Eeyore wrote:
Andre Jute wrote:
Which conclusion? That "triodes sound better"
That's your opinion.
or that "there must be an electrical explanation"?
Of course there must be. Added low order distortion of course. It's
basically an 'effect' like SRS or BBE 'sound enhancement'. With toobs you
can't turn if off though
Graham
I am not sure triodes are superior.
They are just 3 terminal devices with inbuilt NFB.
In the 1950s and 60s in many recording studios, gear was used that was mostly
designed by cloth eared
engineers with 100% regard only for numbers and such gear had SHIRTLOADS of
pentodes and beam tetrodes
and transformers and NFB.
We hear the results today on well recorded and preserved vinyl recordings.
Not a digit or PN junction used anywhere.
Great stuff when it turned out right. Was it dependant on triodes?
maybe, but also maybe not.
Why would any engineer use 3 triodes where two pentodes would do?
The final link for us lesser latterday mortals is from recording to speaker,
and triodes are a good choice.
Not necessarily superior IMHO, and i say that after trying
such tubes as the 13Ei SEUL with mild NFB that I believe will give ANY triode
amp some real competion,
providing the power ceiling is the same.
As a later SE amp development I tried a quad of humble cheap EH 6CA7,
actually Sovtek prettied up,
to get 35 watts SE with CFB, and again the measurements were NOT typically
inferior to PP designs and the sound was detailed, sparkling and natural
sounding
and all that anyone may wish for.
I have built SET amps with 2A3 or 300B, and found they gave the best 8 and 4
watts
i have ever heard with 7 db of NFB to reduce Rout compared to tubes like a
single EL84 in pentode
or a single EL34 in pentode, respectively, but with 20dB of NFB needed to get
the same Rout.
The CFB connection transcends the UL connection which transcends pentode.
Triode is somewhere in their between CFB and UL IMHO.
Experimenters may experiment to verify/discount my opinions.
See my web pages for more on such matters.
http://www.turneraudio.com.au
Patrick Turner.