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

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

@charles1dad  understood and agreed on power supplies I am sure i
will listen to a 300B amp again someday!

@thom_mackris interesting looking amps thanks for the link. On the subject of the amps being push pull I am a fan i’ve heard and loved 45 and 2a3 pp amps.

Lynn is a brilliant theoretician and I feel fortunate to live in the same town - bouncing ideas back and forth with him. Having his Karnas in my house for those three months was revelatory.

Check out his essay "Illusion Engines". Some of it (written in the mid-90’s) is a bit dated, but the concepts are still viable (to me): http://www.nutshellhifi.com/library/illusion-engines.html.  He's primarily a "speaker guy" (having designed first for Audionics in the '70's), but he digs into all areas of audio with passion.

Cheers,
Thom @ Galibier Design

Hi Thom,

Your comments on driver tubes and circuitry is spot on. Once you chose a particular DHT tube, separates SET amps is really the driver circuitry. Followed by the OPTs. Or do like I did, which is to ditch the OPTs altogether OTL. My Berning 300B SET OTL (new "Siegfried") is my current fave SET amp and looks like it will remain for a long time.

At home I use an AN (UK) Meishu Silver with WE 300b into Loth-X Troubadour 104 db speakers. Recently I was given an old Audio Note Japan Ongaku 211 (GE tubes) on long term loan which now sits side by side with the Meishu. I am in the process of making comparisons (very little rapid A/B switching, more long time listening then switch..this is the best way to see differences IMO) but it is quite interesting to be able to compare one make with two different SET arrangements. Interestingly, the first few weeks of testing show a lot less difference than I was expecting. The AN UK Meishu has a surprising amount of scale and better mids than the Ongaku, but the 211 additional output helps even out the performance throughout the frequency range. Given the price difference, the Meishu seems to be ridiculously good. We have an AN Tomei 211 (Elrog tubes) in our mastering studio which we use as a daily monitoring workhorse. It is fantastic, and being in an acoustically neutral environment where we are not thinking audiophile, but rather working, it provides a reasonable "control" reference. In conclusion (so far), a well executed 300b married with the right speakers will not be better, but can hold its own against the best 211 set up. Also note that if you are into tube rolling, one gets more tonal differences between 300B tubes than 211 tubes. So perhaps these WE 300B early reissues might be one of the main reasons the Meishu is up there?