Is it a real Mullard?

[mdpaudio]

Has anyone ever seen this labeling on a real Mullard 5ar4?

 

[HollowState]

Yes it's real. The base is a little larger diameter then some others. The box is also a tiny bit larger square too.
They also show it in Vacuum Tube Valley.

 

[mdpaudio]

That’s great news! It came in a HK A224 I bought a while back. It alone is worth the price I paid for the amp.
Would you rather use it or a vintage copper 5ar4 in a SE KT88 amp?

 

[HollowState]

Would you rather use it or a vintage copper 5ar4 in a SE KT88 amp?

Damned if I know. They're all pretty much the same to me as long as they're NOS American or European. I don't have or use any Chinese or Russian tubes at all. The Chinese are unreliable and the Russkies are short lived, or so I am told. I do have a few dozen NOS 5AR4s from Amperex, Mullard, RCA, GE, Sylvania (big bottle) and perhaps others. But no metal base "Telles" or super rare types. It's absurd that some of these command such obscene prices that I paid a couple of bucks for thirty years ago. I guess it started when the Asians began buying up all the old tubes they could get their fat little hands on back in the eighties. That's about the time I began saving them up as well. And I'm glad I did.

 

[mdpaudio]

Thankfully I have four 5ar4s from the old days. They are obscenely expensive now. The new ones have let me down several times to the point of using diodes if it doesn’t warrant the expense of a real tube. Sad ain't it?
What do you recommend in 6 volt rectifiers?

 

[sony6060]

Use a UF4007 diode in series with the transformer HV AC output winding (two diodes) before the GZ34 plates. This will about double the PIV rating and then the Sovtek GZ34 performs well with most tube amps. It does not effect the sound either. You must use a fast diode such as the UF4007, not a 1N4007. The Sovtek GZ34 is reliable at lower voltages, just does not tolerate the higher side of voltages in some amplifiers like the vintage Mullard GZ34s.