'58 RCA long black plate 12AX7 quad for my Fisher

Midrange/bass lite?

 

That makes since.

 

That's maen.

 

NOS tube hunting is fun.

Years ago I bought a 1967 Blackface Pro Reverb guitar amp, many years later the RCA 12AX7 went down in the Vibrato channel so I pulled the one from the normal channel but found it micro phonic. Then I remembered that when I bought the amp, the seller gave me a bag that had a half a dozen boxes with tubes in them. 4 were NOS RCA 12AX7's. Sweet!

Years later, I bought a large diameter condenser mic for recording vocals. It came with a modern Chinese tube in it. I did a little research and bought Amperex and Telefunken NOS tubes. They both sound great and the top end harshness was tamed and it really gave the mids a smooth presence and enhanced the low end. The mic sounds very different and you would think it much more expensive.

It's still not a Neumann, but a friend who has a U87 really likes my mic and bought one with the same NOS tubes I got. He likes how it records certain singers that aren't a good fit for the U87.

In any case, I highly encourage anyone with tube audio great to get some quality NOS tubes. They can take a good sounding amp from good to great!

 

Is this sarcasm? I thought you loved black plates!

 

RCA long blackplates are utterly fantastic in V1 of Fender amps.

The surprise was doing a shootout of about 15 NOS tubes in my Marshall (all 12AX7s) and my Blackburn Mullard sounding very good but the grey plate RCA absolutely KILLING it and so easily, too. With the RCA, everything sounds 3D, sounds ridiculously nice. Putting the Mullard back in makes my Marshalls sound like tin cans in comparison.

Nobody was more surprised than I considering I've always read how Mullards kicked major butt. The RCA made minced meat of the Mullard. I wouldn't have thought it possible without hearing it for myself. Both in my SuperLead and my JTM45.

 

In my experience, if you have the money, you can get some. I know of a source that can get pretty much anything you want but you'll pay through the nose.

I had to draw the line somewhere so I never went all out with, say, XF2 Mullards in my SuperLead which would be enough to pay for more than a mortgage payment on my house.

 

Yeah, Fender black face and silver face are famously lean and scooped in the midrange and play very clean and the RCA black plate 12ax7's give 'em a hint of fatness and girth that's really appealing in those amps. But in my experience they sound wooly and kinda bloatedly fat an overwarm in the bass and lower midrange in any kind of hifi circuit that calls for neutral tonal balance and full audible range bandwitdth (neither of which come into play with guitar amps where you're deliberately creating the tone color of your preference and you're not reproducing the bottom two octaves nor the top two octaves.

I do like Mullards though in guitar amps too circuits because they have jangle and sparkle if that's what you're looking for in your guitar sound (although they're not that janglely in hifi circuits).

And like @Steve Hoffman , I've had a lot of problems with RCA black plates 12ax7s going noisy on me relatively quickly.

 

Going noisy relatively quickly compared to what? I have had a pair going on 10 years that have seen duty an an old Vox and my Fisher 500c, they're now back in the Vox. I wouldn't expect them to last as long as say a Mullard or a Tele but they last way longer than any new production tube I've used. They are definitely the fattest, warmest sounding tube I've heard but some really like that. I grabbed another pair because they're just plain fun to use once in awhile

 

Compared to almost every other twin triode preamp tube I've ever had except for maybe some of those OEM Groove Tube 12ax7M's. Really remarkable how many of 'em I had start out not noisy and become noisy. By contrast I have a bunch of Sylvania black plate 12ax7s that I've been using for years in all kinds of different applications and they've all be solid as a rock. Now it's a small sample of maybe 10, 12 tubes and mostly pulls over the years. But still...it was a pretty consistent experience for me with those tubes.

 

That's interesting. Ive never heard anyone complain about NOS RCA going microphonic at an unusually high rate. I like their EL84s so hopefully not that same problem.

Sylvania black plates are some of my favorites in both 12ax7 and EL84. Let's not talk about those too much.

 

One thing I like about tubes is the surprise factor. Over a month ago I bought a pair of NOS Hitachi 12AX7 for my Phono preamp, just as a test, an experiment, for fun. They've turned out to be outstanding at least for me, I love how they sound. I like their bass which is tight and controlled and not boomy at all, their detailed yet silky mids and treble, they are dead quiet despite having long plates, they have good gain and they're not microphonic at all. I know saying one has a pair of Hitachi tubes on his Phono preamp doesn't sound like much, they are not highly regarded as RCA's, Telefunken's or Mullard's, but they sound great for me anyway. They had a fair price but knowing how they sound as I do I'd have paid double for them, I love them. Here's a pic of them.
Now that I know how they sound and how much I I like them I've been looking for a spare pair (I expect the Hitachi's to last long) but I haven't found any NOS pair, but I found these, which of course I bought.
I know they're not the same as the Hitachi's I'm currently using but they don't have to be worse. It was all a surprise to find them and even more surprising nobody bidded for them so I bought them for a good price, 70 $ for the 4 tubes, a bargain. These are branded after a joint venture between Hitachi and Raytheon but they were 100% made by Hitachi. I hope they are as good as my current Hitachi's and I wouldn't mind if they are as good as them but in their own and different way, so when I get them in about two weeks and test them, SURPRISE!
Does anybody have any experience with Japanese tubes? I'm tempted to buy a pair of NOS Matsushita 12AX7.

 

As mentioned in your early thread they are very nicely made tubes and still a steal. I'd love to know your thoughts on the Hit-Ray tubes. I've heard decent things about them and am a fan of Hitachi tubes and Raytheon black plates are my favorite.

Matsushita Tubes are always a good deal. Sound nice, quiet, and last way longer than new production. I retubed my Fisher recently with all Matsushita. Figured I would save my Mullards and Teles for other endeavors. I'll probably take some hits for this comment but i think they give about 90+ percent what you get with the Mullards. They are a touch less warm and have what I would describe as a bit grainer sound.

 

I can't wait to get those Hit Ray tubes, I'm eager to check how they sound on my humble and cheap Chinese Yaqin MS-23B Phono preamp.
I'm happy to find another fan of Japanese tubes, Hitachi's in particular, they were all a revelation to me, I love how those little glassy things sound.
Don't worry, as soon as I get the Hit Ray tubes I'll post a comment about them after some hours of warming up and listenning.
Wish me luck with the Hit Ray tubes!

 

Just got my pair of RCA black plates from this guy. They've only been playing for a couple of hours but they sound as warm and gooey (in a good way) as I remember my other pair. I think I might actually leave this pair in and box up the Matsushitas they replaced and probably grab another pair while I'm at it. I'll definitely run them through the fall. They're a great fall/winter sounding tube.

Thanks for the tip.

 

Wow, that's really drilling down on it!

 

Doest it mean they are hot or cool ?

 

Love RCA tubes... phenominal value

 

They are a fun tube to roll in but I don't know if I'd want that sound all the time, but I'm definitely digging them right now.

 

I regretted not buying another set of 12AX7's as backups from the same seller (they were probably all sold to folks on this forum, heh heh).

Today I see that he offered more of the same, but rated slightly lower (60-74 vs. 80-90 for new), so I scooped up the last three he had. $20/each.

I'm really enjoying the first set of '58 RCA long plates in my Fisher.

 

I bought four from this seller thanks to you. I have blackplates from sixties but there's something special about the ones from the fifties. I use a combination of tube makes in my two Fishers but these four blackplates in my Harman Kardon A500 Integrated amp are perfect.

 

So these 12ax7 RCA tubes seem to be the opposite of the RCA 12au7 Cleartops? Which sounded bright and trebly to me.