EL34,KT88,KT90,KT120,KT150
I think its high time we all come together to present our experiences, testimonials, opinions, and best guesses.
Ok so my journey in power tubes has been rocky , shootouts too quick to see who really won the draw.
I had kt90’s..Not bad, in the Defy7,,not bad at all,,,then I madea good deal on some 88’s, and swaped out the 90’s,,,Maybe a bit superior, but really close,,,can not recall the shades of dif, and now the new 90
’s were sold off at 50% loss.
Then I read somewhere, maybe here on audiogon,,or another forum,,the 150’s were **killers**,,so i thought
~~Bigger MUST BE better~~I mean just look at the 150, really cool looking 21st C High tech power tubes
https://www.google.com/search?sxsrf=ALeKk0029KWREk7QDaFsPD8olvPrEySraw:1589600030456&source=univ&tbm=isch&q=kt150+tube+image&sa=X&ved=2ahUKEwjFuJnJubfpAhUDiqwKHac1B2sQsAR6BAgKEAE&biw=1536&bih=750#imgrc=637YiieWd71i3M But as my latest YT vid shows,,~~Bigger is not always better~~~ in power tubes. I only listen to CM, which requires a power tube which will reflect the best image for instrumental, which is FQ range say 2K-8K hz.
These fq’s seem to become all ~~muddled~~clumped together~~ which means the mids sound stretched, if not a ~~Stressed Midrange~~ sound.
To be frank, I hate the Kt150 in my Defy7. Sure the sound is slightly *bigger, more bold**, yet gives up what the KT88’s offered, a tighter mid fq range.
At least this is my assessment so f far,,i will bring the 88’s back to my tech guy and have him ~~rebias yet again~~ for the 88’s.
A long time member here who knows jadis well, suggested his fav tube for jadis curcuitry is the EL34,,which might even be a superior match for my style of muisc,,classical in all its forms.
can not make that expense at the moment.
Just consider, , I figured the KT150 with its large construct would deliver the wider, deeper fq’s in all areas. vs the smaller power tubes...
Its quite possible it is the EL34 tube which will deliver the sweet crystal clear, highly defined, separation in the orchestral sections,,,,a tube i completely over looked due to its ~~wimpy construct~~ vs the massive KT150.
So we should all consider which style of music, or better~~which power tub is preferable~~ to each music style.
Jazz
Jazz w vocals
Rock/blues
Lite Classical
Heavy orchestral.
I would tend to say the big power tubes/single ended are finest match for easy jazz/vocals. 300B/805 etc. But then now the speaker limitation gets involved, low eff vs high db impedance.
After rolling back to the 88’s, i will post a new YT upload..
The thing about rolling tubes, is ~~memory~~ how well the nuances are noted and registered in the experience.
I think I have the 150’s locked in with several reference cds to say what the 88’s bring to the muds vs what the 150’s did not do so well with.
Thing is, there will be new M caps installed and that also might influence the shoot out for midrange voicing. The ~~all things equal~~ law , will be dismissed here as i have no intention of listening to the 150’s with new caps, then bringing amp back to tech for rebiasing for 88’s.
So my critical comments on the 2 power tubes for mid fq’s, will be ~~biased~~ as new Silver Gold EVO Supreme’s are installed with the 88 setup.
later on I will order the EL34, which as i say, Trelja and my tech both are in favor of the EL34 for the Defy.
That shootout will be later this year.
based on my experience of the EH KT90,,I’d say the 88’s supplied a slightly superior sonic sound stage/,,but midrange fq’s were about equal,,at least best to recollection.
The dif was subtle and hard to decipher in a A/B compare. Blindfolded.
Another factor which could be mushing the mid fq’s all lumped ina glob,,is the preamp.
Preamps make a huge dif on how a power amp will voice.
,
I note Jadis makesa Intergrated I50 specifically designed for the kt150 tube,,I’d love to hear it and see how well the 150’s perform in classical/jazz mid fq range.
Hi-Fidelity definition?
Or
Muddled mid fq’s? (the I50 most likely will accept other tubes ie 88’s).
I recall someone on a YT vid comment was adament,,no , in fact, i was the one stubbornly refusing to understand/accept his opinion the EL34 was ~~best mid range tube made~~,, He really took offense at my follow up comment promoting the 88 as best all around power tube.
Now that said,,I would surmise /guess , the el34 can not provide the punchy bass which the 90/88 pounds out.
However a certain pre which is on my wish list , has a 2nd pre out for a sub amp/woofer sitting in my closet..which will make up for the slight lack of bass slam( percussion) missing in the EL34’s temperment.
Anyone care to share their ideas, experiences in tube rolling and which tube might best suit each musical genre.
These discussions may offer valuable info which may lead to better decisions in choosing the power tube which best suits each musical genre...
Last note,It will be a big surprise if the EK34 ends up dedliveringa superior, tighter mid fq section in my classical/vocals, vs the mighty 150..
The Q here is , will the EL34,,anemic in appearance sitting next to the ~~beastly looking~~ 150,,,will this humble, original designed pre all other power tube year built/designed,,,will this tube deliver the mid fq's hat i have been searching for all these years???
Also will the EL34 not look ~~awkward,~~ sitting in sockets with 3 huge trans sitting behind?
.
p
