Member's recommendations for tube amplification

@atmosphere 

For what it's worth, I filter out 70Hz (-3db) and below (-12db @35hz) from the amps and speakers (using a pair of passive filters) and I am letting my ML Depth i subwoofer handle the bottom range; IMO, this has worked wonders in driving the Omega speakers with the Franks with substantially less distortion; I don't detect any distortion, but if there is, I have no objections to it :)

For what it's worth, I filter out 70Hz (-3db) and below (-12db @35hz) from the amps and speakers (using a pair of passive filters) and I am letting my ML Depth i subwoofer handle the bottom range; IMO, this has worked wonders in driving the Omega speakers with the Franks with substantially less distortion; I don't detect any distortion, but if there is, I have no objections to it :)

The point is that unless the amp is outright clipping, the ear does not detect the distortion as such- in almost all cases, the ear converts distortion into tonality. But because the ear also uses higher ordered harmonics as a loudness cue, if there are higher ordered harmonics in the signal, the ear will hear that as louder.

In an SET, the higher orders start to show up when the amp gets to about 20-25% of full power. Since music has most of the power in the transient leading edges, if the distortion is only showing up there it will come off as 'dynamic'. Lots of people like that (often though without understanding how its happening) but it certainly isn't natural!

If you really want to hear what an SET does right you need a speaker that is efficient enough that the 20-25% of full power is not exceeded.

 Also consider these Audio Note monoblock amps for sale; 
300b parallel SET monoblock amps. 

http://www.usaudiomart.com/details/649306274-audio-note-300b-parallel-legend/

Music Reference RM 10 would also be a sweet match with your DI speakers in my estimation.  Great little stereo amp that has proven itself as a winner for decades now.  

@larryi Thank you very much. Great points.

I understand the limitation of the 300B and it happens to be one of the tubes I haven’t been a fan of in the past.

I’m open to reconsidering since I keep reading how, in some implementations, designers are getting a more ’modern’ sound from their 300B amps.

In the case of one of my speakers (the Tekton Double Impacts; soon to be the SE version), based on what I’ve learned about it over the past six months, I believe a 300B amp will pair well, even a classically voiced 300B, and probably to my liking. Especially so if I’m driving it direct with the Metrum Adagio.

I like that there are many options in terms of 300B amp makers, availability, and for sale and resale.

I have a preference for 2A3, but the power output is a real concern. As you mention, a parallel design would likely meet my lower output threshold. Likely a pricier option and not as easy to get right, as you point out.

I’ll take a look at Synthesis and Audio Note as well as research the 6L6 amps.

A pair of used Cary 805s would, I think, tic every box you've specified.