Do NOS Mullard EL34 tubes last much longer than NOS SED (Svetlana) EL34 ?

I have  also had gold Lion KT88 tubes that tested higher than "new" and have many many hours and are still strong. They test almost new still and still are tightly matched. That’s one reason I buy matched tubes from trusted sources

They are my back ups now but still sound good. I can’t even imagine how many hours are on them. A lot

Nope …. I paid the big bucks for NOS MULLARDS for my REGA ISIS VALVE cdp/dac. Note: they are NOT the OEM tubes recommended by REGA

In brief : Now I know why,….. With maybe a paltry 50 hrs on them, one just suddenly and unexpectedly turned black, crapped out, and died .Total loss .F ***ing lovely !

MY TAKEAWAY:

- I won’t be buying them ever again nor will I recommending them either.

- I drank the shite KoolAid marketing BS and I ignored my pro tech’s experience and recommendations to ignore overhyped MULLARDs, in favour of NOS Russki Commie era NOS tubes circa 1961-ish ideally.

why? They will last a lot longer AND they will sound better in his opinion, .

He loaned me his NOS Commie tubes to me for 2 weeks to test drive and compare audio performances.. Yep …he was .right = blindly moving on MULLARDs was a bad choice for me with a regrettable arrogance to ignore his recommendation ..,, I could have, I should have …’ nuff said ….

The Russki tubes were better sonically, and I will now trust his experience that they will have a normal much, much longer life option,  as well as being a better audio performance option,

He was so right . I paid $US 500+ for the NOS MULLARDs that were a Royal FUHBAR. = NEVER AGAIN….Dumbass me …not my finest moment …full stop.

I’ve also A-B’d NOS made in the USA offerings …. Surprisingly damn good and a true contender and no pretender. They are my backups now.

MY TAKE: Be careful out there … choose wisely.

@akg_ca 

The Rega ISIS uses 12au7’s, not el34’s. Additionally, Mullard 12au7’s are among the most robust and finest sounding 12au7’s ever made in the right circuit.

While NOS Mullards are exceptional, all tubes are capable of failure at some point in their life. Unfortunately, you must have found one. From what source did you purchase them? 

Yes … the REGA ISIS VALVE specs are :

This stage uses two military specification triple mica 5814A (ECC82/12AU7) triodes being driven by the revolutionary Wolfson WM8741 ultra high performance digital to analogue converters The output buffer and transformer driver stage uses two ECC88 (6DJ8/6922) triodes.

Regardless , IMO:

- any model brand new NOS MULLARDs should never crap out THIS friggin’ fast….AND ..,,

- the Commie bakeoff options did sound better in MY system :(REGA ISIS VALVE cdp/USB dac / REGA OSIRIS integrated amp / HARBETH M30,2 XD speakers / ATC subwoofer / all CARDAS CLEAR cabling loom )

I bought them from a NOS MULLARD established online specialty MULLARD dealer with a stellar reputation.I’m not blaming him.
Rather, It was my dumbass foolish arrogance to ignore an old school European trained professional tech’s recommendation to bypass the overhyped MULLARDs that grinds on me with my poor choice experience .. I won’t make the same mistake.

@akg_ca 

Why didn't the merchant just replace the tube?

I would have. No problem.