The Preferred Series 7025 is a great sounding 12AX7 tube type that reminds me a little more of the ECC83 that EI made in the old days. That’s a pretty nice compliment. I compared this tube against an old EI and Telefunken smooth plate and there was very little difference. Lots of gain with a rather low noise floor. No microphonics issues at all. Very good considering the large plate size. Spot welding may be better for microphonics than crimped plates. I tried it in all the standard guitar amp duties and it was fine. Fabulous in Blackface Fender amps. We tried this 7025 in a 66 Vibrolux reverb 2×10 combo and the tones were all there. Light and shimmering or really aggressive, it’s all good.

I have a quick question. I have recently replaced the three preamp tubes (matched Preferred Series 7025) in my Hughes&Kettner Deluxe 36. After the replacement, when I first turned on the amplifier, the second preamp tube had an orange colored burst glow for a second. However, all three preamps are working fine.
Is there a reason why the new preamp tube had this short duration glow burst during the first run? Thanks in advance.
This is perfectly acceptable. Many preamp tubes do this when first powered from a cold state. Not all will of course, but it is not a sign of a problem.
I have a question. I just purchased my very 1st tube amp. It’s a Blues JR. IV. The literature that came with it says it has 3 preamp & 2 power tubes. Listed like so…Preamp 3-7025/12AX7A/ECC83. Output 2-EL84/6BQ5. My question is are these 5 different types of tubes? I need to learn what I am using, so that I may better use it. Can u please advise?
OK so the 7025/12AX7A/ECC83 are all one in the same… think of it like English, French, and Spanish where each type is just a different “word” meaning the same thing. Same goes for the reference to EL84/6BQ5. So you have 3 12AX7 types and 2 matched EL84 tubes in that amplifier.
You guys won’t like what I am about to write. Tube rolling.
Why can’t manufacturers make tube amps sound good so that it cuts out tube rolling.
Impossible you say. Wrong.
The only person (purchase his amp)
That does this is lim from affordable valve company. (Now disappeared).
Had his amp for three years with no problems and no tube rolling.
When music was played, it was has if the singer was in the room not coming out the speakers, those who have a good hifi will know what I mean.
Tube rolling only makes the manufacturers richer.
And like repeats, repeats, repeats on TV they think the public is dumb.