tubes

[Stonge]

what tubes are everyone using with the markIV?? I don't really have any extra prized tubes sitting around since they are all in my C+. But I am having some shitty sounds come out of this thing (squeeling, feedback, harshness). You know that crappy *** sound you get with cheap *** tubes.I am running all china/russia tubes (mesa new and old). They all tested good..just way to noisy and tinny/grainy than the mullards/siemens. Any reccomendation for good tubes?? I was thinking like some JAN phillips6L6s/Sylvanias for the power and maybe some I don't know..what are some good preamps tubes. I wanted to kind of go the american route since I have all british tubes in the C+. That way I can swith it up for both amps. Thanks in advance for some real solid input. Then again there is always Telefunkens??? LOL!!!

 

[Shep]

jj's in everything but v1. Don't worry about any of that high gain bs. Just standard one's. Then something nice and old for v1. Rca grey plate in mine from around 1950. Was cheap too. $15 a pare.

And the sound is amazing.

 

[212Mavguy]

Hi Stonge,

For the American sound and the quality you crave IMHO you are right on about the sylvania 6l6gc, but they will not be cheap, and you will want to have current draw measured for them in circuit to make sure they are within workable bias range. IMO the MK IV is worth the effort to tube up to the highest quality vintage tubes, it will give back wonderfully.

Mullard and Siemens, preamp tubes, huh? Great for the Euro tones, and I see your dilemma getting an American sound out of your amp with Euro tubes, so for a more American tone I have a few vintage American 12ax7 type recommendations...hard to be more American than RCA 12ax7a shortplate, Raytheon long blackplate halo getter 12ax7a, Tung Sol 12ax7 long grayplate, either rectangular or halo getter, Sylvania short gray or short blackplate 12ax7 (rare and worth finding,) In 5751, I like Tung Sol long grayplate and Raytheon blackplate windmill getter.

There are quite a few others as well that are not yet mentioned, and I 've got a Chimay Ale that says that you will prefer their sound to any modern production equivalents or so called reissues. Search Timbre Wolf's posts for links to his vintage preamp tube reviews, they are informative and excellent. Peace.

 

[trem]

... RCA 12ax7a shortplate...

Does this come with black and gray variation? If yes, which one sounds better? Thanks.

 

[Stonge]

thank you for the info..kick ***. what is a good way to go about figuring out current draw measure?? When I sent my C+ to Mike B, he told me that I could put mullards in the C+(Power amp) without a problem. But I have heard about a good biasing device that folks have talked about that is considerabley cheap and is great for anyone like myself who likes to explore old tubes. Fairly easy to use?? Also how does one go about setting the bias on a mark series?? I am kind of confused - I used to bias my marshalls all the time and that was cake-walk.

 

[trem]

thank you for the info..kick ***. what is a good way to go about figuring out current draw measure?? When I sent my C+ to Mike B, he told me that I could put mullards in the C+(Power amp) without a problem. But I have heard about a good biasing device that folks have talked about that is considerabley cheap and is great for anyone like myself who likes to explore old tubes. Fairly easy to use?? Also how does one go about setting the bias on a mark series?? I am kind of confused - I used to bias my marshalls all the time and that was cake-walk.

The bias on Mark IV isn't adjustable, unless you have it modified. For the bias reader, check this out:

https://taweber.powweb.com/biasrite/br_page.htm

 

[Stonge]

which one would I need w/ the simulclass and all?? the br2 or br4?? also, isn't there some way to control the plate voltage on the markIV?? Or who does the bias mods??

 

[trem]

which one would I need w/ the simulclass and all?? the br2 or br4?? also, isn't there some way to control the plate voltage on the markIV?? Or who does the bias mods??

BR4. BR2 would work also, but you'll have to switch around. If you use "tweed", you'll lower the plate voltage, but that's about the only control the user has on the plate voltage. Look for Stokes for the mod.

 

[212Mavguy]

... RCA 12ax7a shortplate...

Does this come with black and gray variation? If yes, which one sounds better? Thanks.

RCA 12ax7a shortplate is only in gray plate, one of the most underpriced 12ax7's out there. Wonderful sounding tube that lasts huge number of hours in circuit.

 

[Stonge]

I've heard mesa amps are biased so cold anyways...so wouldn't putting any working matched 6L6s in there with any working matched el34s (outer) be fine. I mean there is that slight miliamp difference..but if the tubes are matched together and test good, aren't they then drawing fine??

 

[JOEY B.]

I've heard mesa amps are biased so cold anyways...so wouldn't putting any working matched 6L6s in there with any working matched el34s (outer) be fine. I mean there is that slight miliamp difference..but if the tubes are matched together and test good, aren't they then drawing fine??

Yes and No :? MESA amps are biased cold, but to say that any 6L6 or EL-34 tubes will draw the proper current is a crapshoot.

 

[trem]

RCA 12ax7a shortplate is only in gray plate, one of the most underpriced 12ax7's out there. Wonderful sounding tube that lasts huge number of hours in circuit.

Cool. Thanks Mavguy, but at $90 a pop (KCA), I wouldn't call them underpriced.

 

[6L6C]

which one would I need w/ the simulclass and all?? the br2 or br4?? also, isn't there some way to control the plate voltage on the markIV?? Or who does the bias mods??

Personally I would go for the BR-4 just for convenience alone
As for an adjustable bias I just had it done to my Mark IV although it is working out great for me I don’t recommend it for everybody, the mod is just 1 variable resistor as you can see in the photos below.
Things to keep in mind the outer sockets run a little hotter than the inner so if you get a matched quad and put them in the inner sockets will come up a little cold this is for the 6L6’s.
With the EL34/6L6 things change allot the EL34’s run cold as hell with some Mesa tubes I had the 34’s were coming in at around 5 & 6 watt’s a piece with some from Doug =C= Wings they were coming in around 8 & 9 watt’s.

Why it’s not a perfect world:
Due to the design and room of the Mark IV the bias mod I have adjust all four tubes at the same time, it would be ideal to have one control for the outer sockets and one for the inner, but I don’t. So I can warm up those EL34’s but I’m also warming up the 6L6’s in the inner sockets so everything becomes a balancing act.
Why I did it:
The real reason I decided to do this is so I have the ability to use some NOS tubes, allowing me to fine tune handpicked tubes I already have is just a plus. Is there a huge difference in sound with the bias mod the answer is depends! When using the 6L6/EL34 combination I had pushed the EL34’s up to around 14-15 watts and I found there to be a fairly big difference and it was good , the problem I was pushing the 6L6’s over the cliff. But basically I’m still glad I did it and I’m still new to the experience I have only had it a week so far.

Have thought about having the resistors on the outer sockets changed and get those sockets cooking for the 6L6/EL34 setup but then the amp would have to be dedicated to that configuration and I’m not willing to do that. What might be interesting as you guys with IV’s know we can run 6V6’s but only in tweed since I have adjustable bias now I can probably run them at full power, I just have to look up the specs on the tube first.

 

[Stonge]

well this is something that I definately want done. I don't know whose dick you have to suck to get a decent new tube nowadays...but that is the key NOS tubes. I mean lets face it JJ, Mesa, EH, and groovetube all make garbage that aren't worthy of my Mark IV. I have real mullards in my C+ and that made a HUGE difference. They just sound better and they last forever. This reissue bullshit is in fact that..BULLSHIT. I have tried every tube I can get my hands on and there is just no comparison when you have a 50s-60s mullard in there! I mean I just dropped them (matched) into the C+ without a problem and Mike B assured me that it was fine. Truthfully I just have read tons of posts about this particular subject so many times that I just wanted clarity myself. thanks ya'll..and if anyone knows who does the mod, I am interested.

 

[212Mavguy]

Hey Trem,

It's against my po'boy religion to spend 90 bucks for any preamp tube. :roll:

You can get great used RCA 12ax7a's for like 15 bucks each plus shipping on ebay any day of the week, easy. So you get a few and roll them one at a time in V1 to see how they sound. Their quality is such that I'd be surprised if one out of 5 were not good enough to run in a combo amp. The overwhelming majority of tubes I get on ebay are fine. Peace.

 

[trem]

You can get great used RCA 12ax7a's for like 15 bucks each plus shipping on ebay any day of the week, easy.

Ouch, unlucky me. Just got a pair for an ungodly expensive price of 35 bucks :lol:. Thanks for the tip Mavguy!

 

[Nomad]

NOS Tubes are great no doubt. There are however some current production tubes out there that will get the job done with good tone.

For current production I use JJ and Winged C (real Svetlana).

I also like the loder NOS EI Gold Elite Tubes. They are out of production now though. I have a few of em before they shut the factory down. Greta Tubes.

Ever notice how a Tube Dealer if he dosnt have a brand its crap, but if he has a bunch of it they are great?

All the stuff from New Sensor is crap and all the reissue tubes from them is a freakin ripoff.

GT sucks as well. All the stuff they claim to make, is made in China. They have one process they do in house and thats it. They do not make anything and any Product they have that says Made in America is a lie.

I have had good luck with what Mesa sells but they do sell the crap as well as the good stuff and dont sell some things so choices are limited.

Back to NOS. I have 6 Mullards from 1955 that I purchased from Charly at VTV that are NOS NIB with the originol boxes and all. These things are pristine. Guess what I paid? $150.00 each. They are great sounding tubes. I have heard even earlier Mullards that will make your jaw hit the floor.

Most of the time I have JJ 's and Winged C's in my amps and thats about it. I get very goo tone using that stuff.

As far as Biasing a Simul Amp its just a pain to fit two Pots in there and I just change resistors as needed for warmer Biasing. Rember Boogies are Biased cold but are biased that way for reason. You dont ever want to Bias a Boogie for 60 orm70 Percent Dissapation Rate because it will get noisy and not sound like a Boogie. I do Bias a little warmer than Boogie does but still cold compared to most other amps.

Cold Biasing its part of the Boogie Sound and is what makes them so quite with lots of Gain available in the Amps.

 

[Stonge]

thank you for the info.. I as well am currently using winged C (el34s) and they sound good. I just can't get behind JJs. I am currently trying to find either some jan phillips/sylvania 6l6s. they are expensive, but i have heard nothing but good. Telefunkens?? anyone try these is the mark series yet??

 

[6L6C]

thank you for the info.. I as well am currently using winged C (el34s) and they sound good. I just can't get behind JJs. I am currently trying to find either some jan phillips/sylvania 6l6s. they are expensive, but i have heard nothing but good. Telefunkens?? anyone try these is the mark series yet??

Me too I currently have =C= Wing in the power section and like them allot, not to crazy about the JJ’s either. But in my preamp I do have a JJ in V2 and R2 sounds awesome because of this .
jan phillips/sylvania 6l6s mmmm sounds good to me!

 

[Nomad]

I suppose everyone has their preferences.

I really like the JJ EL34 family over the Winged C's. They have more gerth to them. I really really like the JJ KT77's.

That being said you just cant get a better 6L6 than Winged C. I like them over GE's, RCA's and Sylvania's.

For AX7's I like the JJ ECC83 in high gain positions and the JJ ECC803's in any non sensitive positions.

It's important when getting JJ tubes that you get them from Euro Tubes. Othe sources may not get them in as high a quality as Bob does. Bob has a direct line to the factory.

I have seen high failure rates from JJ's from sources like New Sensor. Dont buy your JJ's from a source like New Sensor or Lord Valve. Its a conflict of interest.