tubes for it. This amp is an integrated with stepped attenuation, no preamp. At low volume, though, it does all the SET magic, with palpable images and lovely tone. The LX-380 integrated handles the speakers much better, its 18w plenty for unconstrained dynamics. Tonal colors were not a match for the 2A3, with some comparative homogenization of horn voices on octet jazz and classical. Bass was just OK. As a caveat, this amp is new--maybe 100 hours on it; sometimes output transformers can take a while really to come into their own, in my experience. Definitely a good overall sound, though, whether using its internal preamp or a separate (VAC Phi Beta). The best of this session, my friend and I agreed, was unexpected: my highly modified Plinius SA-103 (125 Class A solid state) coupled with the VAC preamp. It controlled the woofers and organized the soundstage in ways that the tube amps could not and delivered a measure of SET-like tonality and richness, likely from the preamp. Dang.

I’m rethinking my approach the CW4. For me a 300B probably would not suffice, as much as I’d like to keep the SET sound. Maybe an 211, 805, or 845 SET. Or I might just surrender to transistors. Naturally, YMMV.

That SA-103 is a great amp. I had one years ago driving a pair of Piega speakers. 
Oz

Another amp that I can highly recommend is the Aric Audio Super KT88/120 SE. I just took delivery of one last week and am currently putting it through it’s paces. This one pairs quite nicely with the CW IV.

Oz