Preamp Tubes? - Who, What, When, Where, Why, and How? - Page 6

solarburnDSL50 · 04-25-2009, 02:45 AM

Quote:

Originally Posted by joshuaaewallen

Ok... Normally I try to refrain from profanity in a public forum, but...

Up until recently this thread has had a really great vibe, great information, and plenty of differing opinions coexisting peacefully. But as of late things have started to turn a wee bit sour. Actually downright hostile. Quite frankly, I think we can do better than that. So, without taking sides in any debate that may be going on, I simply would like to ask that a cease-fire be declared, and that we get back to the subject at hand... Sharing info, input, ideas, theories, and whatever with regard to tubes and Marshall amps. That's why this thread was started, so lets keep it that way. Thanks guys!

Amen brother! Lets get on wit the tube talk. Marty gave me some sardines to experiment with. From the 60's.

Anyways over the next couple of days I will try them out in the DSL and give a report. Marty's a good guy!

On a side note I picked up a Vox Night Train for some Voxy blues playing. Its a nice little lunch box. Lots of clean headroom. It has some good overdrive tones too. It is a loud 15 watter. Grant it I have it running through a K100 but it has alot of volume. I already changed out the EH 12AX7's(2)for 2 Tung Sols. I psycho that way. Not much of a difference with that change. Thinking about JJ EL84's now.

Here's a quick question. It is a class A amp. I take it I don't have to bias this thing when I change power tubes? I don't have any info on that yet. End of side note.

PS- My Marshall breathes fire compared to the NT.

joshuaaewallen · 04-25-2009, 08:42 AM

Quote:

Originally Posted by solarburnDSL50

... Marty gave me some sardines to experiment with. From the 60's.

Anyways over the next couple of days I will try them out in the DSL and give a report. Marty's a good guy!

+1 on that one mate. Marty is tops on the forum in my opinion. (How's that for kissin' bum?

) Marty, if you are reading this, seriously, thanks for your generosity and the experience you bring to the forum. Rock on man!

Quote:

Originally Posted by solarburnDSL50

... On a side note I picked up a Vox Night Train for some Voxy blues playing. Its a nice little lunch box. Lots of clean headroom. It has some good overdrive tones too. It is a loud 15 watter. Grant it I have it running through a K100 but it has alot of volume. I already changed out the EH 12AX7's(2)for 2 Tung Sols. I psycho that way. Not much of a difference with that change. Thinking about JJ EL84's now.

On the EL84's I wouldn't know exactly what to recommended, however I do know that there is a lot of difference from one tube to the next. Back when I had my modded Valve Junior there was loads of difference in the EL84's that I tried. Everything from how early it would break up, to significant tonal differences. I'll bet Marty has some insight into this, I know he is an EL84 guy and really is lusting for Marshall to introduce a new EL84 powered monster...

Quote:

Originally Posted by solarburnDSL50

... Here's a quick question. It is a class A amp. I take it I don't have to bias this thing when I change power tubes? I don't have any info on that yet. End of side note.

Sorry mate, no idea.

Quote:

Originally Posted by solarburnDSL50

... PS- My Marshall breathes fire compared to the NT.

The Vox Night Train looks pretty cool. Unfortunately from what I've seen so far, it looks (I haven't had a chance to play one yet) like one of those amps that likely sounds awesome in the hands of the right player, but would not suit my "playing style"*. So far, between, the Vox Night Train, the Orange Tiny Terror (which I have played), and the Marshall Haze... My interest is really peeked by the Haze.
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* When referring to my "playing style", what I mean is that I play most things in what one old timer that I knew called "the key of L". Why? Because as he put it... "It sure sounds like 'ell to me!"

solarburnDSL50 · 04-25-2009, 01:50 PM

Thanks for the input Josh. I know what you mean about tube changes with the valve jr. I had the bitmo mod on mine and boy it sure sounded better with Tung Sol pre's and JJ EL84's. That's why I was wanting to try the JJ's in the NT.

I got the NT for a different take on my blues playing. Its voicing is definitely different from the Marshall's. Its so easy to pack around. I took it over to my buds place and we jammed and it really sat in the mix well. He wanted me to leave it but I have a little more tinkering to do with it before I do.

The main reason I passed on the Haze is I already have that Marshall vibe go'n on. I didn't need a lower watt version of it. Man did Doug Aldrich make that amp sound good in his vid! Love his playing. Besides I really dig my DSL50. So far it has given me everything I need for my playing. Its a keeper.

PS- I'll prolly have a Haze next year...

MartyStrat54 · 04-25-2009, 03:04 PM

Joe, I did a lot of online researching and I couldn't find a thing about the bias question. Now I do know with VOX they sometimes market an amp as Class A when in fact it is a high AB. The Night Train can go from pentode to triode power on the EL84's. This usually means Class A and Class AB operation which means that the power tubes need to be biased. I looked at the owner's manual and it doesn't say a thing. I know nothing about VOX, other than I have played their top of the line stuff like an AC-30. It is possible that the amp is cathode biased and that means you can plug and play the power tubes. You would think the owner's manual would cover a critical topic like this. Did you buy the amp new? If so, maybe the music store knows the question. I have a Traynor all tube Custom 100 that plays in both pentode and triode modes and it must be biased. Better to know before changing out power tubes. I did see where V1 is the gain tube and V2 is the tone stack. It doesn't use a phase inverter, just two 12AX7s and two EL84's. Now that is simple. I looked at it for a while and I would say it is a nice little amp, bigger than a TT. And yes it is nice to be able to carry a 15 watt head up a flight of stairs versus the DSL50. I have an old 1972 Randall 150 watt amp that will break your balls just walking on a level floor. Man that thing is heavy. It makes my DSL401 seem like cotton candy.

Yes, EL84's are sort of like preamp power tubes. They are just a little taller and they have low output. However, depending on who made the tubes can mean a big difference in tone. They all will put out the same power, but the tone can vary wildly. I have three premium sets for my 401. RCA Black Plates,
RCA Gray Plates and Telefunken Gray Plates. In addition, I bought tubes direct from Russia to include premium 1967 Military EL84's. I think I have eight of those left. Of course you know I sold my old 1999 401 and have the cold biased 2006 model. I put a set of these Soviet missiles in my amp and biased them as hot as I could go and they sounded great, almost as much top end as the Telefunkens, but the Soviet's were meatier in the low end.

Well, I hope all is settled here on our tube rolling forum. I'm a hippie from the flower power days. Peace and love.

joshuaaewallen · 04-25-2009, 03:24 PM

Hey Marty... Ya beat me to it. I have been doing online research as well, trying to find out about what biasing procedure (if any) to use on a Night Train... I haven't found squat on the subject.

Like SolarBurn I too had a BitMo modded Valve Junior (although mine had various other mods as well (including a pentode/triode switch)... And fo sho there's major differences in EL84's...

solarburnDSL50 · 04-25-2009, 03:41 PM

Yah guys I haven't been able to either. I joined the Vox forum just to get an answer but have not got a response yet. I'll email proguitarshop.com and see what they say. That's where I bought the amp.

Marty thanx for pointing out the pentode and triode modes as being class A or AB. I missed that. I didn't see anything stating its cathode biased either. It really would be nice to have this info in the manual. I suppose Vox thinks we might hurt ourselves with that kind of info. Nothing a disclaimer can't protect them from. Sheesh!

solarburnDSL50 · 04-25-2009, 03:52 PM

Guys I just got an answer from Vox. The amp is cathode biased so I can plug em' in and play. I wanna try some JJ's first. Fun! Course I'll take any recommendations along the way he he.

MartyStrat54 · 04-25-2009, 04:14 PM

Quote:

Originally Posted by solarburnDSL50

Guys I just got an answer from Vox. The amp is cathode biased so I can plug em' in and play. I wanna try some JJ's first. Fun! Course I'll take any recommendations along the way he he.

Yeah! How's that for an educated guess? I would like to try one of those Night Train heads. What did you give for it, $499.99? That's not bad for a light, 15 watter. I would probably build me a custom half stack with four, Alpha 6 Eminence speakers. (They are the best six-inch speaker I have ever found. Unbelievable lows out of a six and of course great mid's and highs.)

Man, that cathode bias makes tube swapping a snap. All of my Peavey amps are cathode biased. Time to change the 6L6's? Pull 'em and replace 'em.

One note about cathode bias: When changing tubes, the manufacturer is assuming that you are installing a "matched pair" of tubes. Although this type of biasing can handle a small percentage of differences between tubes, it is best to use a set that is matched for best results.

I've been curious about that "Rebel" head with variable power up to twenty watts and can change on the fly between 6V6's and EL84's. That's a neat trick. If I didn't already have about 20 amps, maybe I could justify buying a "small" amp.

Well, it's the weekend. It's great to hear from everyone. I will probably post some more later.

Marty

solarburnDSL50 · 04-25-2009, 05:22 PM

Quote:

Originally Posted by MartyStrat54

Yeah! How's that for an educated guess? I would like to try one of those Night Train heads. What did you give for it, $499.99? That's not bad for a light, 15 watter. I would probably build me a custom half stack with four, Alpha 6 Eminence speakers. (They are the best six-inch speaker I have ever found. Unbelievable lows out of a six and of course great mid's and highs.)

Man, that cathode bias makes tube swapping a snap. All of my Peavey amps are cathode biased. Time to change the 6L6's? Pull 'em and replace 'em.

One note about cathode bias: When changing tubes, the manufacturer is assuming that you are installing a "matched pair" of tubes. Although this type of biasing can handle a small percentage of differences between tubes, it is best to use a set that is matched for best results.

I've been curious about that "Rebel" head with variable power up to twenty watts and can change on the fly between 6V6's and EL84's. That's a neat trick. If I didn't already have about 20 amps, maybe I could justify buying a "small" amp.

Well, it's the weekend. It's great to hear from everyone. I will probably post some more later.

Marty

I will definitely use a matched set. I get tubes from Doug's and he tests them and burns em' in so I should be good to go.

MartyStrat54 · 04-25-2009, 07:34 PM

I sold off most of my EL84's except for the three exotic sets I have and the Russian military EL84's. I will look around and see if I have any extras lying around, but I don't think so. To bad Ei isn't in business anymore. They made the best sounding modern EL84's. Let me know what you think of the JJ's. I think they make more than one type of EL84, but I may be wrong.

Marty

MartyStrat54 · 04-25-2009, 09:45 PM

You know it's funny. I went out and ran some errands and I came back home and decided to go on Ebay and look at 12AX7 tubes. I spent about thirty-five minutes doing this and then I had to start thinking about bidding. I had saved about 12 listings. Well the first batch of RCA black plates started low, but in 40 minutes had went over $140 so I wasn't interested in that. However, next up was a 1956 Sylvania gray plate that tested 129/130!!! Current bid was $11.50. I kid you not. With my trusty pocket watch and a deft move of my index finger, I was the winner at $15.50. (Five bucks to ship which is high, but oh well.)

The point I'm making is that I just won another ICBM for twenty bucks and I wasn't even trying. Ebay has sellers who list all of the new Tung-Sol and Mullard tubes and they want 20 bucks for one of those. Tomorrow, I will be bidding on some black plate Mullards (if they don't go sky high) and a lot of four JRC (Military) black plate 5751's. If they stay low, I'll bid on them, but I usually want 12AX7's. There are some other great deals on a pair of Telefunkens and a quad of Amperex (Holland made) 12AX7's.

I guess if you want to get your hands on some of these you will have to make time to do a little bidding during your time off. I think it's fun to use strategy to ensure a winning bid. My techniques give me around an 80 per cent chance on winning. I can't wait to get this old 1956 Sylvania. I know it's going to be a killer V1 or V2.

Cheers, Marty

solarburnDSL50 · 04-25-2009, 11:47 PM

Quote:

Originally Posted by MartyStrat54

You know it's funny. I went out and ran some errands and I came back home and decided to go on Ebay and look at 12AX7 tubes. I spent about thirty-five minutes doing this and then I had to start thinking about bidding. I had saved about 12 listings. Well the first batch of RCA black plates started low, but in 40 minutes had went over $140 so I wasn't interested in that. However, next up was a 1956 Sylvania gray plate that tested 129/130!!! Current bid was $11.50. I kid you not. With my trusty pocket watch and a deft move of my index finger, I was the winner at $15.50. (Five bucks to ship which is high, but oh well.)

The point I'm making is that I just won another ICBM for twenty bucks and I wasn't even trying. Ebay has sellers who list all of the new Tung-Sol and Mullard tubes and they want 20 bucks for one of those. Tomorrow, I will be bidding on some black plate Mullards (if they don't go sky high) and a lot of four JRC (Military) black plate 5751's. If they stay low, I'll bid on them, but I usually want 12AX7's. There are some other great deals on a pair of Telefunkens and a quad of Amperex (Holland made) 12AX7's.

I guess if you want to get your hands on some of these you will have to make time to do a little bidding during your time off. I think it's fun to use strategy to ensure a winning bid. My techniques give me around an 80 per cent chance on winning. I can't wait to get this old 1956 Sylvania. I know it's going to be a killer V1 or V2.

Cheers, Marty

The Sylvania is from 1956? I can't wait to hear about this one. I can picture you ready to pounce your prey when the tubes are being displayed. You definitely know your tubes man and good job at scoring them. I have never used ebay! Really without a tester I wouldn't just cause I can't tell how good the tube is. Again you have a great set up go'n Marty! I am now learning about NOS tubes. I wasn't even interested before this thread.

solarburnDSL50 · 04-26-2009, 12:05 AM

Quote:

Originally Posted by MartyStrat54

I sold off most of my EL84's except for the three exotic sets I have and the Russian military EL84's. I will look around and see if I have any extras lying around, but I don't think so. To bad Ei isn't in business anymore. They made the best sounding modern EL84's. Let me know what you think of the JJ's. I think they make more than one type of EL84, but I may be wrong.

Marty

I only see one model JJ listed so far as far as the EL84's go. I"ll let you know how they do. Should be here in a week. If you ever do come across something let me know and I would gladly buy them from you too. Keep me in mind. I put the Tung Sol pre's in the NT and I can't really say I heard much if anything different from the EH's that were in it. Will see how changing the power tubes goes.

This one sounds interesting but expensive:

The RFT EL84 tube is a rugged tube that was made in East Germany in the '70's. This EL84 tube is clear and detailed without being bright or etched. The RFT EL84 tends to overdrive easy making it a good choice for hard rock and blues. $65 for a matched pair.

The reissue Gold Lion sounds interesting too but may be to wide to fit in the NT:

Clean tones are chimey and sparkling with single coil pickups and a bit darker with humbuckers. The overdrive on these tubes is smoooth. No gritty, raspy tones, the tubes have just the right amount of compression to track with the overdrive and keep it beautifully controlled while blooming nicely as the note fades out. This produces a very nice organic sustain. "These tubes have a slightly larger diameter than other EL84 tubes so they can not be used in Marshall DSL201 or DSL401 amplifiers, or reissue Vox AC15 amps.

ctc1960 TSL122 · 04-26-2009, 02:27 AM

I also have a TSL122 as well and my reverb has stopped working. Looking at this thread, my guess is that the reveb runs through v4. I have checked all of the connections and they are good. Also, the problem is on and off and usually occurs after the amp has warmed up. There are times when I begin playing the amp and the reverb works for awhile, but then it quits after the amp is nice and warm. Any thoughts?

Thank you, Chris

joshuaaewallen · 04-26-2009, 09:49 AM

Quote:

Originally Posted by solarburnDSL50

... Really without a tester I wouldn't just cause I can't tell how good the tube is. Again you have a great set up go'n Marty! I am now learning about NOS tubes. I wasn't even interested before this thread.

Big time +1 on SolarBurn's comments! Thanks to this thread I am sooooo very interested in NOS tubes, but having no tester I am trepidatious when it comes to buying...

I'm a wee bit bummed... My beloved 12BZ7 that I got from you Marty... Is going bad...

I replaced my power tubes*, re-biased, and discovered exactly where that rattling sound I have lately been hearing through my speakers was coming from... The 12BZ7. Color me sad.
__________________________________________________ _

*I'll post my report on the power tube replacement over on the Yellow Jacket thread as soon as I get a chance. (see below)
__________________________________________________ _

Quote:

Originally Posted by solarburnDSL50

... If you ever do come across something let me know and I would gladly buy them from you too. Keep me in mind.

I'd like to jump on that bandwagon if I could...

Quote:

Originally Posted by joshuaaewallen

... Ok... Here's the scoop...

For those of you that are following the Yellow Jacket / Power Tube saga... click on the little blue arrow next to my name in the above quote...

MartyStrat54 · 04-26-2009, 02:42 PM

Quote:

Originally Posted by solarburnDSL50

I only see one model JJ listed so far as far as the EL84's go. I"ll let you know how they do. Should be here in a week. If you ever do come across something let me know and I would gladly buy them from you too. Keep me in mind. I put the Tung Sol pre's in the NT and I can't really say I heard much if anything different from the EH's that were in it. Will see how changing the power tubes goes.

This one sounds interesting but expensive:

The RFT EL84 tube is a rugged tube that was made in East Germany in the '70's. This EL84 tube is clear and detailed without being bright or etched. The RFT EL84 tends to overdrive easy making it a good choice for hard rock and blues. $65 for a matched pair.

The reissue Gold Lion sounds interesting too but may be to wide to fit in the NT:

Clean tones are chimey and sparkling with single coil pickups and a bit darker with humbuckers. The overdrive on these tubes is smoooth. No gritty, raspy tones, the tubes have just the right amount of compression to track with the overdrive and keep it beautifully controlled while blooming nicely as the note fades out. This produces a very nice organic sustain. "These tubes have a slightly larger diameter than other EL84 tubes so they can not be used in Marshall DSL201 or DSL401 amplifiers, or reissue Vox AC15 amps.

************************************************** ********

Joe: I just sent you an email via your personal email. I looked through more of my tubes and I did find a very rare and exciting set. Check your email for more info. If you are interested in my terms, let me know.

Marty

MartyStrat54 · 04-26-2009, 03:38 PM

I'm a wee bit bummed... My beloved 12BZ7 that I got from you Marty... Is going bad... I replaced my power tubes*, re-biased, and discovered exactly where that rattling sound I have lately been hearing through my speakers was coming from... The 12BZ7. Color me sad.

************************************************** *********
************************************************** *********

I was over at your other place for a while, but thought that I would come over and talk about the BZ7. To me, it seems as if maybe the amp just doesn't like them installed permanently. Some circuits place different voltages on the BZ7 over what an AX7 would see. Since it has less plate resistance, maybe it is getting hotter than it should? However, in all of my old reference materials, a BZ7 is listed as a replacement/substitute for an AX7. Who am I to argue with all of these old books? The AX7 is a lot older tube than a BZ7. I don't think the BZ's were around until the early 60's.

One thing on EBAY that you see a lot. "SOLD AS IS/NO RETURNS." (This gives you a real secure feeling when placing that bid.) I guess I could send you another and if it goes bad, then it goes back to what I said a long time ago with BZ7 #1, "the amp doesn't like them." And I'd hate to see good tubes go bad if it is indeed the amp that is eating them. I'll let you make the call on this one.

Well ole Solar Panel (he-he) is really cooking with fire.

The guy must be a zillionaire going out and getting himself a new lunchbox. I wish I had a little lunchbox like that. I'd stick it full of groovy tubes (no, not those junkie Groove Tubes). I'd make it learn to wail and scream.

I can't wait to hear about it. Little amps like that are perfect to A/B tubes. I mean you have two pre's and two power tubes. Take V1 and change it out, you are going to hear things right away. V2 is the tone stack and a nice tube in there is going to make a big difference. Some nice USA NOS power tubes..."WHAM!"...you can hear the tone of the tubes. Big amps have all sorts of circuits that can disguise the tone of the tubes, but little amps, well they are sort of like a tube tester. They can sort out the good tubes from the bad.

I would love to have a NT just so I could put the ICBM and the BP in the tone stack. Super charge it with some hot American made EL84's and I'd be off to the races. (I still would have to build a 4 by 6 custom speaker cab. That would be "tits!" (As they say in California.)

Well, I'm looking forward to hearing from Joe and I hope it is all good. I don't like bad news, just fun, happy stuff.

solarburnDSL50 · 04-26-2009, 06:48 PM

I'm here guys. Sorry to hear Josh that 1 is a rattler. I just changed out a Penta 12AX7 that had a rattle. It was in the Marshall. Its a Chinese version of a 9th generation Shuguang. It happens. Maybe there's a reason for it like Marty's saying or it just went bad.

Looks like me and Marty are going to be experimenting with the " Lunch Box" a little. Sexy it up with some nice NOS power tubes. Gonna be fun to hear what happens. I'll be mess'n around with some more 12AX7's in the mean time and see what kind of tone changes I hear and feel. I've got some NOS thanx to Marty and some current stock too. They will work in the Marshall and NT. Lots of fun!

I agree the NT hides nothing when you play it. It shows ya whats go'n on and what ain't happening. Its raw and cutting and sits well in the mix with my fellow blues-er. I like it so far and we still got room to tweek.

I think I may get Vox's matching cab when it comes out if I have money he he. It will have a GB in it and I think that would go well with it. The K100 actually sounds good with it as well. I'm glad I had something on hand that was decent to demo these tube changes and hear the NT with.

joshuaaewallen · 04-26-2009, 07:38 PM

I am taking a leap of faith (having no tester), I found a vintage 1955 GE 12BZ7 on eBay that I won, that supposedly tests 103/103. I'll have a go at that and see what happens. One way or another we'll figure out if it's the tube, or if my TSL just eats BZ7's...

MartyStrat54 · 04-26-2009, 07:50 PM

Try to get real used to what the NT sounds like, cuz when it gets shodded with the RCA BP's, I want you to say, "Wow, I really can hear the difference!"

Also, you can stick two USA NOS in V1 and V2 in your DSL and try out the other two in the NT. The Magnavox should be plenty strong for the tone stack in the NT (V2). Plus like you said, you have other 12AX7's as well.

If you lived next door (sheesh!) I would make you a custom cabinet. I have a s**tload of speakers right now and I'm working out a deal with Eminence for my very own speaker that I want to call a V123. As you know, I sent Eminence a couple of old JBL D123's. They did all sorts of tests and they are going to try and replicate that speaker for me. I'll be the only one who can sell it. A D123 has huge bottom end and twice the highs of a regular guitar speaker. If you use effects, it's the only way to rock. Anyway, I see a single D123 in a tuned box with the NT sitting on top of it. That, or the 4 by 6 custom cabinet I keep talking about. (He-he!)

Well, at least I got my new toy (2009 Explorer) to play with and of course the screamin' price I got it for

$875. It has the 500 in the bridge and it will literally torch the front end of my amps. (I don't have any active pickup guitars anymore. Just didn't need what they did...more gain!)

See you later, Joe.

Marty

MartyStrat54 · 04-26-2009, 08:01 PM

Josh, let me know what you want to do regarding the BZ7. I'll send you another, but if it goes bad, you will have to call the experiment off. As I told you, combos are real nasty on tubes, because of the speakers and the heat buildup. The tubes are being vibrated by the sound of music. The BZ7's have long plates and this makes it even worse. As I have said, maybe the BZ7 would work great in a TSL100.

When I sent #1 back to the seller, he ended up sending me a Philco BZ7. Would you like to try that one on for size? Let me know. I think I still have our reusable shipping box.

Talk to you later, Marty.

MartyStrat54 · 04-26-2009, 08:07 PM

Quote:

Originally Posted by joshuaaewallen

I am taking a leap of faith (having no tester), I found a vintage 1955 GE 12BZ7 on eBay that I won, that supposedly tests 103/103. I'll have a go at that and see what happens. One way or another we'll figure out if it's the tube, or if my TSL just eats BZ7's...

So much for my theory that BZ7's were made in the 60's. Well you beat me by one year. I just got that 1956 Sylvania AX7 and now you go and get a 1955 BZ7. I posted on the thread asking what you wanted to do about the BZ7. I have a Philco that you can try if you want. Let me know.

Marty

joshuaaewallen · 04-26-2009, 09:13 PM

Quote:

Originally Posted by MartyStrat54

So much for my theory that BZ7's were made in the 60's. Well you beat me by one year. I just got that 1956 Sylvania AX7 and now you go and get a 1955 BZ7. I posted on the thread asking what you wanted to do about the BZ7. I have a Philco that you can try if you want. Let me know.

Marty

I reckon from the tone standpoint I'd love to try that puppy out... But one at a time... If I burn up two in a row the odds don't seem too good on number three surviving... Let's keep the idea out there and see how it goes... hey... Marty, have you used the 12BZ7's in your TSL combo, or just in heads? Josh = Curious...

So... Tubes with a shortplate design are better in combos?

RiverRatt · 04-26-2009, 09:46 PM

This has been a great week for finding tubes. After reading the posts about EL84s, I went out looking for tubes again today, and added a 6BQ5, a 5U4GB, another 6CG7 and a cool electronics dictionary from the '60s to my collection. The best thing - I have a grand total of $3.29 in this week's acquisitions.

If anyone can help with an ID - I think the 6BQ5 is a Sylvania. Does anyone recognize it?

MartyStrat54 · 04-26-2009, 10:37 PM

Hey, first off I dig the book! That is a nice one and it will come in handy.

If the printing is all gone on the tube look at the etched markings. If it says:

6BQ5
USA
* *
*

Then it is a Sylvania. If it doesn't have the above markings, let me know what the markings are. If the number is in a long octal design, then it is an RCA. Only a few manufacturer's had logos etched in the glass with the printed logos. The print varied from manufacturer to manufacturer. Some would wipe off when new and others could take repeated wipings. The main thing is whether or not the tube is any good? Even if it isn't, the book is worth what you spent.

Marty

MartyStrat54 · 04-26-2009, 11:15 PM

Quote:

Originally Posted by joshuaaewallen

I reckon from the tone standpoint I'd love to try that puppy out... But one at a time... If I burn up two in a row the odds don't seem too good on number three surviving... Let's keep the idea out there and see how it goes... hey... Marty, have you used the 12BZ7's in your TSL combo, or just in heads? Josh = Curious...

So... Tubes with a shortplate design are better in combos?

Yeah, I told you a while back that the shorter plates are more rigid and handle vibration better. The three GE's I "had" in my 122 were short plates.

As I stated earlier, I personally have never used a BZ7, I just knew people who did. I actually bought six of the Westinghouse's on a special buy on the side from a guy I buy tubes from. I had every intention of trying them in an amp. I did research, posted on forums and talked to some other techs. The main thing I learned was a lot of people were in fact using BZ7's in their amps in place of AX7's. I had my TSL100 and 122 already tweaked with NOS tubes and I didn't feel I needed to disturb that, so I thought about trying one in a 602 or my 401, but never got around to doing it. So, I have no real experience at this point with using BZ7's.

Well, I bought my last tubes for a while...I think. Man is it easy to spend money on tubes. I have more tubes than amps and right now. I will be taking out an NOS tube and replacing it with an NOS tube. I think it's safe to turn the burner down for a while. My latest acquisition is a set of four Amperex 12AX7's made in Holland. Also known as "Bugle Boy" on their older tubes. Amperex is rated as one of the best tubes to use in your preamp section. They are right up there in the legends category. Well, I got me four of them and I may just put all of them in my 122 and see how she rolls! How do you like them apples? These ran a little higher than the six Mullards for $69 (what a deal!) These four ran me $83 dollars. Still a good deal when you consider that they are still trying to sell one Ei 12AX7 for $23.50 and "$7.95" to ship. With that in mind, twenty something a tube isn't bad at all.

However, I will test some more and try them out with some early ZZ Top. I will use the 122 as my test amp, since I am suddenly playing it a lot more than in the past (like never). I have been itching to try some of the high octane tubes in one of my 602 amps. I already used the ICBM and the BP in the 401 and it was fantastic. I think what I am going to do is leave the 7025 in V1 and put the hot 1956 Sylvania I bought in V2 in the 401 and have myself a little high gain bandit. It's so much easier to lug around. Well, I did get all of my Mullards tested and marked for I.D. That way I know which one is which. Two of the Mullards were very strong and the other four tested as new. I can't wait to test the Amperex, as the seller uses the same type of tester as I do.

Well, I think there should be a lot of test results on this thread come Wednesday or Thursday. What do you say?

Marty

Seannnn · 04-26-2009, 11:54 PM

hey everyone ... yes i am new to the forum.....it's retubing time for me and i am wondering....i have the DSL 100 JCM 2000.....if i order new preamp tubes will the people know to send me the inverted phase preamp tube with the order or does it matter...are they all the same anyway.....i already know that i want the GTAX7M from Groove Tube......can someone help......hope i don't seem too new to the forum...lol

Seannnn · 04-26-2009, 11:59 PM

ummm that is GT12AX7M's....ooops hehe

solarburnDSL50 · 04-27-2009, 12:03 AM

Quote:

Originally Posted by Seannnn

hey everyone ... yes i am new to the forum.....it's retubing time for me and i am wondering....i have the DSL 100 JCM 2000.....if i order new preamp tubes will the people know to send me the inverted phase preamp tube with the order or does it matter...are they all the same anyway.....i already know that i want the GTAX7M from Groove Tube......can someone help......hope i don't seem too new to the forum...lol

I subscribe to the idea of using a balanced tube for the PI. Others will say it doesn't matter. So if you want a balanced 12AX7 for the PI you just specify one of the preamp tubes to be balanced triodes. There is usually a choice for that when ordering. Otherwise don't worry about it and just order which ever preamp tubes you want to try.

Seannnn · 04-27-2009, 12:11 AM

thanks

04-25-2009, 03:04 PM	#154 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Joe, I did a lot of online researching and I couldn't find a thing about the bias question. Now I do know with VOX they sometimes market an amp as Class A when in fact it is a high AB. The Night Train can go from pentode to triode power on the EL84's. This usually means Class A and Class AB operation which means that the power tubes need to be biased. I looked at the owner's manual and it doesn't say a thing. I know nothing about VOX, other than I have played their top of the line stuff like an AC-30. It is possible that the amp is cathode biased and that means you can plug and play the power tubes. You would think the owner's manual would cover a critical topic like this. Did you buy the amp new? If so, maybe the music store knows the question. I have a Traynor all tube Custom 100 that plays in both pentode and triode modes and it must be biased. Better to know before changing out power tubes. I did see where V1 is the gain tube and V2 is the tone stack. It doesn't use a phase inverter, just two 12AX7s and two EL84's. Now that is simple. I looked at it for a while and I would say it is a nice little amp, bigger than a TT. And yes it is nice to be able to carry a 15 watt head up a flight of stairs versus the DSL50. I have an old 1972 Randall 150 watt amp that will break your balls just walking on a level floor. Man that thing is heavy. It makes my DSL401 seem like cotton candy. Yes, EL84's are sort of like preamp power tubes. They are just a little taller and they have low output. However, depending on who made the tubes can mean a big difference in tone. They all will put out the same power, but the tone can vary wildly. I have three premium sets for my 401. RCA Black Plates, RCA Gray Plates and Telefunken Gray Plates. In addition, I bought tubes direct from Russia to include premium 1967 Military EL84's. I think I have eight of those left. Of course you know I sold my old 1999 401 and have the cold biased 2006 model. I put a set of these Soviet missiles in my amp and biased them as hot as I could go and they sounded great, almost as much top end as the Telefunkens, but the Soviet's were meatier in the low end. Well, I hope all is settled here on our tube rolling forum. I'm a hippie from the flower power days. Peace and love.

04-25-2009, 03:24 PM	#155 (permalink)
joshuaaewallen Senior Member Join Date: Jan 2009 Location: Minnesota Posts: 372	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Hey Marty... Ya beat me to it. I have been doing online research as well, trying to find out about what biasing procedure (if any) to use on a Night Train... I haven't found squat on the subject. Like SolarBurn I too had a BitMo modded Valve Junior (although mine had various other mods as well (including a pentode/triode switch)... And fo sho there's major differences in EL84's... __________________ Josh 2004 PRS Custom 24 10 Top Dean Caddy w/ Bare Knuckles Nail Bombs (This One's For Sale, Just Let Me Know If You Are Interested) 1999 Marshall JCM 2000 TSL 122 - Power Tubes: JJ EL34L's - Assorted New & Vintage pre-amp tubes... I like to roll... HardWire DL-8 Delay/Looper http://irkinempire.spaces.live.com/ "... When you do things right, people won't be sure you've done anything at all." - Futurama

04-25-2009, 07:34 PM	#160 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I sold off most of my EL84's except for the three exotic sets I have and the Russian military EL84's. I will look around and see if I have any extras lying around, but I don't think so. To bad Ei isn't in business anymore. They made the best sounding modern EL84's. Let me know what you think of the JJ's. I think they make more than one type of EL84, but I may be wrong. Marty

04-25-2009, 09:45 PM	#161 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? You know it's funny. I went out and ran some errands and I came back home and decided to go on Ebay and look at 12AX7 tubes. I spent about thirty-five minutes doing this and then I had to start thinking about bidding. I had saved about 12 listings. Well the first batch of RCA black plates started low, but in 40 minutes had went over $140 so I wasn't interested in that. However, next up was a 1956 Sylvania gray plate that tested 129/130!!! Current bid was $11.50. I kid you not. With my trusty pocket watch and a deft move of my index finger, I was the winner at $15.50. (Five bucks to ship which is high, but oh well.) The point I'm making is that I just won another ICBM for twenty bucks and I wasn't even trying. Ebay has sellers who list all of the new Tung-Sol and Mullard tubes and they want 20 bucks for one of those. Tomorrow, I will be bidding on some black plate Mullards (if they don't go sky high) and a lot of four JRC (Military) black plate 5751's. If they stay low, I'll bid on them, but I usually want 12AX7's. There are some other great deals on a pair of Telefunkens and a quad of Amperex (Holland made) 12AX7's. I guess if you want to get your hands on some of these you will have to make time to do a little bidding during your time off. I think it's fun to use strategy to ensure a winning bid. My techniques give me around an 80 per cent chance on winning. I can't wait to get this old 1956 Sylvania. I know it's going to be a killer V1 or V2. Cheers, Marty

04-26-2009, 02:27 AM	#164 (permalink)
ctc1960 TSL122 Junior Member Join Date: Apr 2009 Location: Riverside, California Posts: 21	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I also have a TSL122 as well and my reverb has stopped working. Looking at this thread, my guess is that the reveb runs through v4. I have checked all of the connections and they are good. Also, the problem is on and off and usually occurs after the amp has warmed up. There are times when I begin playing the amp and the reverb works for awhile, but then it quits after the amp is nice and warm. Any thoughts? Thank you, Chris

04-26-2009, 03:38 PM	#167 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I'm a wee bit bummed... My beloved 12BZ7 that I got from you Marty... Is going bad... I replaced my power tubes, re-biased, and discovered exactly where that rattling sound I have lately been hearing through my speakers was coming from... The 12BZ7. Color me sad. *********************************************** ***** ********************************************** ******* I was over at your other place for a while, but thought that I would come over and talk about the BZ7. To me, it seems as if maybe the amp just doesn't like them installed permanently. Some circuits place different voltages on the BZ7 over what an AX7 would see. Since it has less plate resistance, maybe it is getting hotter than it should? However, in all of my old reference materials, a BZ7 is listed as a replacement/substitute for an AX7. Who am I to argue with all of these old books? The AX7 is a lot older tube than a BZ7. I don't think the BZ's were around until the early 60's. One thing on EBAY that you see a lot. "SOLD AS IS/NO RETURNS." (This gives you a real secure feeling when placing that bid.) I guess I could send you another and if it goes bad, then it goes back to what I said a long time ago with BZ7 #1, "the amp doesn't like them." And I'd hate to see good tubes go bad if it is indeed the amp that is eating them. I'll let you make the call on this one. Well ole Solar Panel (he-he) is really cooking with fire.The guy must be a zillionaire going out and getting himself a new lunchbox. I wish I had a little lunchbox like that. I'd stick it full of groovy tubes (no, not those junkie Groove Tubes). I'd make it learn to wail and scream. I can't wait to hear about it. Little amps like that are perfect to A/B tubes. I mean you have two pre's and two power tubes. Take V1 and change it out, you are going to hear things right away. V2 is the tone stack and a nice tube in there is going to make a big difference. Some nice USA NOS power tubes..."WHAM!"...you can hear the tone of the tubes. Big amps have all sorts of circuits that can disguise the tone of the tubes, but little amps, well they are sort of like a tube tester. They can sort out the good tubes from the bad. I would love to have a NT just so I could put the ICBM and the BP in the tone stack. Super charge it with some hot American made EL84's and I'd be off to the races. (I still would have to build a 4 by 6 custom speaker cab. That would be "tits!" (As they say in California.) Well, I'm looking forward to hearing from Joe and I hope it is all good. I don't like bad news, just fun, happy stuff.

04-26-2009, 07:38 PM	#169 (permalink)
joshuaaewallen Senior Member Join Date: Jan 2009 Location: Minnesota Posts: 372	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I am taking a leap of faith (having no tester), I found a vintage 1955 GE 12BZ7 on eBay that I won, that supposedly tests 103/103. I'll have a go at that and see what happens. One way or another we'll figure out if it's the tube, or if my TSL just eats BZ7's... __________________ Josh 2004 PRS Custom 24 10 Top Dean Caddy w/ Bare Knuckles Nail Bombs (This One's For Sale, Just Let Me Know If You Are Interested) 1999 Marshall JCM 2000 TSL 122 - Power Tubes: JJ EL34L's - Assorted New & Vintage pre-amp tubes... I like to roll... HardWire DL-8 Delay/Looper http://irkinempire.spaces.live.com/ "... When you do things right, people won't be sure you've done anything at all." - Futurama

04-26-2009, 07:50 PM	#170 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Try to get real used to what the NT sounds like, cuz when it gets shodded with the RCA BP's, I want you to say, "Wow, I really can hear the difference!" Also, you can stick two USA NOS in V1 and V2 in your DSL and try out the other two in the NT. The Magnavox should be plenty strong for the tone stack in the NT (V2). Plus like you said, you have other 12AX7's as well. If you lived next door (sheesh!) I would make you a custom cabinet. I have a s**tload of speakers right now and I'm working out a deal with Eminence for my very own speaker that I want to call a V123. As you know, I sent Eminence a couple of old JBL D123's. They did all sorts of tests and they are going to try and replicate that speaker for me. I'll be the only one who can sell it. A D123 has huge bottom end and twice the highs of a regular guitar speaker. If you use effects, it's the only way to rock. Anyway, I see a single D123 in a tuned box with the NT sitting on top of it. That, or the 4 by 6 custom cabinet I keep talking about. (He-he!) Well, at least I got my new toy (2009 Explorer) to play with and of course the screamin' price I got it for$875. It has the 500 in the bridge and it will literally torch the front end of my amps. (I don't have any active pickup guitars anymore. Just didn't need what they did...more gain!) See you later, Joe. Marty

04-26-2009, 08:01 PM	#171 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Josh, let me know what you want to do regarding the BZ7. I'll send you another, but if it goes bad, you will have to call the experiment off. As I told you, combos are real nasty on tubes, because of the speakers and the heat buildup. The tubes are being vibrated by the sound of music. The BZ7's have long plates and this makes it even worse. As I have said, maybe the BZ7 would work great in a TSL100. When I sent #1 back to the seller, he ended up sending me a Philco BZ7. Would you like to try that one on for size? Let me know. I think I still have our reusable shipping box. Talk to you later, Marty.

04-26-2009, 09:46 PM	#174 (permalink)
RiverRatt Senior Member Join Date: May 2008 Location: Between Memphis and Nashville Posts: 470	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? This has been a great week for finding tubes. After reading the posts about EL84s, I went out looking for tubes again today, and added a 6BQ5, a 5U4GB, another 6CG7 and a cool electronics dictionary from the '60s to my collection. The best thing - I have a grand total of $3.29 in this week's acquisitions. If anyone can help with an ID - I think the 6BQ5 is a Sylvania. Does anyone recognize it?

04-26-2009, 10:37 PM	#175 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,391	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? Hey, first off I dig the book! That is a nice one and it will come in handy. If the printing is all gone on the tube look at the etched markings. If it says: 6BQ5 USA * * * Then it is a Sylvania. If it doesn't have the above markings, let me know what the markings are. If the number is in a long octal design, then it is an RCA. Only a few manufacturer's had logos etched in the glass with the printed logos. The print varied from manufacturer to manufacturer. Some would wipe off when new and others could take repeated wipings. The main thing is whether or not the tube is any good? Even if it isn't, the book is worth what you spent. Marty

04-26-2009, 11:54 PM	#177 (permalink)
Seannnn Junior Member Join Date: Apr 2009 Posts: 4	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? hey everyone ... yes i am new to the forum.....it's retubing time for me and i am wondering....i have the DSL 100 JCM 2000.....if i order new preamp tubes will the people know to send me the inverted phase preamp tube with the order or does it matter...are they all the same anyway.....i already know that i want the GTAX7M from Groove Tube......can someone help......hope i don't seem too new to the forum...lol

04-26-2009, 11:59 PM	#178 (permalink)
Seannnn Junior Member Join Date: Apr 2009 Posts: 4	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? ummm that is GT12AX7M's....ooops hehe

04-27-2009, 12:11 AM	#180 (permalink)
Seannnn Junior Member Join Date: Apr 2009 Posts: 4	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? thanks

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