Once you go 300b it’s hard to go back?

Hi Lewinskih01,
I believe that either of these 2 choices you mentioned would be wonderful and make you very happy. Another option is Aric Audio, they can built you a very fine single chassis SET amplifier using whatever output tube you prefer. Mac48025 who posted earlier has 2 amplifiers built by Aric and he says the sound quality, customer service and built quality are first rate. I definitely trust his assessment having personally meeting him.
You have terrific choices. DHT SET are truly excellent with the proper speaker. Best of luck to you. 
Charles

@thom_mackris Everything you wrote makes perfect sense thank you. I should have also been wary of making a blanket statement about tube type. I am sure there are great amps out there using the 300B tube and probably a few mediocre amps using 2A3s or 45s. I know the importance of a good power supply but hadn't thought of driver tubes in quite that context very interesting!

Hi jond,
Yep, overall implementation and appropriate attention paid to the power supply and output transformers are simply unavoidable  vital decision points. 300b amplifiers can range from lush,slow and very colored to outstanding clarity, transparency and naturalness. Depends on the builder and quality of execution.
Charles

While I don't have experience with that model, I haven't heard a Line Magnetic amp that I didn't adore. I've even run them on dynaudios with great results - makes no sense on paper but the music is beautiful

Hi @jond,

Until I lived with Lynn Olson’s personal Karna amplifiers (http://www.nutshellhifi.com/triode2.html) while he was getting settled into his new house here in Colorado in 2005, much of this lush vs. quick 300B stereotype was theory. Yes, I’d heard 300B amps that were more or less incisive, but they still fell within a range that I’d refer to as a "normal" characterization of a 300B.

The material on Lynn's page is a bit dated, as the Ariel speakers are about to receive an upgrade to a horn system he's been designing over the past few years, but the basic amplifier design principles hold true to this day.

Of course, Lynn’s amplifiers are push-pull 300Bs (so this isn’t an apples to apples comparison with anything else), but he used all of the power supply tricks I’m using, and of equal importance is that his driver tube is a 45 (Sakuma/direct heating again - output tube driving output tube).

The Karnas' sound more like powerful single ended amps than push-pull, which plays into my theory that the better various architectures are designed and implemented, the more convergence there is between them.

Cheers,
Thom @ Galibier Design