I have heard good things about the RCA 12ax7 tubes in V1. I have a Roadster Head. Do they work good for high gain settings? I have the Doug special, but want to switch out the Tung-Sol. Also, I noticed there are different kinds on Ebay. Are they all the same?
RCA 12ax7
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Anonymous
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I have an RCA 12AX7a in V1 of my Triple and I absolutely love it for high gain stuff. I tried the Tung-Sol reissue I got from Doug's and there's just no comparison. The RCA has a huge amount of power and really makes the amp sound great.
Not too sure about different kinds. I know some are labeled with different brand names, but that doesn't matter.
Not too sure about different kinds. I know some are labeled with different brand names, but that doesn't matter.
212Mavguy
Well-known member
Yesterday i recieved an email from a board member inquiring about a particular RCA auction on eBay. I found it to be an RCA labeled British Tungsram, (I have five of them) then found: RCA labeled RFT, RCA USA long blackplate square getter, RCA USA long grayplate halo getter, and RCA USA short grayplate halo getter. The version that lends itself the most in my experience for guitar amps is the USA made short grayplate halo getter. Amazing sounding tube, dirt cheap, resistant to microphonics and lasts for a looooong time. To my ears it kicks any modern production 12ax7 to the curb. However, different amps sound best with different tubes, but for the money those who have used 'em tend to love 'em.
These five types sound different from each other, some are more resistant to microphonics than others, so I strongly disagree that it doesn't matter which one to choose. The long blackplate square getter is great clean but nasty dirty, and is commonly as microphonic as an old EI long gray or silver plate...ugh! Peace.
These five types sound different from each other, some are more resistant to microphonics than others, so I strongly disagree that it doesn't matter which one to choose. The long blackplate square getter is great clean but nasty dirty, and is commonly as microphonic as an old EI long gray or silver plate...ugh! Peace.
212Mavguy
Well-known member
Hi Shredd,
Yes, RCA labeled RFT means that the buyer will get it for half the going price of properly described RFT 12ax7's, a secret weapon for the old school Marshall sound. :lol: No 12ax7 is more resistant to microphonics in my experience than the fat bottle RFT's. Have a pair of them in Amperex globe orange colored label.
Hi jhguitar1,
The way to tell USA made RCA shortplate 12ax7 is that the mica spacers are chopped off on the sides, parallell to each other. Only RCA did that to my knowledge.
Yes, RCA labeled RFT means that the buyer will get it for half the going price of properly described RFT 12ax7's, a secret weapon for the old school Marshall sound. :lol: No 12ax7 is more resistant to microphonics in my experience than the fat bottle RFT's. Have a pair of them in Amperex globe orange colored label.
Hi jhguitar1,
The way to tell USA made RCA shortplate 12ax7 is that the mica spacers are chopped off on the sides, parallell to each other. Only RCA did that to my knowledge.
dodger916
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Yes. Mullard Blackburns are code 1022; Raytheons are 280; I can't read the code on my RCA 5751 triple mica black plate (very sweet tube). I'm not sure what the Herleen, Holland factory code is (Amperex, Bugle Boy), but the production codes also indicate that. Here's a great website for identifying many vintage preamp tubes by the production code:jhguitar1 said:
http://www.tube-classics.de/TC/Tubes/Valvo/Phlipscode.htm
Lou
Well-known member
So based on this thread I got a few RCA's on eBay.
Ps. I tried to insure I wasn't on the same items as poster here was going for.
I'll post close ups when I get them
also whilst at it I came across a 59 Mullard D Getter El84 and since I have two new RI in my 22 that I love, I figured to give it a whirl.
anyway these are the ones I got....
I bid on a bunch but as I was not able to be around at the close of bidding I had to bed on many and hope for the best
1958 Mullard D Getter 6BQ5 Electronic Tube
New 1959 RCA Triple Mica Black Plate JRC 5751 / 12AX7 Electronic Tube
1962 Mullard 7025 / 12AX7 Electronic Tube
thoughts from those in the know?
Ps. I tried to insure I wasn't on the same items as poster here was going for.
I'll post close ups when I get them
also whilst at it I came across a 59 Mullard D Getter El84 and since I have two new RI in my 22 that I love, I figured to give it a whirl.
anyway these are the ones I got....
I bid on a bunch but as I was not able to be around at the close of bidding I had to bed on many and hope for the best
1958 Mullard D Getter 6BQ5 Electronic Tube
New 1959 RCA Triple Mica Black Plate JRC 5751 / 12AX7 Electronic Tube
1962 Mullard 7025 / 12AX7 Electronic Tube
thoughts from those in the know?
MusicManJP6
Well-known member
I was the one that contacted the very knowledgeable mavguy212 about the RCA tubes I found and he came back and suggested some short plate halo getters instead. I ended up scoring them and they should be here this week. I'll update on the difference ASAP! I'm new to the NOS tube thing so it should be an eye opener if all the talk about them is true. I've tried some modern tubes and not been that impressed when comparing them to my stock Mesa tubes.
MusicManJP6 said:
I'm with you bro ! I'm new with the NOS or "Slightly Used" tubes as well.
Just made my first "vintage" tube purchases this weekend. I'm eagerly awaiting a RCA 12AX7A short gray plate halo getter, a RFT 12AX7, and a GE 12AX7 17mm long gray plate. They should be in this week
Dom
shredd6 said:domct203 said:Just made my first "vintage" tube purchases this weekend. I'm eagerly awaiting a RCA 12AX7A short gray plate halo getter, a RFT 12AX7, and a GE 12AX7 17mm long gray plate. They should be in this week
Dom
Holy freakin' CRAP!! You're not messin' around are you!
Yea, I'm pretty stoked as you can imagine. Next tube I'm looking for is a box plate Mullard 12AX7, and then maybe a vintage Tung-sol 5751 and/or Mullard 12AT7.
Dom
MusicManJP6
Well-known member
shredd6 said:domct203 said:Just made my first "vintage" tube purchases this weekend. I'm eagerly awaiting a RCA 12AX7A short gray plate halo getter, a RFT 12AX7, and a GE 12AX7 17mm long gray plate. They should be in this week
Dom
Holy freakin' CRAP!! You're not messin' around are you!
I wish I could be there when you guys fire up your amps for the first time with these tubes in them.. It's always cool when someone doesn't know what to expect, then they hear it. Just the looks on their faces.. Total amazement.
It never gets old to me.
I'm stoked as well (also for you, Dom)! I'll be sure to have a camera on hand to capture my 'face of total amazement'. Haha. I just got a pair of RCA 12ax7a's to start with. I haven't gone all out yet like Dom.
Should be fun though! If all goes well then i'll be in the market for some others. More to come later...
lyman
Well-known member
domct203 said:shredd6 said:domct203 said:Just made my first "vintage" tube purchases this weekend. I'm eagerly awaiting a RCA 12AX7A short gray plate halo getter, a RFT 12AX7, and a GE 12AX7 17mm long gray plate. They should be in this week
Dom
Holy freakin' CRAP!! You're not messin' around are you!
Yea, I'm pretty stoked as you can imagine. Next tube I'm looking for is a box plate Mullard 12AX7, and then maybe a vintage Tung-sol 5751 and/or Mullard 12AT7.
Dom
i got a mullard 12at7 for my phase inverter recently. so far so good. you can find them for good prices still. i never tried the tung-sol, but you might want to look into the JAN Phillips 5751 too. nice smooth sound, and not too hard to come by. i put mine in the first position for my maverick's lead channel and it took away the harshness.
dodger916
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+1 on the Mullard 12AT7WA in the phase inverter. I got one with balanced triodes from Doug's Tubes. Made a big difference in my IIC+.lyman said:
dodger916
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Yes! That's the new Mullard 12AT7WA (balanced triodes) I was referring to.shredd6 said:
Thanks for the tip on the Mullards Shredd6 !
The RCA & (Tesla) RFT are here, I hope the GE is here for tomorrow (rehersal).
Dom
The RCA & (Tesla) RFT are here, I hope the GE is here for tomorrow (rehersal).
Dom
212Mavguy
Well-known member
Hi Shredd,
When solid state stuff was killing off the tube manufacturors one by one, they had to scramble and outsource to meet their product demands, what you have are most likely RCA's relabeled. Take a hard look at the plates, the shape of the tabs poking through the micas, the getter halo shape and support, and all that kind of thing. Silkscreening means nothing, so to speak, the structure determines the sound and I bet that when you roll the tubes you have displayed in your post that there will be some resemblance in tonal characteristics. I've seen Mullard labeled RFT... I own some National, made in India 12ax7's that have the basic Mullard shortplate build style and tone...because they were made on Mullard tooling just like the Matsushitas were. Dirt cheap, too!
Tooling can and has been moved to different countries. Look how much stuff you buy today is now made in China, like Celestion speakers...I have some Canadian Marconi 12ax7 shortplates that have the RCA looking plates, but full circle micas, and their tone is virtually identical to the RCA 7025. That RCA 7025 commands a pretty good price these days because it is such a good tube. Another interesting tube with a similar looking plate to the shorplate RCA 12ax7a is the shortplate Raytheon 12ax7a, sometimes seen in Organ labeling (Baldwin), have seen them with made in US labeling as well as the more common "Registered" label, made in Japan. They sound different than the RCA's, more mids.
Interesting on your Westinghouse 12ax7a, I think that the Westinghouse I recently got on ebay is similar to four I got a couple of years earlier, it resembles the Sylvania 12ax7 short grayplate. It had a wonderful full, round fat, but balanced tone. I'm somewhat computer retarded and don't have your awesome image embedding skills, but have often seen Westinghouse labeled long smoothplate tubes that closely resemble older EI long smoothplates made on telefunken tooling, labeled made in Great Britain of all places...As far as etching is concerned, ever see a Raytheon 7729 on ebay with GE style etching on the bottle? I look at the structure inside the bottle to determine the maker more than anything else.
When solid state stuff was killing off the tube manufacturors one by one, they had to scramble and outsource to meet their product demands, what you have are most likely RCA's relabeled. Take a hard look at the plates, the shape of the tabs poking through the micas, the getter halo shape and support, and all that kind of thing. Silkscreening means nothing, so to speak, the structure determines the sound and I bet that when you roll the tubes you have displayed in your post that there will be some resemblance in tonal characteristics. I've seen Mullard labeled RFT... I own some National, made in India 12ax7's that have the basic Mullard shortplate build style and tone...because they were made on Mullard tooling just like the Matsushitas were. Dirt cheap, too!
Tooling can and has been moved to different countries. Look how much stuff you buy today is now made in China, like Celestion speakers...I have some Canadian Marconi 12ax7 shortplates that have the RCA looking plates, but full circle micas, and their tone is virtually identical to the RCA 7025. That RCA 7025 commands a pretty good price these days because it is such a good tube. Another interesting tube with a similar looking plate to the shorplate RCA 12ax7a is the shortplate Raytheon 12ax7a, sometimes seen in Organ labeling (Baldwin), have seen them with made in US labeling as well as the more common "Registered" label, made in Japan. They sound different than the RCA's, more mids.
Interesting on your Westinghouse 12ax7a, I think that the Westinghouse I recently got on ebay is similar to four I got a couple of years earlier, it resembles the Sylvania 12ax7 short grayplate. It had a wonderful full, round fat, but balanced tone. I'm somewhat computer retarded and don't have your awesome image embedding skills, but have often seen Westinghouse labeled long smoothplate tubes that closely resemble older EI long smoothplates made on telefunken tooling, labeled made in Great Britain of all places...As far as etching is concerned, ever see a Raytheon 7729 on ebay with GE style etching on the bottle? I look at the structure inside the bottle to determine the maker more than anything else.
Timbre Wolf
Well-known member
Just to add a twist to this conversation... from my own tube-tastin' I've found that the RCA 12AX7A and 7025 sound quite different from each other, even though they're identical looking inside. Until that listen, I had always thought that they were the same, with the 7025 just being low-noise selected.
Could it be possible that your "Mullard" RCA 12AX7A is not an RCA 7025, and your "Westinghouse" is a true RCA 7025? The Westinghouse re-brand doesn't surprise me much - they shamelessly re-branded everything, and proudly put it in a box that stated "you can be sure if its Westinghouse" They didn't etch like Philips tube codes - it is more of a baked-on ceramic ink - so they probably added it after purchasing batches from RCA.
- Thom
Could it be possible that your "Mullard" RCA 12AX7A is not an RCA 7025, and your "Westinghouse" is a true RCA 7025? The Westinghouse re-brand doesn't surprise me much - they shamelessly re-branded everything, and proudly put it in a box that stated "you can be sure if its Westinghouse" They didn't etch like Philips tube codes - it is more of a baked-on ceramic ink - so they probably added it after purchasing batches from RCA.
- Thom
212Mavguy
Well-known member
FWIW, a true 7025 is supposed to have a spiral wound heater filament to reduce hum.
+1 on the Westinghouse relabeling, the same goes for Zenith. However, the Westinghouse 300b is Westinghouse made, very spendy, and a holy grail tube for HIFI.
+1 on the Westinghouse relabeling, the same goes for Zenith. However, the Westinghouse 300b is Westinghouse made, very spendy, and a holy grail tube for HIFI.
MusicManJP6
Well-known member
Hey guys! Although I can't add anything to the enlightening tube relabeling discussion I CAN add something about the RCA tubes the original poster inquired about. I finally got my RCA 12AX7A tubes installed and boy were they worth the price! I had a chance to give them a run this weekend at a jam session and they really made my Rectoverb come to life! The tone was fine before (or so I thought). After playing through the clean channel with the stock tubes I swapped out the stock V1 for an RCA and flicked her on and could tell a difference right away. Swapped them out again and listened to the distortion with stock in place and then with the RCA in V1 and yep, much better with it in! The second RCA I received resides in V2 for now although the difference was not nearly as pronounced here as when I swapped out the V1 tube.
I'm very happy with these tubes and will be shopping for more in the near future! I would like to thank mavguy212 for guiding me in my tube purchasing! He's got all kinds of tube knowledge in that head of his... You the man, mavguy!
(BTW, I think some Mullards or Tung-Sols are in order for my next tube purchase)
I'm very happy with these tubes and will be shopping for more in the near future! I would like to thank mavguy212 for guiding me in my tube purchasing! He's got all kinds of tube knowledge in that head of his... You the man, mavguy!
(BTW, I think some Mullards or Tung-Sols are in order for my next tube purchase)
