Preamp Tubes? - Who, What, When, Where, Why, and How? - Page 19

Jesstaa · 06-30-2009, 11:10 PM

You'd honestly think that current production tubes would be of better quality, from all the advances in technology. But all this stuff you're pulling up, Marty, is pushing my want for N.O.S tubes further.

When I get a job and replace the trannys/caps in my amp. I'm gonna buy some N.O.S tubes.

What are the best makes for nice smooth metal overdrive?

Edit: This thread really needs to be stickied. Perfect read for those looking to improve their sound. And I haven't even looked at all the pages.

MartyStrat54 · 07-01-2009, 08:50 PM

Here is yet another link that explains the different tones of 12AX7's and then has (high) pricing for rare and not so rare tubes to salivate over.

Another tube broker:

12AX7 Tubes in Stock

Marty

Jesstaa · 07-01-2009, 09:53 PM

Wow, I can imagine investing in N.O.S tubes would be a good move.

RiverRatt · 07-02-2009, 04:25 AM

OK, bear with me if this rambles. I just put in 19 hours at the office staring at a computer monitor, then I come home and sit in front of this one. Thank God for cheap beer and benzodiazepam. I can't remember the last time I drank Pabst Blue Ribbon, but it has to have been in college. Anyway, since I'll probably be out of it in a half hour or so, I thought I'd share the latest roll. Since I got my newly tested tubes back from Marty, my good ol' RCA side-getters are back in V1 and V2. I've been trying to get V3 and V4 dialed in, but everything I put in there sounded like crap. I had ended up with a Tung-Sol RI 12AX7 in V3 (living on the edge), and some form of Russian 7025 in V4 and I knew the amp should be sounding a lot better than it did - the tone was dominated by this harsh treble sound. Finally it dawned on me... with all this preamp rolling, I'd been neglecting the big boys. I hooked my Sperry up to the test points, and one of my fairly new GTEL34M's was cruising at around 32mV and the other was up around 39mV. I got them back to around 36.5 each, which seems to be the sweet spot, and the magic was back! I'm always telling people if their DSL isn't sounding right, check the bias, and here I go like an idiot, swapping preamp tubes every 5 minutes and wondering why it ain't happening for me. Now I'm good to go until that Tung-Sol craps out, but I think I have 2 or 3 others lying around somewhere. See you guys in a day or two.

joshuaaewallen · 07-02-2009, 02:34 PM

Quote:

Originally Posted by RiverRatt

... I thought I'd share the latest roll. Since I got my newly tested tubes back from Marty, my good ol' RCA side-getters are back in V1 and V2. I've been trying to get V3 and V4 dialed in, but everything I put in there sounded like crap. I had ended up with a Tung-Sol RI 12AX7 in V3 (living on the edge), and some form of Russian 7025 in V4 and I knew the amp should be sounding a lot better than it did - the tone was dominated by this harsh treble sound. Finally it dawned on me... with all this preamp rolling, I'd been neglecting the big boys. I hooked my Sperry up to the test points, and one of my fairly new GTEL34M's was cruising at around 32mV and the other was up around 39mV. I got them back to around 36.5 each, which seems to be the sweet spot, and the magic was back! I'm always telling people if their DSL isn't sounding right, check the bias, and here I go like an idiot, swapping preamp tubes every 5 minutes and wondering why it ain't happening for me. Now I'm good to go until that Tung-Sol craps out...

Power Tube bias definitely effects the tone. For my TSL, Marshall recommends 90mV... I've found a pre-amp combination (thanks to Marty) that I really love, and before moving on to another variation of pre-amp tubes, I decided to experiment a wee bit and see how my power tube bias will effect the sound that I know I already love. Personally, I've found that as good as it sounds when biased as recommended, and having the pre-amp / power amp tube combination that I have, it actually sounds even better when I run it with the bias even lower... say around 85-86mV. I think it's cool how all these seemingly small things have such a noticable effect on my tone.

PS. Let us know how those Tungsols work out for you. I have some currents production Tungsols and haven't used them yet... Not sure where to stick them at this point!

solarburnDSL50 · 07-02-2009, 09:03 PM

Quote:

Originally Posted by joshuaaewallen

Power Tube bias definitely effects the tone. For my TSL, Marshall recommends 90mV... I've found a pre-amp combination (thanks to Marty) that I really love, and before moving on to another variation of pre-amp tubes, I decided to experiment a wee bit and see how my power tube bias will effect the sound that I know I already love. Personally, I've found that as good as it sounds when biased as recommended, and having the pre-amp / power amp tube combination that I have, it actually sounds even better when I run it with the bias even lower... say around 85-86mV. I think it's cool how all these seemingly small things have such a noticable effect on my tone.

PS. Let us know how those Tungsols work out for you. I have some currents production Tungsols and haven't used them yet... Not sure where to stick them at this point!

Plop those Tung Sols in V1 or V2 or both just to see. Then you will prolly go right back to your NOS combo hehe. I like the Tungy's and the Mullard RI's but I can tell the NOS we have are bettering them tone wise to my ears. Playing blues and rock dynamics are really important to me. Not so much when I play metal. Just a wall of pound serves there and the NP's can do. The Chinese 9th generations are good for metal.

That being said I would run those 2 NP I mentioned in V1 or V2 with no worries. I have already. Sound wise I like em' for what I like to play.

RiverRatt · 07-02-2009, 10:38 PM

I like new production tubes in V3 and V4 - the Mullard and Raytheon 12AT7's I have sound great there as well, but the new tubes seem to have a bit more presence or maybe they are a little more aggressive. It's hard to explain. I'm mainly just worried about Marty's info about Tung-Sols failing in V3.

There's a guy on the Les Paul forum who knows his stuff who insists that the PI tube can't have any affect on the tone of the amp. My experience seems to say otherwise. I can hear a difference and feel a different response from the amp with phase inverters that have different gain factors, or even between different makes of the same value.

Josh, I hear what you're saying about the bias setting. I've always thought that the JCM 2000 EL34 amps are biased way too hot at Marshall's recommended setting. Like I said, My DSL50 likes to be around 36-37mV instead of the 45mV that Marshall uses. One of these days I've got to open up my amp and measure the plate voltage. I suspect that 45mV is going to read somewhere between 80-90%.

solarburnDSL50 · 07-02-2009, 11:09 PM

Quote:

Originally Posted by RiverRatt

I like new production tubes in V3 and V4 - the Mullard and Raytheon 12AT7's I have sound great there as well, but the new tubes seem to have a bit more presence or maybe they are a little more aggressive. It's hard to explain. I'm mainly just worried about Marty's info about Tung-Sols failing in V3.

There's a guy on the Les Paul forum who knows his stuff who insists that the PI tube can't have any affect on the tone of the amp. My experience seems to say otherwise. I can hear a difference and feel a different response from the amp with phase inverters that have different gain factors, or even between different makes of the same value.

Josh, I hear what you're saying about the bias setting. I've always thought that the JCM 2000 EL34 amps are biased way too hot at Marshall's recommended setting. Like I said, My DSL50 likes to be around 36-37mV instead of the 45mV that Marshall uses. One of these days I've got to open up my amp and measure the plate voltage. I suspect that 45mV is going to read somewhere between 80-90%.

In order to get a bias of 45mv the PV would have to be at 380 running at 70% dissipation which is hot. My DSL has varied from 450 to 475 PV depending on the power tubes. I run my bias the same as you and even at the higher PV's there is only one number difference in bias. Its between 36 and 38 at 70%. Definitely under the 45mv recommended. If guys like to run em' that hot, burn em' up. I don't.

V1 and V2 have the most effect on tone. I don't hear much of a change from V3 on. On my Night Train you can definitely hear the effect on tone the PI has when changing tubes there.

MartyStrat54 · 07-03-2009, 06:20 PM

Depending on the design of the amp, the PI tube can have an impact on the tone of the amp. Generally, in a Marshall design, the impact is small, but nonetheless, it makes an audible difference. Also, the type of PI tube you use will affect the tone simply by the gain factor of the PI tube used. A lot of Fenders were stock with a 12AT7. I've read articles where people were actually using 12AU7's as a PI in their Marshall amps. If you remember, there was an old timer (no, not me)

who looked for help on this thread. He was having problems with an old Marshall amp. Turns out it had a 12AU7 in the PI. No wonder the amp sounded like a cracker box.

People do weird things in an attempt to find their tone. Like a 12AY7 in V1 and a 12AT7 in V2 and a 12AX7 in V3 and a 12AT7 in V4. I say, if you are doing this you shouldn't be playing a Marshall, maybe not even a Fender. That's just plain whacky, but that's a tube line-up a guy posted online. He claimed it gave incredible smooth tone. (And that was all it could do. Probably wouldn't overdrive if you hooked a Tube Screamer up to it.)

The other thing I wanted to discuss is this situation regarding Tung-Sol. I don't mean to cause a panick, but I am passing on what I have found out and info other members know about. The fact is, once you've tried NOS tubes, it would be really hard to go back using NP, especially in V1 and V2. I mean if I have an RCA 7025 in V1 and a Raytheon BP in V2 and then a couple of sweet tubes for V3 and V4, it would be difficult to say, "Ah the hell with it. I'm going to put Chinese NP tubes in all four positions." I just don't see that happening to anyone that has gotten hooked on using the real McCoy's.

As Joe said, "It's nice having a tube that you know will work in any position." These old NOS tubes just blow away the specs on a new tube and the main thing is they can handle so much more power on the plates. I mean I have looked for over a year for specifications on "any" brand of NP tubes and it just ain't out there.

Well I got all of my tubes in, fourteen in all. Six, Philips-Amperex 12AX7's, four, Philips-Amperex 7025's and four, JAN Sylvania 12AX7's. There were a few bottle rockets, but they all were good, strong tubes. Looking forward to trying some of them JAN's as a V3 and V4 tubes. The way they tested, that would be a good slot for them.

Really anxious to test the P-A 7025's. Two were real stout. Never had them before. If they are anything like the Amperex 12AX7's tone wise, they ought to be a killer V1.

In closing, the same thing applies to NP EL34 tubes. NOS tubes are just flat out better. Some people don't know this, but I post it all of the time. That is, a NOS EL34 can handle plate voltage exceeding 800 volts. I wonder what my Winged =C='s can handle? I'm running one of my 602's with real xf3 Mullards. The other has real RFT EL34's. My TSL122 had Winged =C='s, but I just spent $200 for a set of NOS RFT's for it. It is in the shop, but I left the tubes with them to install.

Have you ever taken a cheap EL34 and held it by the base and tapped it against you open palm? It sounds like a whole bunch of shit is loose in there. A well built EL34 will hardly make a sound if any. Makes you wonder doesn't it? I hear all of these horror stories on the forum were an EL34 turned itself into a ball of flame, or burned up without any warning. When all was said and done, it wasn't anything with the amp. The tube was defective. A NP tube (like a JJ which I'm seeing fail more and more).

I know you can spend 600 dollars or more getting your transformers upgraded. For 300 to 350 dollars (100 watt amp) you can upgrade your power and preamp tubes and you will hear the difference. The difference between the Winged =C='s and the RFT's was huge. Better, tighter bass than before. In the clean channel the amp was almost dead silent and it rang like chimes. In the crunch channel, it was tight and controlled. I was thinking about getting some choke mods done, but after hearing my 602's, I may pass on doing it.

I don't want all my amps sounding the same and I don't think it's possible even if you could make everything equal. I like it that one amp (with certain speakers) sounds a certain way and another amp with different speakers and different pre and power tubes has its own sound. It puts a different smile on your face when you plug in and play.

Marty

solarburnDSL50 · 07-03-2009, 07:51 PM

I need 2 RFT EL34's now. Maybe one of these days... Actually soon I will get my sag back if all works out. If not my shits tight so to speak hehe. I had no idea a choke would take that away from me. I know the difference now because I have had my amp with a choke and without. For what I play I liked it more without the choke. We'll see what my tech can do for me.

Who the heck is charging $600 for an OT upgrade Marty? Mine was $200 installed. Crazy bastids out there...

You made some great tube buys. Some of those power tubes can go up to $350 and more for a set at online dealers.

http://www.kcanostubes.com/products/...tched-Pair.htm

MartyStrat54 · 07-04-2009, 03:22 PM

Joe, I found that info about RFT EL34's and it turned out to be on the forum. However, while it did scare me for a moment, I read the rest of the thread and the real truth was posted by a reputable person.

You have to be very careful using a variac because of those heater voltages, I would highly recommend using a separate filament transformer that is run off the 120V line. You don't want to change the filament supply by more than 10% either way so if you have anywhere between 5.7V and 6.9V you should be alright but if you are out of this range you will drastically reduce the life of your tubes and most likely your tone will suffer. Those RFT's should be able to handle 500V on the plate no problem, the EL34 is rated at 800V on the plate, while alot of new tubes can't really handle this the older ones will and I've had good luck with the new production JJ's which I have run at over 600V without any problems. The problem with going to high on the voltage is not that the tube is run harder its that it will internally short between elements due to the high positive potential. As long as your bias is set correctly a tube run at 500V won't be worked any harder than one at 400V.

-Matt at Triodeelectronics.com

So the bottom line is what I have previously posted and that is a NOS EL34 can handle 800 volts on the plate.

Marty

joshuaaewallen · 07-04-2009, 03:45 PM

Quote:

Originally Posted by MartyStrat54

Joe, I found that info about RFT EL34's and it turned out to be on the forum. However, while it did scare me for a moment, I read the rest of the thread and the real truth was posted by a reputable person.

You have to be very careful using a variac because of those heater voltages, I would highly recommend using a separate filament transformer that is run off the 120V line. You don't want to change the filament supply by more than 10% either way so if you have anywhere between 5.7V and 6.9V you should be alright but if you are out of this range you will drastically reduce the life of your tubes and most likely your tone will suffer. Those RFT's should be able to handle 500V on the plate no problem, the EL34 is rated at 800V on the plate, while alot of new tubes can't really handle this the older ones will and I've had good luck with the new production JJ's which I have run at over 600V without any problems. The problem with going to high on the voltage is not that the tube is run harder its that it will internally short between elements due to the high positive potential. As long as your bias is set correctly a tube run at 500V won't be worked any harder than one at 400V.

-Matt at Triodeelectronics.com

So the bottom line is what I have previously posted and that is a NOS EL34 can handle 800 volts on the plate.

Marty

Quote:

http://www.kcanostubes.com/products/...tched-Pair.htm

... I guess this makes me wonder what, in the long run, those of us who can't afford $400 for a pair of power tubes will wind up having to do? That's half what my entire amp cost me! Know what ah mean, Vern?

MartyStrat54 · 07-04-2009, 06:32 PM

Well the problem is these online tube brokers are just plain crazy on their prices, because they know that someone with the $$$ will buy from them. I can't afford $400 for a quad of power tubes either. That's why I buy on EBAY. Is there more risk? I don't think so, because any time that I've had a problem the seller refunded my money.

What sucks is that back in the 60's and even the 70's, if you had a tube amp, you could buy any brand of tube you wanted cheap. Now all of these special tubes are priced at $80 apiece. I went to that website you posted and looked up the cost on a Raytheon BP. They wanted $80 and were out of stock. So Joe got a great deal from me.

Most of the tubes I buy end up costing me $15 to $24 each. That's a lot cheaper than $40 to $125. The same goes for power tubes. If you really want some nice EL34's, you have to watch several auctions and hope that one of them isn't getting a lot of activity. These are the auctions I like and the one's I make a great deal on. It's just a shame the little buggers wear out, but at least the NOS power tubes last longer than a set of JJ's.

Marty

rockinr0ll · 07-04-2009, 06:34 PM

Marty how do you like Groove Tubes? I have read bad reviews on them but I love them. It turned a really shitty sounding amp into a beast.

MartyStrat54 · 07-04-2009, 06:53 PM

Quote:

Originally Posted by rockinr0ll

Marty how do you like Groove Tubes? I have read bad reviews on them but I love them. It turned a really shitty sounding amp into a beast.

Actually, Groove Tubes in association with their Chinese suppliers have come up with some really nice tubes. I feel they offer the best 6L6 right now. They are noted for supplying some very high gain 12AX7's and I have used them in some of my amps. I know that I prefer them over JJ's and Sovteks.

I'm glad you have had good luck with them, because it all boils down to what sounds good to "you."

I've been using NOS tubes for so long now, it's hard for me to use anything else. As you may have read here in this thread, a lot of current production 12AX7 tubes can't handle the plate voltage of say the phase inverter position. With NOS tubes, you can put them in any position of any amp and they will work. That's a big plus and they sound really good too.

Marty

rockinr0ll · 07-04-2009, 07:03 PM

I love the pre-amp tubes they make. They are called GT-12AX7- "Older style Russian type, strong tone but a little edgy". All of the pre-amp tubes came with a number (mine are 6 or 9 I can't really tell which one it is) but they really sing. I have read that the numbers are rated for style but I think that they just match if you get the numbers right. The Gold Series is the ones that I bought and they sound a lot nicer then the Tung-Sol IMO.

MartyStrat54 · 07-04-2009, 08:06 PM

The numbers refer to what "generation" the tube is. Right now the 9th generation Chinese tube is the best they have to offer. 6, 7 and 8 are still currently being sold as many of these are relabeled by Ruby, Mesa and Groove Tubes.

Right now Tung-Sol is having failure problems in certain amps due to plate voltage exceeding what the tube can handle.

Marty

Petest4 · 07-04-2009, 08:38 PM

Hi...

Anyone ever used soldano 12AX7A in their TSLs? I have some sitting here from my sp77 preamp I sold a while ago.. I believe they are made in China. Worth a try?

solarburnDSL50 · 07-04-2009, 10:01 PM

Quote:

Originally Posted by MartyStrat54

Joe, I found that info about RFT EL34's and it turned out to be on the forum. However, while it did scare me for a moment, I read the rest of the thread and the real truth was posted by a reputable person.

You have to be very careful using a variac because of those heater voltages, I would highly recommend using a separate filament transformer that is run off the 120V line. You don't want to change the filament supply by more than 10% either way so if you have anywhere between 5.7V and 6.9V you should be alright but if you are out of this range you will drastically reduce the life of your tubes and most likely your tone will suffer. Those RFT's should be able to handle 500V on the plate no problem, the EL34 is rated at 800V on the plate, while alot of new tubes can't really handle this the older ones will and I've had good luck with the new production JJ's which I have run at over 600V without any problems. The problem with going to high on the voltage is not that the tube is run harder its that it will internally short between elements due to the high positive potential. As long as your bias is set correctly a tube run at 500V won't be worked any harder than one at 400V.

-Matt at Triodeelectronics.com

So the bottom line is what I have previously posted and that is a NOS EL34 can handle 800 volts on the plate.

Marty

Cool. Thanks for the info. I just woke up. You guys have been busy here.

I pm'd back where I had seen that said about the RFT's. Just wasn't any info to why? Looks like the RFT's are within range of actually buying compared to some of those others...when buying at online dealers. I would do it once on the RFT's just to see. The others are out of my buying zone hehe.

And thanks for the great deals man. I saw that price on the Ratheon BP's and I was like shiat! Some of the other tubes I bought too. I wouldn't have tried them out at those prices. Just would have taken a pass.

solarburnDSL50 · 07-04-2009, 10:14 PM

Quote:

Originally Posted by MartyStrat54

The numbers refer to what "generation" the tube is. Right now the 9th generation Chinese tube is the best they have to offer. 6, 7 and 8 are still currently being sold as many of these are relabeled by Ruby, Mesa and Groove Tubes.

Right now Tung-Sol is having failure problems in certain amps due to plate voltage exceeding what the tube can handle.

Marty

Yep. This on the Chinese tubes. I thought they were decent in my DSL. Alot of the NP preamp tubes I used I didn't have in more than a few months. As far as longevity I can't really say how long they last.

I was recently reading, I can't remember the website, that tubes with gold pins are no better performing than tubes with regular pins. The gold pins just don't tarnish. Anybody know one way or the other on this? Just curious.

Jesstaa · 07-04-2009, 10:53 PM

What are the chinese tubes mentioned under "Trust Your Ears and Ask Your Amp Tech" in this article
What Every Player Should Know about NOS Tubes

MartyStrat54 · 07-04-2009, 11:26 PM

Quote:

Originally Posted by Petest4

Hi...

Anyone ever used soldano 12AX7A in their TSLs? I have some sitting here from my sp77 preamp I sold a while ago.. I believe they are made in China. Worth a try?

If you use any kind of tube amp, then you'll want to hang on to any 12AX7 regardless of where they are made. It's always good to have some spares handy.

Marty

MartyStrat54 · 07-04-2009, 11:45 PM

Here is a site (in German) about RFT EL34 tubes and then it shows all the other tubes they made that were relabeled. There is quite a few of them.

(From one of my wholesalers)
I did indeed receive the tubes without labels or logos (in sealed boxes of 100 pieces each), as they were manufactured for export and eventual rebranding by other tube companies or OEMs. Here is a site (in German) that shows a myriad of relabeled EL34s, all from the RFT plant and identical to the tubes you purchased: Die Geschichte der EL 34 - Seite 4 - in der DDR von RFT produzierte EL34

Marty

joshuaaewallen · 07-05-2009, 12:33 AM

Quote:

Originally Posted by MartyStrat54

Here is a site (in German) about RFT EL34 tubes and then it shows all the other tubes they made that were relabeled... ... Die Geschichte der EL 34 - Seite 4 - in der DDR von RFT produzierte EL34...

Marty

Dude... Where do find all this stuff? Really?! You are amazing! Rock on Marty!!!

MartyStrat54 · 07-05-2009, 05:13 PM

Quote:

Originally Posted by joshuaaewallen

Dude... Where do find all this stuff? Really?! You are amazing! Rock on Marty!!!

Did you click on any of the other links down at the bottom of the page? They show even more relabeled RFT EL34's. One link shows production figures where manufacturing peaked in 1966 and then literally died in 1972. That means most of the RFT EL34's for sale are at least 37 years old and probably older.

One of the reasons I posted this was the fact that there are some brands mentioned that overshadow RFT. Brands like Telefunken, Rohen and Valvo to name a few. If you don't know this info, you could be spending big bucks on a quad of Telefunkens, but they are really RFT's. You aren't gaining any difference in tube tone. The Telefunkens and the RFT's are the same. The difference being price. You can get four RFT's for less than half what a quad of Telefunkens would cost.

I see people get into a frenzy on EBAY all of the time over certain tubes and the bidders are completely clueless. They are making their buying decisions based on brand name and not who actually made the tube.

There is so much tube lore I don't know about, but I wished I did. Things like when RCA decided to turn all of their tube production over to Japan. How many companies made tubes for RCA? I have two Mullards and they are labeled RCA. Who all made black plates and what other companies relabeled them. (One is Baldwin Organ. They used Sylvania gray plates and Raytheon gray and black plates in thousands of organs. Some of these organs contained over 30 12AX7's.) I'd like to know more about JAN and JRC tubes and their connection with the military. Some say they are really great sounding tubes that are very well built (like for combo's). These tubes were made for the military into the 80's. Wow! When did the 12AX7A become an industrial/commercial tube (6681). I think it was 1975.

Yeah, I would like to know all the in's and out's of the tube business. All the secrets that very few people knew about. Which design was the best? What was the biggest seller (and therefore more available now)? It would be sweet to know all of that stuff. It would give you the tools to be the perfect tube buyer.

Marty

MartyStrat54 · 07-05-2009, 08:22 PM

Well, I won another EBAY auction for 12, 12AX7's. One was a NOS/NIB GE and there were three Mullards and some Baldwin/Raytheon and a couple of NEC tubes, one a rare 12AD7 which is like a 7025, but electrically there is some difference. I set a price that I would pay per unit and got it for less than half of that. All 12 were bought for $111.50, or $9.30 each. Ahh, I think I made a good buy. What do you think?

Even though some of them test on the low side of good, this was still a smokin' deal.

Marty

rockinr0ll · 07-05-2009, 08:25 PM

Very nice! I would eventually like to get some of those in my arsenal.

RiverRatt · 07-06-2009, 11:08 AM

I guess I'm going to have to sell a handful of pedals and try to score a pair of RFT EL34's and maybe a RFT 12AX7. I think my GTEL34M's are about to crap out, and all I have in reserve are a pair of Svetlanas and a quad of Sovtek EL34G's. I'd really hoped the GT's would last longer than this, but I'm having trouble with them drifting a lot.
Problem is, my anniversary is next week and the wife is talking about a weekend trip maybe at the end of July, and she just got a new kid-hauler, so my tube purchases keep getting pushed back. Hopefully I've got enough junk lying around that I should be able to swing it. I may throw up some junk, er, treasures in the classifieds soon.

zimske · 07-06-2009, 02:24 PM

woohoo finally!
week worth of waiting and here! they! are!

ruby el34b str (it was a tie between them and tung sols el34b, then doug untied it for me)
tung sol 12ax7
pentalab 12ax7b
sovtek 12ax7lps

can't wait to plug them in my 2203. oh oh.
guys, thanks for everything, will let you know how it works as soon as humanly possible.

[one more thing, however... i've just called my tech and he told me it is not necessary to bias the amp becaus tubes are matched? i've phoned another tech and he told me the same. wtf? EVERYWHERE i've been to read about biasing says that when changing the output tubes, bias is a must. mustly must. wtf with these two techs?. :/]

update: called two more techs which say, of course, bias is a must.
wtf with these four techs?

MartyStrat54 · 07-06-2009, 03:03 PM

Quote:

Originally Posted by zimske

woohoo finally!
week worth of waiting and here! they! are!

ruby el34b str (it was a tie between them and tung sols el34b, then doug untied it for me)
tung sol 12ax7
pentalab 12ax7b
sovtek 12ax7lps

can't wait to plug them in. oh oh.
guys, thanks for everything, will let you know how it works as soon as humanly possible.

[one more thing, however... i've just called my tech and he told me it is not necessary to bias the amp becaus tubes are matched? i've phoned another tech and he told me the same. wtf? EVERYWHERE i've been to read about biasing says that when changing the output tubes, bias is a must. mustly must. wtf with these two techs?. :/]

They're boneheads, I'm sorry to inform you of that.

Yes, the power tubes need to be biased. It's nice that they are matched, that just means that they will bias easier. Why these guys told you that is beyond comprehension, unless they wanted your amp to blow so they would get the work.

Glad you got your tubes. What position were you going to use the Tung-Sol in? Don't use it in V3. They been failing in that position. What amp are these tubes going into? If it has 4 preamp tubes, then use caution with the TS in V3.

Marty

06-30-2009, 11:10 PM	#541 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 1,060	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? You'd honestly think that current production tubes would be of better quality, from all the advances in technology. But all this stuff you're pulling up, Marty, is pushing my want for N.O.S tubes further. When I get a job and replace the trannys/caps in my amp. I'm gonna buy some N.O.S tubes. What are the best makes for nice smooth metal overdrive? Edit: This thread really needs to be stickied. Perfect read for those looking to improve their sound. And I haven't even looked at all the pages. __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) H&S 7 String (Years are over rated) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Chinese 12AX7A Pre: V1 - N.O.S Mullard ECC83. V2 Chinese 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

07-01-2009, 09:53 PM	#543 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 1,060	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Wow, I can imagine investing in N.O.S tubes would be a good move. __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) H&S 7 String (Years are over rated) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Chinese 12AX7A Pre: V1 - N.O.S Mullard ECC83. V2 Chinese 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

07-02-2009, 04:25 AM	#544 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 918	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? OK, bear with me if this rambles. I just put in 19 hours at the office staring at a computer monitor, then I come home and sit in front of this one. Thank God for cheap beer and benzodiazepam. I can't remember the last time I drank Pabst Blue Ribbon, but it has to have been in college. Anyway, since I'll probably be out of it in a half hour or so, I thought I'd share the latest roll. Since I got my newly tested tubes back from Marty, my good ol' RCA side-getters are back in V1 and V2. I've been trying to get V3 and V4 dialed in, but everything I put in there sounded like crap. I had ended up with a Tung-Sol RI 12AX7 in V3 (living on the edge), and some form of Russian 7025 in V4 and I knew the amp should be sounding a lot better than it did - the tone was dominated by this harsh treble sound. Finally it dawned on me... with all this preamp rolling, I'd been neglecting the big boys. I hooked my Sperry up to the test points, and one of my fairly new GTEL34M's was cruising at around 32mV and the other was up around 39mV. I got them back to around 36.5 each, which seems to be the sweet spot, and the magic was back! I'm always telling people if their DSL isn't sounding right, check the bias, and here I go like an idiot, swapping preamp tubes every 5 minutes and wondering why it ain't happening for me. Now I'm good to go until that Tung-Sol craps out, but I think I have 2 or 3 others lying around somewhere. See you guys in a day or two.

07-02-2009, 10:38 PM	#547 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 918	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I like new production tubes in V3 and V4 - the Mullard and Raytheon 12AT7's I have sound great there as well, but the new tubes seem to have a bit more presence or maybe they are a little more aggressive. It's hard to explain. I'm mainly just worried about Marty's info about Tung-Sols failing in V3. There's a guy on the Les Paul forum who knows his stuff who insists that the PI tube can't have any affect on the tone of the amp. My experience seems to say otherwise. I can hear a difference and feel a different response from the amp with phase inverters that have different gain factors, or even between different makes of the same value. Josh, I hear what you're saying about the bias setting. I've always thought that the JCM 2000 EL34 amps are biased way too hot at Marshall's recommended setting. Like I said, My DSL50 likes to be around 36-37mV instead of the 45mV that Marshall uses. One of these days I've got to open up my amp and measure the plate voltage. I suspect that 45mV is going to read somewhere between 80-90%.

07-04-2009, 06:34 PM	#554 (permalink)
rockinr0ll Senior Member Join Date: Feb 2009 Posts: 1,602	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Marty how do you like Groove Tubes? I have read bad reviews on them but I love them. It turned a really shitty sounding amp into a beast.

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07-04-2009, 07:03 PM	#556 (permalink)
rockinr0ll Senior Member Join Date: Feb 2009 Posts: 1,602	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I love the pre-amp tubes they make. They are called GT-12AX7- "Older style Russian type, strong tone but a little edgy". All of the pre-amp tubes came with a number (mine are 6 or 9 I can't really tell which one it is) but they really sing. I have read that the numbers are rated for style but I think that they just match if you get the numbers right. The Gold Series is the ones that I bought and they sound a lot nicer then the Tung-Sol IMO.

07-04-2009, 08:38 PM	#558 (permalink)
Petest4 Junior Member Join Date: Mar 2009 Location: Albury NSW Australia Posts: 6	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Hi... Anyone ever used soldano 12AX7A in their TSLs? I have some sitting here from my sp77 preamp I sold a while ago.. I believe they are made in China. Worth a try? __________________ Cheers PC.. TSL100/1960A/B Valley Arts Guitars ME-70 + GX-700 + stuff...

07-04-2009, 10:53 PM	#561 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 1,060	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? What are the chinese tubes mentioned under "Trust Your Ears and Ask Your Amp Tech" in this article What Every Player Should Know about NOS Tubes __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) H&S 7 String (Years are over rated) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Chinese 12AX7A Pre: V1 - N.O.S Mullard ECC83. V2 Chinese 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

07-05-2009, 08:25 PM	#567 (permalink)
rockinr0ll Senior Member Join Date: Feb 2009 Posts: 1,602	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Very nice! I would eventually like to get some of those in my arsenal.

07-06-2009, 11:08 AM	#568 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 918	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I guess I'm going to have to sell a handful of pedals and try to score a pair of RFT EL34's and maybe a RFT 12AX7. I think my GTEL34M's are about to crap out, and all I have in reserve are a pair of Svetlanas and a quad of Sovtek EL34G's. I'd really hoped the GT's would last longer than this, but I'm having trouble with them drifting a lot. Problem is, my anniversary is next week and the wife is talking about a weekend trip maybe at the end of July, and she just got a new kid-hauler, so my tube purchases keep getting pushed back. Hopefully I've got enough junk lying around that I should be able to swing it. I may throw up some junk, er, treasures in the classifieds soon.

07-06-2009, 02:24 PM	#569 (permalink)
zimske Junior Member Join Date: Mar 2009 Posts: 24	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? woohoo finally! week worth of waiting and here! they! are! ruby el34b str (it was a tie between them and tung sols el34b, then doug untied it for me) tung sol 12ax7 pentalab 12ax7b sovtek 12ax7lps can't wait to plug them in my 2203. oh oh. guys, thanks for everything, will let you know how it works as soon as humanly possible. [one more thing, however... i've just called my tech and he told me it is not necessary to bias the amp becaus tubes are matched? i've phoned another tech and he told me the same. wtf? EVERYWHERE i've been to read about biasing says that when changing the output tubes, bias is a must. mustly must. wtf with these two techs?. :/] update: called two more techs which say, of course, bias is a must. wtf with these four techs? Last edited by zimske; 07-06-2009 at 03:02 PM. Reason: techs wtf!

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