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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
kdude66
1,198 posts
 
Blindjim,

You are the second person to mention those two items to me this week. Are you involved in any conspiratorial activities lately? lol
Is the Linear tube a Dave Berning design?

Yes it's supposed to be a secret but we are looking for more members

All the Linear tube audio gear is greatly influenced by David Berning and has his blessings Offcourse.

I don't know where a guy could listen to the same gear I have but I've been told that Linear tube audio is getting a set of the Tekton Electron speakers to demo their amps with in their showroom.

I went to a shrink many yrs ago and I was told that I'm a hopeless case and they really aren't qualified to help me.😃

Best set of luck to you in your search,

Kenny.
inna
5,245 posts
 
You would do me and us all a favour if you listened to Ypsilon before buying anything. By many accounts, including Michael Fremer's, it is one of the finest brands available. Yes, their 100 wt/ch integrated is $25k new. And Gryphon Diablo 300 is another one to hear. Both designers are highly respected. 
czarivey
4,494 posts
 

those low-powered amps sound good in completely empty room and speakers firmly attached to corners so you can hear somethin'.

atmasphere's avatar
atmasphere
7,068 posts
 
@blindjim , all the comments regarding speaker efficiency are spot on.

And you are quite correct that different brands of power tubes are going to sound different. Once you settle on a particular power tube type, then you sort out which brand of that tube to get. The choice of power tube type is heavily dependent on which speaker you get!!

The one thing you want to pay attention to is the way SETs make distortion. In that regard, they are very very good at low power; distortion falls to the point of being unmeasurable (which is the source of the ’amazing inner detail’ for which so many SETs are known; the amps we make are some of the very few push-pull amps that share this low power lack of distortion character). But at full power, the typical distortion is in the neighborhood of 10%.

SETs are known for being quite lush and very dynamic. Both of these properties are due to distortion- the 2nd harmonic brings the lushness, and at powers over about 20% of full power, the upper harmonics cause the dynamic properties on account of the way the human ear perceives sound pressure.

You really want to avoid the higher ordered harmonics! Not only do they cause the amp to sound dynamic, but they will also cause the system to sound loud and shouty. You will see a lot of people talk about the fact that their system plays as loud as they want; this is **often** caused by the distortion and not the actual sound pressure. A good system should **never** sound loud!

To avoid this, the speaker simply has to have the efficiency such that you don’t exceed about 20% of full power of the amp you have in mind. This will have the amp playing its most transparent and with its smoothest qualities. Generally speaking, this means that in most cases, a speaker of less than 100db is not going to be suitable. I am full aware that there will be many that read this and will dispute these words; my recommendation is to reread this post! For these people, if your system is not set up by this rule of thumb, you really aren’t hearing the finer qualities of your amp, no matter how enjoyable it might be.
kdude66
1,198 posts
 
atmasphere,

Wow just Wow,
Incredibly well written and explained priceless information IMO.

Thank You,

Kenny.
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