Preamp Tubes? - Who, What, When, Where, Why, and How?

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MartyStrat54

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Does the tube you have in the reverb position (V4 in my amp) have any bearing on the tone if you don't use any reverb?

It doesn't seem like it to me but just wondering.

No. In this instance the 12AX7 is being used as a driver, not as an amplifier. You could put a 12AT7 in that slot and probably not notice any difference.
 

RiverRatt

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Remember those Ice Cube sustain couplers they used to sell for Fender reverb amps in the 70's? I wonder if you could do something like that with a Marshall that uses a reverb driver tube? Seems like we gutted one in the shop ages ago and it was just a 270k resistor between the RCA in & out.
 

RiverRatt

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Hey, check out these 12BZ7s. I thought that RCA pretty much made all the tall-bottle twin triode tubes, but I found what appears to be a GE blackplate - it's got an orange RCA logo just like the one on the left, but the GE stencil on the tube name. I wouldn't think there was ever enough demand for a 12BZ7 for two companies to be making them, so the black plate may just be an earlier RCA from a batch they ran for GE, maybe? The plates are similar, but the edges are different.

12bz7.jpg
 

MartyStrat54

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Well the one on the left is a GE. It may have been labeled as an RCA, but it is still a GE. Being a black plate, I would say 1964 or earlier.
 

MartyStrat54

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They are worth about 25 cents a piece wholesale and a couple of bucks for a used 12AU7. Check EBAY. A lot of tube sellers don't even list them anymore.
 

rockinr0ll

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So I should be getting 3 JJ ECC83S matching with balanced triodes for PI. I decided to pay the extra just because I had good luck last time I went with the testing...

Anyone ever try these? I hope they sound better than the Sovtek 12AX7WA-WB and 12AX7WXT+.

It will be an interesting test even though I heard they can be a little dark.
 

RiverRatt

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There are some cool low-watt amp projects that use 12AU7s as power tubes. I've always wanted to build one, but I don't know if I can justify sinking $200 worth of parts into a 1 watt amp.
 

solarburn

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So I should be getting 3 JJ ECC83S matching with balanced triodes for PI. I decided to pay the extra just because I had good luck last time I went with the testing...

Anyone ever try these? I hope they sound better than the Sovtek 12AX7WA-WB and 12AX7WXT+.

It will be an interesting test even though I heard they can be a little dark.

I don't like them in either of my amps but that's exactly what I do with tubes. I try them out and see. Nothing like a real world test for the truest impact.

Bet its fine as a PI.
 

MartyStrat54

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I believe there is a new mini amp that uses a 12AX7 as the gain tube and two 12AU7's as push-pull power tubes. Of course, like the Blackstar 5, there is a lot of solid state going on in the amp as well.
 

solarburn

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Think it was 2 AT7's as the power tubes...

2 watts utilizing 2-12AT7's in a push-pull configuration.
3- 12AX7's
1-5U4
 

MartyStrat54

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Okay, so I go listen to this. What's with the 3 second sound bites? How do you compare the sounds when in 15 seconds, its all over? He then plays out to end the recording...what tube was he using?

This guy wouldn't know a Telefunken from a Sovtek. And the forum he sponsored it on were a bunch of guys who have never heard that much NOS, or else they would "know" the difference.

Now I will say that the guy had a sweet crunch, but how much of that was his tubes? It's not even an all tube amp. When I do a tube test, I generally start with the EQ at midpoint. I remove any scooping and turn the Presence control off. I want the true sound of the tube. Back in my studio in Phoenix, I could get a chainsaw to sound like a Les Paul.

Now I'm not knocking you R'nR. You did good. You posted something that needs to be presented here. However, you have no control over how this guy did his tube test. It all boils down to the 3 second sound bites. All I could tell was that the JJ's were a little quieter and a little darker. The other tubes pretty much sounded the same.

What's amusing is that everyone had a different tube that they thought sounded best. There was no standout winner.
 

thrawn86

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This sounds like a job for MartyMan. You oughta post up something like that for us. Your point of reference would be invaluable.
 

MartyStrat54

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Well there are two things I need to get. A digital mixer/recorder and a digital video camera. I really need to step up into the digital world.
 

MartyStrat54

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SUPER FLASHBACK FROM 5-14-2009-Page 10:rock:

No you're not. I'm of that small percentage of players who crave NOS tubes. Like a story about Marshall's heritage, I feel the same way about a 1962 GE Short Plate as someone would cherish a Plexi. There are some who would say, "He spent $5000 for an all original Plexi. He could have bought himself a new Marshall like a VM or a 410." The same holds true for the need for old tubes. I could by the current stuff, but to me, NOS adds character to your amp.

As far a someone in a crowd recognizing my tone over anyone else's? Ain't gonna happen, because not only can the crowd not sense a players tone, they cannot sense talent. I've seen the worst guitar players get the biggest applause. So that in itself makes the tone issue a moot point.

I told Puffer Fish that as long as I can buy a 12AX7 NOS for $25, that is what I will be running in my amps. From a technical standpoint, NOS tubes can handle a lot more plate voltage. Some of the current preamp tubes are designed right at the voltage operating point. This gives no ground for error. If you get a slight voltage surge, damage could result. Also, I still hold that the quality of materials and coatings used are better than what they are using today. Back when tubes ruled, it was all about making a tube that was better than the competition...spare no costs. Nowadays, it's all about the cost per unit and the bottom line. This formula usually means cheap, cheap, cheap. I mean it is bad when the Tube Store advertises that Sovtek's are no good for combos. To me, that is like saying cheap tube, do not buy. However, what is worse is that one of my 602's came from the factory with two Sovtek WA's in it (V3 and V4) and they are horrible!

I've never met an NOS tube I didn't like. (He-He, that's my Will Rogers imitation.)

There will come a day when NOS will no longer be available. By then, I will be near retirement and I probably will have sold all my gear off. In 2020 how much do you think an RCA 12AX7 will bring?

Some people like to roll tubes and the whole point is to get the best tone with the tubes available. Maybe you have six. Maybe you have sixty. The point is, it's harmless fun. You stick one in and maybe it puts a smile on your face when you palm mute a broken A chord and you can tell the difference over the tube you had pulled out. A while back, I was happy with the NOS tubes in my amp. But because of this forum, I realized that my amps could sound even better. It doesn't matter if anyone else can tell it, it only matters to me. Two tubes changed my whole perception about how my amps could (and should) sound. Now I've replaced tubes in my other amps as well, making sure I have a high gainer in V2 and an 7025 in V1. That is what really makes my TSL's come alive with a super clean channel and crunch-a-bunch.

Now for a while I got a little nuts with tube rolling and was spending too much time on it, but that was because I had a lot of experimenting to do. Now that I've found the formula, I can drop it a notch or two. What I have learned is that NOS tubes have character. (Did I say that already?)

:naughty::naughty::naughty:Marty:lol::lol::lol:

FLASH FORWARD

Obviously the tube rolling hadn't ended...it had just began. I was still thinking that to have an acceptable clean channel, you had to go with a 7025. Hey, we all know that a 7025 is a good tube...for HiFi. Yes, it's a quiet tube and it does enhance the clean channel, but a Telefunken, Mullard or Philips in the V1 slot is the ticket. Isn't it? Yeah, I was pushing that 7025 for quite a while. (Fender loved them in their amps, hence the "Fender Clean" tone.)

It was when I started putting Black Plates in V1 that I said to myself, "That sounds smokin' good." Then I put a 1959 RCA in V1 and it had a great sound. I then put a 1959 Amperex Bugle Boy in there and I thought :wtf:

Of course, in the good old days, I had a 7025 in V1 of my TSL122 and then three short plate GE's in the other slots. I thought this sounded really good. Now I have a Philips Electrohome (made like a Bugle Boy) in V1 and a BP in V2 and two GE short plates. Holy Moly, what a difference.

Hey Joe, what was in that thread you responded to here recently? Something about how two tubes can make a lot of difference in how your amp sounds? Yessir. We all know that here to be fact and if you read the above, you will see that I made that statement a long time ago.

So now all of my amps have made the big change from a 7025 in V1. It's sort of sad, because I did think it was a good formula. However, the 7025 doesn't add anything as it is neutral sounding. Again, perfect for HiFi or the V1 in a Fender amp. We all have are favorite flavor V1's. Mine of course is Philips (and why not go with the biggest...more choices). I'm especially fond of those Holland tubes, but the Canadian version sounds right on (Electrohome). Next would be a Telefunken. I'm with Joe and will go against the grain and say that the ribbed plate just has a little more to offer than the smooth plate. The smooth plate would probably be the better HiFi tube. Then I would have to go to my Mullards. As you can see, my top three are now European tubes. Just six months ago, I was using USA tubes in my amps.

It's all about getting off your duff and making time to play, "Roll, roll, roll your tubes." There is nothing wrong with American tubes. If that is what you are running, consider yourself to be fortunate enough to have them. You could be running Sovteks. However, if you have the tube rolling fever, you will find yourself always pulling V1 out like a chess piece and trying something different.

I have said this before, if it hadn't been for the regulars on this thread, I would have never rolled. I just put in what I thought were good tubes and left it at that. No, the regulars on this forum got me to roll tubes and once I started, I couldn't stop and when you have like 400 tubes, you can do a lot of rolling.

Now I am focused on finding some of the rare 12AX7's that I have mentioned in this thread. Some were only made by NEC during the brief period when the Japanese were making tubes for US companies. However, some of these tubes are more suited to Hi Fi use, because they are basically a superior 7025. However, there are Japanese tubes that were made on Mullard and Philips equipment. These are the one's I have interest in just to see how they stack up and sound.

I also want to get some Miniwatt and some more Valvo's. These are Philips designed tubes and they are very high quality and great for guitar amps.

So in closing on this SUPER FLASHBACK, I stated that I had found the formula, but in reality I didn't. I couldn't get everyone to like what I liked. The truth is, I realized that I didn't like it myself. So this was not an end to tube rolling. We all started rolling more than ever and it became evident that the Black Plate is a great V2 tube, but a European tube in V1 is the real deal.

Now if I can just find a Hi Fi amp to stick all of these 7025's in.

:eek2::eek2::p:applause::p:eek2::eek2:

THANKS TO JOSH FOR STARTING THIS THREAD. PLEASE FEEL FREE TO DROP IN ANYTIME.:)
 
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