“TAD” Tubes

I've never heard of "TAD" tubes. Could you possibly mean "E.A.T."?
https://www.europeanaudioteam.com/

Another chi-com knock-off.       https://www.tubesandmore.com/products/vacuum-tube-6550a-str-tube-amp-doctor-premium-selected

These guys have been advertising in guitar magazines seemingly forever.

Yes this is the manufacturer. Anyone tried their tubes of know more about them?

I tried their EL34 and straight from the box liked them better than Gold Lions. 

I use their EL84-STR in my Decware SE84UFO. Nice improvement over the stock tubes and new Mullards I tried.

I'm using the EL84-STR in my Grommes PHI-26, nice rich sound good highs without bloated bass.

How about their 6550 “GE”?

I plan on going with these TAD 6550’s, from Amplified Parts/for my Defy7, 12 matched PERFECTLY,,
After cking out pics, the build/construct does appear to be a <<TAD>> ;-)) different vs the build/construct of the
EH
SVET
Tungsol
Sovtek
Fora few $’s more, Amplified Parts does a perfect match + these TAD’s <<might be>?> close to the <<Legendary> GE NOS 6550;s, which go for $$$$.
So I learned from Richard today at his shop, 6550’s give out after some 2500 hrs,,I listen 6+ hours a day. So this time next year(most likely before) , I will be in the market for the TAD’s.
Nothing wrong with the SVET 6550’s in the Defy, nice all around sonics/bass/mids,, I am looking for a <<TAD>> ;-)), more <<sparkle>> in the highs.
Will post a compare of the Svets vs the TAD’s after arrival. My Defy is having all new Takman Rey (anda pair of 18k REX/Carbon)res installed over the next 2 weeks, Its about 55 res in total
. https://www.youtube.com/watch?v=pc_qExFXryI

<<tad dif build>> correction, look near identical to all other 6550;s
That said, I can attest that each lab 's 6550's/kt88 (same tube) will vary ever so slightly in sonics, The ever popular Gold Lion 6550's did not meet the sonics that i found in the SVET 6550's. 
Next year I will go with TAD's and report back how they compare to my testing in the Defy7.

I need to get with amplified parts and see about a  return <<if needed>>>< I'd hate to be stuck with 12 tubes that do not at the very least match the Svet's. 
My hunch is they will match Svet's in bass/mids , and hoping surpass in the highest registers. 

just doing some research on TAD's  site,,so started cking out all 3 6550 offerings
$55, $70, $100
last i cked out the $100 offering and read this in the descript

<<careflly selected from SVETLANA's production>> 
Bingo
there you have it
TAD = Svet.
and i thought maybe,,,too funny.
Svet's are the <<real deal>> 
I'll just hang with Svet's , why change things up, the Svet's  have a  nice sonic resolution/balance.
I'm skipping the TAD
 https://www.tubeampdoctor.com/en/6550c-svt-tad-premium-matched-sed-6550c-winged-c?c=92

Just some general info: There are no SED, Winged =C=, Svetlana tubes, currently in production.     I really liked them (bought from Upscale), but- the St Petersburg plant burned down, years ago (along with it’s equipment) and SED closed the doors.     New Sensor bought the name (ONLY) and is manufacturing their version in the Sarartov, Russia plant.      Some info from a reputable dealer:  https://www.thetubestore.com/winged-c-sed-6550c                Try contacting known to be honest tube mongers, like the above, Brent Jessee Recording, TC Tubes or Upscale Audio, for knowledgeable info, as to whether they are, "the very same exact tube."      An opinion/observation regarding the new version:  https://www.tubesandmore.com/comment/2577/report                                   Compare the plate and getter construction, to the above (original Svetlana 6550) pic, here:                   https://www.ebay.com/itm/PLATINUM-Matched-Quad-4-Svetlana-6550C-tubes-Russia/184570896793?hash=item2...       Caveat emptor (just sayin')!

Find a picture in which the GE 6650's plate construction, resembles that of the TAD version.       GE:  https://www.google.com/search?sxsrf=ALeKk008s9IFOesJfnELbxiV6qQDoek0rQ:1607987542896&source=univ...    TAD:      https://www.ebay.com/itm/Factory-Matched-SEXTET-Tube-Amp-Doctor-TAD-6550-6550A-KT88-GE-6550A-Remake-...      TAD mentions the GE's triple gettering.     If they have it; it must be the world's weakest, as zero side-gettering shows in any of their pics (haven't seen any up close, however, so: an assumption, on my part)