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

[RiverRatt]

The plates on my tubes don't have those center holes on either side, otherwise they look like yours.

 

[MartyStrat54]

Well now that's odd. A Japanese tube was either made on Mullard equipment or Philips equipment. I don't know of any Japanese tube company that bought or made their own line equipment. Plus, these are Matsushita's, so you would think they would look like the tube on the left. Now I'm confused.

 

[RiverRatt]

Here's a better shot of the plate on one of the other tubes. Check out the getter flash on this one!! I tried all three in V1 and I wasn't as impressed as I'd hoped. They are similar to my Mullard but a good bit darker. The mids are great, but there's just not a lot of dynamics to them. HOWEVER, I think they may have unseated the Raytheon black plate in V2. With a Telefunken in V1, they make a great combination. I actually caught myself turning the presence up a couple of notches, they are that dark. I wasn't able to really crank them yet, so I'll probably have to go through all this again tomorrow. I have a feeling that they'll sound a lot better at volume.

 

[MartyStrat54]

Man, I would have loved to see that getter flash! It looks like a bomb went off inside of the tube. Well, I think you said your's had a square getter? The older RCA's with square getters are not in as big of demand as an O getter. They tend to be a little darker compared to their O getter version. However, I'm not a tube engineer. I don't know what effect, if any, that a getter has on the way a tube sounds.

 

[RiverRatt]

I'm not really sure how old these tubes are, but I found a thread HERE that gives a few clues - the ones I have look just like the one they are calling a 1958. Also, they are marked as 12AX7s, not 12AX7As, which might support the age estimate. The plates and getter are the same as a late '50s Heerlen Amperex. They've got inked codes on the bottom, but I don't have any reference for them. Looks like:
01
MH

 

[MartyStrat54]

Well that blows my boat out of the water. I didn't think that the Japanese were making tubes in 1958. If they did, it was under close scrutiny. This is due to the pact that was signed after WWII. The Japanese were severely limited to what technologies they could produce.

 

[wegman]

Pardon me for breaking in here but I had a quick question.

Does it mean your tube is on the way out when it looks like this?



Thanks

 

[MartyStrat54]

Pardon me for breaking in here but I had a quick question.

Does it mean your tube is on the way out when it looks like this?

View attachment 1615

Thanks

***Tube 101***

No, not at all. That is getter flash. Usually it is a silver mirror color. What happens it that when they make a tube, they draw a vacuum on the tube. However, they can't get all of the air (gas) out of a tube. What is done after the tube is sealed is the getter is activated. It contains barium and this literally explodes on the glass of the tube. The barium is an active ingredient and it absorbs certain gases. In most cases, the getter works throughout the life of the tube. When a tube gets cracked, or air gets into the tube, it will turn milk white. If you see that, you have a bad tube. There is more to this, but this is the basics.

 

[wegman]

***Tube 101***

No, not at all. That is getter flash. Usually it is a silver mirror color. What happens it that when they make a tube, they draw a vacuum on the tube. However, they can't get all of the air (gas) out of a tube. What is done after the tube is sealed is the getter is activated. It contains barium and this literally explodes on the glass of the tube. The barium is an active ingredient and it absorbs certain gases. In most cases, the getter works throughout the life of the tube. When a tube gets cracked, or air gets into the tube, it will turn milk white. If you see that, you have a bad tube. There is more to this, but this is the basics.

As always thanks for the info Marty, I appreciate it.

 

[RiverRatt]

Pardon me for breaking in here but I had a quick question.

Please break in here anytime you feel like it. A real question always takes precedence over speculating as to the subtle tonal differences between a square or round getter or how many holes your plates have. I'm just trying to learn everything there is to know about Japanese tubes in 10 days or less.

 

[wegman]

Please break in here anytime you feel like it. A real question always takes precedence over speculating as to the subtle tonal differences between a square or round getter or how many holes your plates have. I'm just trying to learn everything there is to know about Japanese tubes in 10 days or less.

Thanks Ratt.

I hate being ignorant and I must admit I am very ignorant on this topic, but I am learning.

I just found a great article that is a huge help. Perhaps it has already been posted but I am posting it again. It is excellent.

http://www.guitaramplifierblueprinting.com/Tubeprimerandselection320-2.pdf

 

[rockinr0ll]

2 questions for you tube rollers!

I have noticed that at high volumes I haven't been getting break up but instead compression? What is up with that?

Anybody ever use the RCA tubes? I have been wanting to get some really nice smooth overdrive tones, are these NOS ones the holy grail?

 

[wegman]

2 questions for you tube rollers!

I have noticed that at high volumes I haven't been getting break up but instead compression? What is up with that?

Anybody ever use the RCA tubes? I have been wanting to get some really nice smooth overdrive tones, are these NOS ones the holy grail?

I have quite a few RCA tubes both the older and newer ones and a couple of black plates and I don't care for the tone of them as much as I do my GE's. Now there are a ton of factors to take into consideration but I find my amp like's GE's in V1 and V2, or they sound better to me then the either of the RCA. I do run a RCA black plate for the PI though.

I am not an expert here by a long shot either.

 

[RiverRatt]

rockinr0ll, I have a couple of RCAs that are sweet tubes, but I don't know if they are necessarily the best tube for my Marshall. They are very smooth with a nice, rounded tone, but I like a tube with a more pronounced midrange. I bought a smooth plate Telefunken off ebay a few months ago and I have yet to find anything I like as much. I have a 1966 Mullard that comes close, but the Tele is just a notch above. Great mids, smooth highs, tight bass - it does it all. I have a black plate Raytheon in V2 and it's a match made in heaven. Maybe solarburn will chime in - he's been doing a lot of rolling with Telefunkens lately.

I'm not sure about the compression. You might have too hot of a tube in V1. I've had power tubes that would sound great up until about 7 and then they would sound really compressed with no dynamics at all, but that was in Fender combos with 6V6s.

 

[SpiritOfTheAge]

Well I think I got one of the Raytheon black plates arriving on Christmas day thanks to some not so subtle hinting to my wife . However I noticed the same seller has these little babies for sale as well, are these the real deal? If so I will sanp one up as a gift to myself

12AX7 TUNG-SOL NOS on eBay (end time 01-Dec-09 10:17:40 GMT)

Ive read on a few websites that the Tung-Sol's are very nice tubes, so if these are the real McCoy im not going to pass one up.

btw I play a DSL 401 and have JAN Phillips in V1 totally love the gain on it, and sounds so good clean as well for V2 and V3 i have a couple of NOS valves that have no name but sound great, and ive just got a JJ in the PI position as i could not tell any difference between ahving that in there and putting the balanced NOS Sylvania i have.

 

[MartyStrat54]

Well I think I got one of the Raytheon black plates arriving on Christmas day thanks to some not so subtle hinting to my wife . However I noticed the same seller has these little babies for sale as well, are these the real deal? If so I will sanp one up as a gift to myself

12AX7 TUNG-SOL NOS on eBay (end time 01-Dec-09 10:17:40 GMT)

Ive read on a few websites that the Tung-Sol's are very nice tubes, so if these are the real McCoy im not going to pass one up.

btw I play a DSL 401 and have JAN Phillips in V1 totally love the gain on it, and sounds so good clean as well for V2 and V3 i have a couple of NOS valves that have no name but sound great, and ive just got a JJ in the PI position as i could not tell any difference between ahving that in there and putting the balanced NOS Sylvania i have.

Yeah it's a real one, but it seems to be pricey to me. You live there so you tell me? If that was a Mullard or a Telefunken, I could see that price. That's about $45 in US dollars isn't it? If you want it, go for it, but if it was me, I would get me an Amperex (Philips), Mullard or Telefunken for V1.

 

[SpiritOfTheAge]

Yeah it's a real one, but it seems to be pricey to me. You live there so you tell me? If that was a Mullard or a Telefunken, I could see that price. That's about $45 in US dollars isn't it? If you want it, go for it, but if it was me, I would get me an Amperex (Philips), Mullard or Telefunken for V1.

Well to find a NOS mullard or Telefunken for that price would be a miracle, I have a used Mullard but im sure its past its best as the Jan Phillips whips it ass tonewise (for me anyways). Of course its pricey though, its Ebay ! I also have a Brimar which is nice, i know i will get a snap of my tubes just for giggles. brb

 

[RiverRatt]

You should be able to find a used Fisher-branded Telefunken easily for that price. As long as it tests strong, it should be a fine tube.

Cool pics, btw. You've got some nice glass there. I've got a Raytheon yellow label 12AT7 that is one of the best sounding tubes I own.

 

[wegman]

Can anyone elaborate on GE tubes.

They sound freaking awesome in my amp in V1 V2 and V3. Better then the RCA's I have/tried. My amp is a JCM 800 2210.

I hear you guys talking about Mullards and Telefunkens and I can't imagine my tone being better then what I have now. I mean I am sure it would be with those tubes but what I have now is pretty close to perfection of what I am going for, and the GE's are the ticket. They sound different from any other tube I have tried.

Anything unique about them or they just happen to be what I like.

Thanks

 

[RiverRatt]

I have some GE tubes that I thought were Sylvania, and I have some Sylvania tubes that I thought were GE. I'm never quite sure which is which. Marty sent me a low-gain GE 7025 that is one of my favorite V1 tubes. It's like the RCAs I was talking about earlier... it doesn't have that same midrange bark that the Mullards and Teles have. It's more of a Fender-y American tone. That's not to say that it's not a fine tube, it just doesn't get me as close to my ideal tone as the European tubes. If I still had a Fender combo, I would probably be all about GE and RCA.

I need to start compiling a database of photos and descriptions of known GE and Sylvania tubes. I've already got an RCA database started. It really comes in handy when you're trying to figure out what you have, especially when the writing is gone. If you haven't been to tubemongerlib.com, check it out sometime. It's a pictoral database of NOS tubes.