300B or 2a3 SET Class A for Heretic Model A?

@pdreher Keep an eye open for an Art Audio Carissa. 845 SET and a great match with vintage Altec.

PS- I ran Valencias with Model 19 crossovers for a while and those things benefited from some juice. 

@rooze I love the sound of my McIntosh MC30's, but always have an eye out for reputable high quality 845 amps/integrateds to have as an alternate that I can swap with the Mac's for a different flavor.

“It’s really about SETs being a musical instrument rather than a music reproducer. Fun, but it’s not at all accurate to the recording. That profound ever-lovin' 2nd harmonic gets a richness that isn't part of the original recording; that is why I say 'musical instrument'.”
 

To me this is also a specious point, the idea of accuracy in recorded reproduction. I’m looking for something I  like. I don’t want a stereo limited by only sounding good with any particular music or record label. It’s not about accuracy, to me accuracy is anti musical. I want the music I listen to- to be engaging. Accurate is irrelevant, in fact I don’t think it exists. Perhaps an extreme view point. You get into set amps because you want to experience the music not judge the recording. 

“It always bothers me when some asks about a lower power tube amp and someone chimes in with, get a higher powered amp.”

Great posts yaluaka

All good amplifier possibilities by the OP. I'd like to suggest another possibility that would let you have your cake and eat it too -- Why not consider building an Ele-kit TU-8900 from Victor Kung at VKmusic.ca?

I have one and really love it with Avantgarde Duo SD G3 horns. The Ele-kit is an easy build and with the carefully curated upgraded parts that can be bought from Victor with the amp kit, it is a very high performing, lovely sounding amplifier. It is auto-biasing and auto-sensing between 300B and 2A3. Herb Reichert at Stereophile loves his (Gramophone Dreams #74 

For not much more money you could add a Sunvalley SV-S1645D, also from Victor Kung, that uses the 45 tube or with an inexpensive plug-in adapter socket, the the 46 for outputs. Less power than the 2A3 typically produces as a SET, but Oh My! the 45 sound is seductive.

I've both of these amplifiers, having moved way to the other end of the spectrum from my previous D'Agostino Momentum M400 monoblocks, and I am completely happy with the flea powered amps. 

Anyway, just another couple alternatives out many fine amplifiers. Aric is also an excellent possibility and he will build you an amplifier that can switch between 2A3, 45 and 46 if you approach him about it.

Good luck with your journey!

Steve Z