EL34 vs EL34B Difference?

[dwinstonwood]

Hello,
I've been trying to Google and answer to this with little luck. I did find this statement:
"They are a slightly higher impedance tube which means they will bias differently that a regular EL34."
The reason is, I'm ordering the tubes for my SSE (I finally bought the Edcor transformers - this has been a five-year build project) and I've been reading good reviews of the new Tung-Sol EL34Bs.
Would I need to change R17 and R27 to use EL34Bs?
Or, I can always just go with regular EL34s, too. How are the new Mullards?
Thank you in advance.
David

 

[JonSnell Electronic]

I think you will find EL34 is the original copyright title from Mullard and other manufacturers back in the day when production was good and EL34B is the new build version.
EL34s as NOS cost an arm and a leg and EL34Bs from China/Eastern Block, are relatively cheap.

They are basically similar in performance.

 

[dwinstonwood]

Thanks JonSnell.
I'm new to all of this. I'm realizing that I'll actually have to finish the amp and take measurements to know anything. While I'm waiting for my Edcor order I need to get a chassis/enclosure lined up. I went ahead and ordered a Sovtek 5A4R, a Tung-Sol 12AT7, and two Tung-Sol EL34B's. My OPT's are the Edcor GXSE15-5K's and the primary is the Edcor XPWR035. Thanks.

 

[waxx]

They are indeed equivalents. The modern ones can sound very good. The better Shuguang EL-34B's (like those used in Prima Luna amps) are as good as most NOS EL34's if you ask me, and the Psvane and Gold Lion are in the same league also, but more expensive. Those Tung-Sol are not bad at all, but not up to the others mentioned.

 

[dwinstonwood]

Thanks waxx. These must be the ones you're talking about. They're not outrageously priced... maybe down the road at some point I'll try them:
PrimaLuna EL34 – Upscale Audio
David

 

[waxx]

Thanks waxx. These must be the ones you're talking about. They're not outrageously priced... maybe down the road at some point I'll try them:
PrimaLuna EL34 – Upscale Audio
David

Those are indeed the by Prima Luna selected, tested and rebranded EL34B's made by Shuguang that i use. I have an older PL (Prologue 4) amp, and tested it with many tubes (also 6L6's, 6550's, KT77's and KT88's), but at the end i now use back the stock tubes, as they are the the best sounding in that amp.