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Sonic qualities of SET output tubes?

Can you readily identify a 300B, 2A3, 805, 211, etc., amp’s sound with your eyes closed most of the time?


If so, I’sure would like to hear from you.


Amplifier design and the technology utilized within its confines decides the ‘voice’ or influence it will yield as much or more so than merely the output tubes the designer has chosen to use.


I get that part emphatically. One must hear the amp regardless the type of output tube technology on hand.


And yes, some Pentodes and Tetrodes are used as Triodes but are not indeed triodes by their specific architecture. That’s OK, just focus on their use as Triodes herein, please.


There are however certain tube types, irrespective of vintage which have basic undeniable sonic colors or characteristics, apart from their electrical aspects which keep attracting people to amps which use this or that tube in its output stage.


Some love 211s. some adore 300Bs. Some love EL34s configured to run as Triodes. I have an affinity for the latter. So far anyway. This topic could change my mind.


Has your own experience informed you what this or that output tube’s natural flavor regularly announces itself to be so you can have a reasonable expectation of its general presentation?


What sonic attribute continually attracts you to a particular SET tube design, 300B or some others?


Or, conversely, what is it about the sound that would bring you to covet a 211 amp over a 2A3, for example.


Why as another example, would you pick a 2A3 amp over one using 805s or 300B, 211, etc. or vice versa?


Removing ‘vintages’ and electronic or electrical qualities from the argument, what sonic attributes for the more popular S.E.T. amp output tubes have you determined seem to persist in their particular DNA?


I’m asking for input from those SET tube devotees to lend their experiences and knowledge on the subject of what tube sounds like what irrespective of the SET application, generally speaking.


My goal is to try getting a better feel for which SET Tube amp design, if any, I’d want to pursue and possibly invest heavily into going forward as the soul of a new system.


Tremendous thanks to all!

blindjim

Showing 2 responses by whart

whart's avatar
whart
2,967 posts
 
If you are asking about SET amps, I don't think the question of speakers is a secondary one. I've heard speakers that can play with SET amps but aren't really sustained by them and benefit from greater power. I think you have to treat the amp-speaker combination synergistically. Don't mean to sound patronizing, I gather you have been around the block. 
I'm listening to two very different systems right now- a horn system with Lamm SET amps and a Quad ESL with old Quad II amps and top notch glass. Both are marvelous, but the amps are working well within their parameters and mate extremely well to the specific speakers. 
whart's avatar
whart
2,967 posts
 
@blindjim - the horns are Avantgarde Duos which I have since around 2006- so they aren't one of the newer models but benefitted from some of the running updates prior to the Omega modification. Their internal woofer system is augmented with a pair of 15" subs that crossover very low- e.g. 50hz on a step- 24db/octave slope. With some adjustments to volume and phase (and a little DSP box only on the subs), they give some additional heft and dimension to the Avantgardes without distracting from their coherence. Even that speaker, with its 104 db efficiency, can benefit from a more powerful amp, but there is a synergy with the Lamm ML2, which I like very much. It's instructive to listen to them against the Quad ESL--the Quads are so compromised in certain respects, but their vital strength--the midrange--overcomes most of their shortcomings. 
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