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6J52P pentode driver?

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Hi
A while back some members were talking about the 6J52P is quite similar to the D3A, so I bought some on eBay. Has anyone tried it as a pentode driver? Can you share your experience?
Many Thanks!

I've had several sets of 'new old stock' 6J52P bought on Ebay from Ukranian sellers . Most were poor quality pulls :- junk ! Avoid seller 'holms_ua' especially , I've just been sent 20 dirty used pulls . Some had ingrained dirt , others bent pins , pin scrapes from use or tested low emission , all had different date codes . The 6J52P I was sent that were actually new tested all over the place between 6 and 20mA , even for a high gm type this is poor . I can only make two matched pairs from 30 tubes , microphony also appears to be an issue . On just about all the 6J52 I've seen the internals were crooked . I'm close to giving up on this type ! As well as the D3A , look for some E280F instead , these are much more consistent , test on the money and sound pretty decent . If you have built an amp with 6J52 , these will drop straight in . Running my E280F with unbypassed 75 ohm cathode resistor , 10k load with g2 at 140V .

316a
 
Wished I'd read this before buying from Holms_ua. He is certainly selling used tubes as NOS.

The sides of the glass are strongly emission stained. Several of the 20 tubes in the lot showed 0 transconductance. Out of 20, two tested strong enough to be new, the rest varied from weak to zip.

It cost me almost as much to send them back as I paid for them.

316a, you didn't write on one of the tubes in red marker did you?
 
I tried last year to buy them from a respected seller, but could not agree on a reasonable price I already promised here.
Instead of that I went with 6J51P, which is nice tube, both for drivers and mic pres, Russian version of EF184. They are still undiscovered by audiophiles, and cheap.
 
I thought I would post a warning that there are 6j52p which do not have a cathode connection on pin 1 as shown on the datasheet. I have just found out the hard way with a destroyed shunt regulator. I should,I suppose,have visually inspected the internals or wired both pin 1 and 3.
 
I tried last year to buy them from a respected seller, but could not agree on a reasonable price I already promised here.
Instead of that I went with 6J51P, which is nice tube, both for drivers and mic pres, Russian version of EF184. They are still undiscovered by audiophiles, and cheap.


EF184 still undiscovered by audiophiles? Excuse me, but when I posted about using even EF80's here, people were like "whaaaat??? it's an IF tube!" Anyway, I found some NOS american Sylvanias EF184's here for not too much money, but i didn't think much about them, would you think they 'd be better than the Ultron EF80's I already have, as triode connected? I've read somewhere that they're microphonic, that's why I stayed away. By the way, why nobody ever mentions Ultron, it seems like they were popular as replacements back in the 70's or so...

Thanks!
 
EF184 still undiscovered by audiophiles?

I meant 6J51P. Also, I bought a bunch of 6J9P-E very cheap.

I thought I would post a warning that there are 6j52p which do not have a cathode connection on pin 1 as shown on the datasheet. I have just found out the hard way with a destroyed shunt regulator. I should,I suppose,have visually inspected the internals or wired both pin 1 and 3.

I know there were 2 standards for manufacturers of 6J52P: lower noises for military, and higher power for civil TV sets. I don't know if they manufactured differently, or selected differently, but those in TVs used to die young.
 
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