RFT 12Ax7's are they worth the hype

  • Thread starter Thread starter kmanick
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I think Tungsram is the best tube of the ones you have...

I use in a Marshall jose:
V1: tungsram
V2: Chinese 12ax7
V3: Sovtek LPS

As for the sovtek...it f slayed the nos ei smooth plate as well as a Telefunken long plate...
The best PI tube...
 
JJ's are darker but to me , kind of lifeless almost dull sounding
If you are talking ecc83s then yeah, there's not much h application for them with the exception of PI position. And there they shined in my Yeti, made a huge difference in tone too for some reason, added complexity and top end sparkle compared to the Tad and chinese I had before. Not sure why, and It wasn't on purpose, but fantastic result. Never tried a sovtek LPS in there, but I really have no need to atm. Nice find for such a bashed tube
 
You'll have to roll them. Just because it's a NOS Mullard/Tungsram or whatever doesn't insure it will sound great in that spot AND be low noise and low microphonics.

The best way to hear what each tube brings is to put it in V2 (in that amp) and listen to both channels, especially the OD channel. You'll probably hear the snarly mids and full bandwidth of the Tungsram vs an RFT...but which do you like better in that amp? I would also gently tap on each tube with a chopstick to listen for microphonics. I suggest doing this at a decent volume (so you can check for good singing feedback and hear noise better) and take breaks often. Your ears get fatigued and then your are just spinning your wheels.

If that new production Mullard is a long plate I'd prob stick that in the PI (it looks almost identical to Sovtek LPS and made in same factory). And I'd expect a good NOS Mullard to be 1st candidate for V2. You probably will still hear a difference between a Tungsram and an RFT in V3.
 
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Tungsram in V1,V2 and RFT in V3,V4 of my C+ amps with Sylvania 6L6 or 6L6/6CA7 combo power tubes. The RFT helps tame the brightness in the lead channel, while the Tungsram keeps the clean channel very clear.
 
I have gone with
V1: Mullard
V2: RFT
V3:RFT
V4: Chinese
this combo sounds nice and fat and throaty but still open. I tried a Sovtek LPS in the PI and actually liked it but it killed some of the "juice'
I have a gig this Friday and this is what I'll roll with but I may try the Tungstram in the PI now . the V1-3 spots are all set.
 
I've put RFT's in amps that are naturally bright and could use some thickening up.
My EVH, Mark V:25 and Savage 60 all have them in V1. For my Invader 100 I'm actually looking for something brighter and more aggressive than the Tungsol that's in V1 now.
 
I've put RFT's in amps that are naturally bright and could use some thickening up.
My EVH, Mark V:25 and Savage 60 all have them in V1. For my Invader 100 I'm actually looking for something brighter and more aggressive than the Tungsol that's in V1 now.
the tungstrams are bright but without needless "sizzle" try one of those, it might do the trick.
 
so if you look above (see post #26) you can see what I've got in my Supersport. it's been sounding great , no complaints going on 2 years now with this set up.
BUT :)
I just got an Amperex holland 12ax7 in today and I'm wondering which spot it would have the most effect in to maybe smooth out
the upper mids a bit?
 
so if you look above (see post #26) you can see what I've got in my Supersport. it's been sounding great , no complaints going on 2 years now with this set up.
BUT :)
I just got an Amperex holland 12ax7 in today and I'm wondering which spot it would have the most effect in to maybe smooth out
the upper mids a bit?
I feel the V1 has the biggest impact in most amps I’ve owned. PI spot would be #2.
 
I would say no. In a modern amp pretty much anything is fine. Though modern preamp tubes are priced pretty high nowadays, moght as well get some nos Mullards.
 
I would say no. In a modern amp pretty much anything is fine. Though modern preamp tubes are priced pretty high nowadays, moght as well get some nos Mullards.
the tubes I have in there are all NOS as is the Amperex
 
so if you look above (see post #26) you can see what I've got in my Supersport. it's been sounding great , no complaints going on 2 years now with this set up.
BUT :)
I just got an Amperex holland 12ax7 in today and I'm wondering which spot it would have the most effect in to maybe smooth out
the upper mids a bit?

RFTs are already fairly dark. I would try V1 and then Whichever position is feeding the tone stack.

My personal fave combo is Beijing 6N4-J in V1, RFT in V3 and other gain-stage positions, and then Sovtek LPS in PI. I haven't tried Amperex though.
 
Mo
I'm hoping the Tungstram that I already have and one or both of these RFT's will tame the brightness of this thing a bit
and fatten it up. It already sounds awesome as is with a JJ in V1 and Chinese the rest of the way but I find the Chinese 12AX7's
brittle sounding, granted they are quite Gainy and reliable, but in the past I always pulled them. I've just left them in the Splawn since I got it
because the amp sounds so good. Now a few gigs later, I'm thinking I want to warm it up a bit. JJ's are darker but to me , kind of lifeless almost dull sounding , inV1 it works well in this amp because that's the clean driver, but I may try a Tung sol in there or a Mullard and see what that does to the clean
Move the JJ's to V2 & V3. I go with a Tungsol in V1. If you want fatter, try a current production Mullard CV4004 in V1. But those JJ's in V2 & V3 will tame any brittle/grainy tone. Those Chinese tubes are likely the culprit. Especially if they are lower end, cheap ones.
 
I love RFT's

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