RFT 12Ax7's are they worth the hype

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kmanick

kmanick

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Seems like with a marshall style circuit the old Mullards and these RFT's have quite a fan base.
Do they live up t the hype? In about a week I'm going to start my t8be rolling expedition with my Splawn and I've been thinking about maybe tracking one of these down.
Pete Thorn referred to them in his 12Ax7 shoot out as dark and gainy, which I think may work great in my Splawn.
I do have an old Tungstram 12ax7 in a box but everything else I have in reissue/new.
Mullard
EH
tungsol
JJ
Shuguang (about 20 years old pulled from a couple of old 5150's)
Fender
Sovtek (again about 20 years old)

thoughts?
I generally tend to run my pres and treble down below noon , having a bit of a darker preamp tube may not be a bad thing , I know the JJ's are darker but
I am curious about some of these others.
 
Just my opinion but overrated tonewise and not that reliable ime.

If the Tungsram is like the ones that were in my IIC+ than it should have a noticeably snarly-er high midrange and deeper bass than the RFT.
 
Yeah, they’re good and if youre hunting don’t try to compare to production prices, get em for yourself and cruise on, those prices will probably never go the other way because vintage glass is unique.
 
cool well I just snagged a pair , "Rockon" over on the gear page seems to be a NOS tube dealer and he messaged me with a pair so....
we shall see.
I was just talking to the other guitarist in my band and I sad "watch I'll roll all of these and end up back to with what's in there now" LOL!!
Going to try the JJ EL-34II'
the New Mullard El-34's
and the new EH -EL-34's.
Most likely a 2-3 day 'experiment"
 
incoming :)
IdWI5Xg.jpg
 
Samhain said:
Not the worst but they're no Blackburn Mullard or Amperex Holland.
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To each their own. I find the best pre tube with my 72 Marshall is the vintage Tungsram. Just a killer, screaming midrange and clarity they only provide. Better to me than any of my vintage Mullards, Amperex, RFT, Ei, Chinese, or Tesla pre.
RFTs are very good; to me they add a nice warmth and fatness that is unique. Each amp is different though and like different tubes; my Jubilees loved the Amperex best. Just gotta roll em.
 
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
 
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kmanick said:
Shuguang (about 20 years old pulled from a couple of old 5150's)
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I think those should be Beijing? Does it have square getter? I have a bunch of Peavey labeled ones and like them. If you look between those top two spacers and see clear glass then the tubes haven't been used a ton. That gap between those top 2 spacers gets 'flashed' over time and can be an indicator of how much use it has seen. I have pulled many that have a band of pure silver there.
 
RFT `s are still a good buy. Real mullards are stupid high. Use to buy them for $35 a pop.
 
I’m out of town this week I’ll post some pics of the Chinese tubes when I get back
I have quite a few of them
 
RFT’s are great. However, I have found them to be somewhat fragile.....have had more than a few that were microphonic. But when they are good, they are great!

I’ve recently gone to a NOS Mullard i63 in V1 of my Cherry Bomb, replacing a RFT and LOVE what it did for my tone. Prior, I had an RFT in V1and V2. Also tried a second Mullard i63 in V2 and didn’t care for it at all....made He amp sound like someone cranked the presence.

Full current cocktail:

V1 NOS Mullard Blackburn i63
V2 NOS RFT
V3 Mesa labeled Chines 8th gen
V4 NOS Phillips labeled....not sure what manufacturer

This lineup sounds and feels FANTASTIC in my Cherry Bomb
 
RFT’s are cool,
They are somewhat dark, but yes, have lots of gain, but at the same time, they remain tight.
… but, Tungsram 12AX7s are the bomb! I have completely stopped my search for more nos Mullard 12AX7’s. I have enough to last a lifetime…
 
braintheory said:
So far my 2 favorite preamp tubes have been the Tungsram's and RCA's. The vintage 6N4 can also be very good in the Boogie's and SLO. I liked Tunsgrams best in my Boogie marks, rectos, and JMP2203 and RCA's best in my '89 SLO and '60's Gretsch amp. In my '67 Plexi, Gjika and Schroeder I liked the Tunsgram and RCA's equally well just different flavors. Still gotta try Telefunken, Amperex Bugle Boy, Raytheon and GE's to compare to the my 2 current faves. I have some old Tesla's also that I heard may or may not be RFT's and they sound decent, but I think my Tunsgram's and also Yugo Ei's are much better sounding. I think the RCA's have the most organic, good tone to my ears of all the pre's I currently have, but they can be dark and smooth in some amps, but were the clear winners to me in my SLO and Gretsch and in all my amps would be my choice if I were to prioritize lead tones. It has a real thick, liquid thing for leads
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…try the nos Tungsrams in V1,V2,V3 and V4 of your Wizard MTL bro, it will come ‘alive’.
I can’t believe the difference they made in mine!
…And then while you’re at it, take the JJ 34s out and throw them in the garbage (Or give them away) and replace them with Siemens or Tesla 34s?
 
SQUAREHEAD said:
…try the nos Tungsrams in V1,V2,V3 and V4 of your Wizard MTL bro, it will come ‘alive’.
I can’t believe the difference they made in mine!
…And then while you’re at it, take the JJ 34s out and throw them in the garbage (Or give them away) and replace them with Siemens or Tesla 34s?
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Ah yeah I didn’t get around to testing tubes in that amp yet, but just assumed Tungsram would be the ones since they were in my JMP2203 and Naylor. I have a quad of Siemens actually, but wanted to save them for one of my other amps instead. I haven’t tried as many vintage powertubes yet, but I know the Siemens are good and Sylvania’s I’ve been liking for 6L6’s and RCA for 6V6’s so far
 
So the Mullard and the 2 Tungstrams I have all tested good.
So now I have (all NOS) a Mullard 12ax7, 12ua7, 2 Tungstram 12Ax7 and 2 RFT 12Ax7
Currently my Splawn has
JJEL-34II's (kick ass El-34)
a JJ in V1
RFTs in V2,V3
Stock Chinese 12Ax7 in V4 (PI)
plus I have a few of just about every current 12AX7 there is. (new Mullards, EH, tung-sols, JJ's etc)
How do I maximize this? Normally I'd pop that Mullard in V1 but these heads run a little different.
and I have no Idea what to do with the Tungstrams
I'm thinking maybe
V1:RFT
V2: Mullard
V3:RFT
V4 Tungstram
any Splawn owners that roll these old tubes have any insight?

tube functions of a SuperSport
1. Pre-amp tube - 12AX7 2nd gain stage of the clean channel
2. Pre-amp tube-12AX7 Side A 1st gain stage for clean & OD channels -- Side B 2nd gain stage of OD channel
3. Pre-amp tube-12AX7 Side A 3rd gain stage of OD channel -- Side B 4th gain stage of OD channel
4. Pre-amp tube-12AX7 Phase Inverter
 
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They are to my ears. I have RFT 12ax7's in my Friedman and have used them in other amps too in recent years.
 
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