PX-25 Tubes. Too exotic??


Hi, I'm looking for something different now and am considering the PX-25 tube amps. I current have a 300b tube amp. I really don't see these tubes for sale much anywhere. Strictly talking about tube ease of replacement, cost, variety etc...does anyone have any opinions/experience?

thanx
pawlowski6132
KR Audio, ala Richard Kron, was the first manufacturer to start making the 1920-1965 era PX-25's again. Sophia Electric and Tianjin/TJ (of TJ Mesh Plate 300B 7 45 fame) introduced their own versions in the last couple of years.

The KR & Sophia's are expensive(~$500), while the TJ's are more affordable at $390, but all are readily available.

I've got KR's in my AA PX-25 and they are fantastic. Should get about 1,400-2,000 hours out of them from what Joe Fratus of Art Audio told me. You can get them from any of the high end amp manufacturers of PX-25 amps like Audion, Art Audio(obviously), or Wavelength Audio

Anyway, you should have no problem getting ahold of new PX-25's as long as your wallet is up to the task. If it's NOS Osram PX-25/VR40 you're after - get ready to break out the black American Express card 'cause those will set you back a couple thousand smackers.
I have an Art Audio PX-25 too. I have not compared it to any 300B amps, but love it's sound into my Avantgarde's. I wonder if anyone has compared the current PX's to the NOS models? Just curious (I could never afford them).

Sorry to hijack the thread.

Chris
Hi Chris,

I've also got Welborne Lab DRD 300B monoblocks driving Cain & Cain I-Ben speakers w/ a pair of C&C Bailey subs. The DRD's are one of the most neutral and transparent amps I have ever heard. They are almost "colorless", in that there is no particular tube flavor in the way that makes EL-34 or 300B amps immediately different. For example, I can pick out a Cary 300B amp in heartbeat, but the DRD's don't have ultra-lush midrange. The only thing that marks them as 300B amps is that spooky and magical 300B spatial/ambiance "aura".

By comparison, the Art Audio PX-25's tone is much more vivid or vibrant - as one review reviewer observed "as if instruments were lit from within". Both amps dig deep as far as bass is concerned. High frequencies are equally pleasing and effortless.

The biggest difference between the two that I've noticed is that the PX-25 seems to excel at the leading edge of notes while the DRD's focus on the body of it. The emphasis is slight, but noticable.

The effect is that the PX-25 seems slightly "faster", a bit more more energy, or better attack.

As for NOS PX-25's, they are way outside this kid's budget.
Pawlowski6132,

Are you asking about vintage NOS PX-25's? Osram, Marconi, etc. PX-25 are available from tube collector/dealers, but they start at ~$1,000 a pair and go up up to $2,000 or more(?).

But, as I said in my first post, there are 3 current companies manufacturing PX's right now: KR, Sophia, and TJ. These cost about $500-550 a pair new.

NOS PX-25's can cost just as much as vintage Western Electric 300B's or some really nice vintage 845's. Maybe just a little less. I don't relly know because they are so far out my comfort zone, financially.

If you've got connections in England, it might be possible to find NOS PX-25's cheaper, but then shipping and spec matching becomes a real concern. For the money, all the new production are fantastic.
PX25 (VR40) Globe Shape New in Original Box

Osram make ,made in 1940

dully tested on AVO TUBE TESTER
WITH THE TEST RESULT PRINTED ON EACH TUBES