[Creed]

Hi, I bought a kt 120 amp with 4 6922 and 2 12ax7 front end tubes. 12ax7’s are the more crucial tube.

I’m familiar with the 6922 tube and have a stash of amprex, Valvo and so on. Not so much on 12ax7’s. I bought some used Mullard 60’s Blackburn, Telefunken’s and RCA long black plate.

I like the Mullard and rca but not sure yet on Telefunken need more time with it.I’m wondering if anybody is familiar with the Tungsram friend had same amp as me and  said it was his favorite in the amp. Tungsram is Hungarian and so is the amp, maybe it’s voiced with the amp.. Also curious about the Mazda tube or any other tube. Any help or insight would be appreciated.

[FullRangeMan]

What Telefunkens do you bought? The 1920 Telefunken vintage factory or the new 2005 Telefunken factory?

[Creed]

Earlly 60’s, has a lot of air very tranparent maybe light in bass. It may need a little run in time. I’ve only left it in the amp an hour or so. Have mostly spent time with rca I really like that tube. Mullard sounds close to rca but little darker.. Amp is class A so bass is big and fast but little less on Tele. I’m questing the 12ax7’s I have are more common, curious about others.

[FullRangeMan]

The Telefunken 1960 are great tubes.
Avoid the 2005 Telefunken US tubes that are just rebranded tubes and the Telefunken brand are licensed.

[Mike B.]

The Bugle Boy's are nice sounding. Tele smooth plate is another favorite.

[Creed]

Thanks Mike I’m running the tele smooth plates right now. I buy these tube through a reputable dealer I’ve been using for years. These are used to keep cost down but test high. I’ve always wondered if they have been sitting up for years do they need a little break in time or need a certain amount of time to settle in, hours days?

[FullRangeMan]

I’ve always wondered if they have been sitting up for years do they need a little break in time or need a certain amount of time to settle in, hours days?
After 6 months cold the getter start goes to sleep, after years inactive to reactivate the getter a few heating and cooling cycles will be required, which will start cleaning the internal gases, which should improve the sound after some time.

[Mike B.]

I think a couple heat cycles would be the maximum if any " settling In " is needed.

[rpf]

I like the RCA (or Raytheon) black plates and old Mullards a lot. Which is better depends on the amp and position, of course. Don't like Telefunkens in my amp: too bright.
Found the Tungrams to be good but less so than my preferred tubes: in both 12AX7 and 12AU7s, I found them rather thick sounding.

[thorman]

 Best I have ever used was the Ge 5751 3 Mica Black plate...Superb Tube. Best balanced of all 12ax Types to my ears. A little less Gain, but well worth it .

[FullRangeMan]

Best I have ever used was the Ge 5751 3 Mica Black plate...Superb Tube. Best balanced of all 12ax Types to my ears. A little less Gain, but well worth it .

Thanks I will take note on this.

[gene9p]

I like the Jan Ge 5751's too..but at this moment my Mac c2300 is using Genalex Gold Lions with gold pins...best all around performance tube that plays nice with everything from Jazz to Rock.

[Creed]

Gene9p, I was shocked how nice that gold lion is, have to agree on the gold lion gold pin. Sounds more like the Tele than rca and Mullard I have. Out of the 4 12ax7’s I have I like the rca black plates. If I could find something to beat the rca that would be fun. Thanks for all the suggestions.

[rpf]

The Gold Lions are good but the GE long plate 12AX7s from the '50s and early 60's are better. Very similar sounding to the Gold Lions but smoother up top.

[FullRangeMan]

7025 also a good 12ax7 substitute.

[Freo-1]

Telefunken 12AX7 is my favorite. 


Strong dislike for the Russian/Chinese 12AX7's.  Spend the $$$ and get real NOS tubes.

[Escott1377]

The Telefunken smooth plates are really good.  Mazda silver plates are the best that I have heard but they are pricey and often hard to find. 

[FullRangeMan]

Telefunken 12AX7 is my favorite.

What Telefunken?
The NOS 1960 or the new rebranded 2005 ?

[Audiosaurusrex]

Telefunken ECC83 Smooth-Plate has 19mm long plates and considered one of the best 12AX7/ECC83 tubes ever made IMO

[Freo-1]

What Telefunken?
The NOS 1960 or the new rebranded 2005 ?

NOS, of Course!