Mark IV Tubes - A few short questions...

[visualrocker69]

JUST KIDDING!!!
There's a lot of questions
Sorry, but I really need the help and greatly appreciate it!

I have a Mark IV coming soon. Used, but only for less than a year, and 100% mint condition!

The problem is since the previous owner has been using it for about a year, I ever might or might not have to change tubes, depending on how heavily he used it.

So a few questions regarding tubes… starting with some basic ones.

1) How do I know when I need to change the tubes? Any objective indications? I’ve never owned a tube amp before, so it’s not like I can just “hear” that the tubes sound worn out and need replaced…

2) Do you guys generally let your tubes die or replace them, uh, preemptively?

3) Basic question: Can you simply buy compatible tubes from ANY maker and put them into a Mark IV, or are there any adjustments that need to be made?

4) I read on the sticky that using GT tubes with a 4-7 rating will not void warranty. So, it follows that any other non-Mesa tube WILL void warranty? And what exactly is a 4-7 rating anyway?

5) Besides Mesa and Doug’s Tubes, what are some preferred retailers? Sources for NOS would be greatly appreciated to!
(Are Sylvania 6L6’s available anywhere? Or Mullard EL-34 Don’t worry, I won’t tell a soul… :wink: )



And now for some SPECIFIC tube questions…

Due to the board’s feedback on my previous question posts, I’ve resolved to keep the default Mesa tubes.

After some time, however, I’ll want to try different ones, so I might as well start deciding now.

By the way… the Mark IV can ONLY use four 6L6 or two 6L6 & EL-34 (outer) pairs for full functionality, right? I read something about other tubes, but then its limited to Tweed/Class A or something… Are 12AX7 the only preamp tubes it can use? I’ve read something about people using 6V6’s, 12A-something else…12AT7? 12AC7? What’s the deal with that?


6) Anyway, I’m trying to decide between two configurations…
SED 6L6GC/EL34 with Tung Sol 12AX7A’s in the preamp section…
…or simply four GT 6L6-GE with GT12AX7-M’s.

Those are both good, yes? How would the EL-34’s effect my tone, though?
A few of you (Guitarzan, Platypus, etc) swear by Groove Tubes. How would this four 6L6 configuration compare to four SED 6L6GC’s?

Does anyone have any corrections or alternate recommendations regarding those tube groupings I’ve chosen so far?
(Before anyone says JJ’s, I heard that they’re better for brighter/fizzier amps, and tend to suck a lot of the tone from the Mark IV, especially in the preamp section…)

I’m actually not sure about the preamp tubes at all… just picked up on the GT Mullard reissue’s from something boogiebabies said earlier…

Dunno about the Tung-Sol’s 12AX7 if I decide to go with SED 6L6 & El34 though. Is there something better? Boogiebabies says Tung-Sol’s are all marketing hype.

7) I’ve heard that V1 is by far the most important tube as far as determining sound, and the others can be viewed as “support tubes”. Is this the case? If so, would it be sufficient to put a more expensive tube in V1 and leave the rest as more affordable (but still reliable) tubes, or am I misunderstanding things?

And finally, some more technical questions… keep in mind I know NOTHING about tubes, unfortunately.

8 ) I know that Mesa utilizes fixed biasing, so their amps don’t need to be adjusted for different tubes, right?… but I don’t even know what biasing is to begin with!!! Can anyone give me an extremely condensed and un-technical explanation please?

I’m also unsure about what the term “matching” refers to, in the context of tubes.

9) I came across something about different colors on identical Mesa tubes… something about different idle amounts… what’s that all about?



Well that covers almost everything. So here comes the grande finale!
A clump of vague, unsorted questions



10) As far as tubes go, any other favorites?

What do you guys think of Sovtek, Shuguang, Penta Labs, Ruby, Svetlana… etc?

I’ve read Russ’s recommendation for Telefunken, Mullard, RCA, RFT, Mazda gray plates, Amperex, Bugle Boy, Brimar, Tungsram, Tesla…
So many names! Some of these seem like classics, as I’ve seen dougtubes refer to certain tubes they carry being similar to this or that one, but I’ve never actually heard of these out of that context. Any information anyone can give?

By the way… what’s the deal with SED? Dougstubes describes their 6L6GC as “The legendary 6L6 formerly known as Svetlana. Why are they so “legendary”? I see Svetlana tubes being retailed, so what's the connection between the SED and Svetlana?

And at last! Final question!

Sylvania's 6L6s are the "Holy Grails" of the 6L6s, just like Mullard EL34s are the "Holy Grails" of the EL34s.

What, then, if I may ask, is considered to be the “Holy Grail” of 12AX7/12AC7/12-WHATEVER the best ones for the preamp section are?

Once again, THANKS A LOT, guys!!!

 

[Russ]

I don't want to sound like a D!CK, but your posts seem a little long and have many questions. You might get better results making shorter inquiries. There isn't anything wrong with what you are doing but I am finding it difficult to try to answer these epic inquiry posts. Also, you need only post them in one area. If you split up the questions they will be best answered in the appropriate forum also.

 

[visualrocker69]

I don't want to sound like a D!CK, but your posts seem a little long and have many questions. You might get better results making shorter inquiries. There isn't anything wrong with what you are doing but I am finding it difficult to try to answer these epic inquiry posts. Also, you need only post them in one area. If you split up the questions they will be best answered in the appropriate forum also.

Sorry - just figured that if I had 10-15 questions, one post would be better than 5,6,7,8... etc

And my apologies for the double post too. It's just that the different areas get different people watching them, sometimes. Looks like you're an exception :wink:

Anyway, thanks for your replies, I find your advice most enlightening!

 

[recto-robbie]

I agree with Russ above but I will try to help just a bit,,, hell I got lost somewhere around the 4th question,,, I think?
Anyways you need to decide if your going to use other brand tubes or not. If something goes wrong because of them,, as far as I know the warranty is shot. But what mesa doesnt know wont hurt you either.
If you ever need to send your amp into mesa make sure you dont send it with different tubes.
This is just my opinion here, so after buying my first tube amp I became a bit fascinated with tubes. I bought numerous different power and preamp tubes. I would assume after buying a $2000 amp you can afford to buy some tubes. I highly suggest reading as much as you can getting ideas and such about tubes you think you may like. You must not take anybodies word for granted about tubes because everybody likes different sounds. I would make it a point to buy quality tubes but then again I personally would wait a bit before looking into NOS tubes. Nothing hits harder than having a $200 set of tubes sitting there collecting dust if you find the $50 set is more to your liking.
What I did after some research was purchase a few different highly suggested preamp tubes,, and swap them around to find what I liked the best. Whatever it was is sitting in my v1 spot right now. V1 is where you will hear the biggest difference in sound. Followed by power tubes in my opinion. Make sure also not to just buy 5 or 10 of the same preamp tube like I did because someone said they are great,,, I didnt like them, now they collect dust.
You are going to have to wait for someone else to help you with the questions soley pertaining to the Mark4 because although I pretty much understand the different available tube combonations, I dont own it so I will not suggest anything directly pertaining to it.
You can always just stick with mesa tubes but not only will you pay more, you will be limited to only their sound. They are not bad by any means but I easily found better. If you decide to go with different tubes I highly suggest Dougs tubes, I have ordered from him numerous times and have always been pleased. I also suggest Eurotubes, Ive ordered from them once or twice and was happy with eveything. The only prob I see with Eurotubes is they only carry JJ's. If you find you dont care for JJ's then Eurotubes becomes useless to you. I ordered once from the Tube Store and got good tubes but didnt care for their uninterested attitude. If you decide to go with dougs or eurotube I highly suggest calling them directly,, both of these places know their tubes and know what the hell they're talking about. You will quickly see that they both love to talk tubes and amps. They will take their time explaining things to you and will even give some suggestions if you want. But again, what they think sounds good,, you may not care for,,, its all up to you.
Oh yea, those mesa color codes are used for matching sets. I really dont know if there is any difference other than you would match two reds with two reds will equal a matched quad.
What dougs and eurotubes does is find tubes in whatever brand your interested in and match up the,, I think plate current?,, to mesa specs so they will work just fine in your amp. They both explained to me that they have messed around with enough mesa tubes to know exactly what they need to look for to match their tubes to mesa specs. Talk to them,, they will take the time to explain all this to you and when you hang up the phone you will be confident your going to get quality tubes that work fine in your mesa.
So anyways I cant possibly think of anything more right now and I hope you enjoyed reading all this like I did yours!!!!!
Good luck

 

[recto-robbie]

Man oh Man,, I just went back and looked over your novel of questions and you even have a f_ck_n grand finale.

 

[Russ]

Feel free to post up as many times as necessary to get your information. Loading a single thread like this is enough to get yourself even more confused because not everyone is going to be able to digest everything. Then you also might get things confused yourself because everything will be clumped together. Single ended topics for threads get to the point. No one really cares if you post up 10,000 questions provided they can easily weed through them to assist you. This particular thread is a little heavy to take in all at once. I tried to answer it the best I could in your duplicate in the other section. But at that, responses were somewhat condensed because of the amount of inquiry that was initiated by the thread. When there are that many questions in one thread it is almost like asking for a resume or for someone to fill out a survey or application. I know you understand what I am getting at here. There is no limit to the number of posts but to make things easier for people to respond and to give you a good quality reply without being distracted by the multiple fronts being addressed K.I.S.S.

 

[Jak0lantern01]

My vote is also for DOug's tubes. I'm not going to knock Eurotubes, but the JJ's just weren't for me, very abrasive to the ear. The combo I got for my single rec from Doug's has the amp singing.

 

[Russ]

Just use it as is with a stock complement until you determine what you want to change about the tube performance.

 

[recto-robbie]

yea listen to Russ, he's making some good sence here, and I must say after reading some of your previous posts, from what I gather, it sounds like you assume the Mark IV is the holiest grail of amps out there. If thats the case then you should get plenty of excellent sounds with stock tubes and the billion knobs you will be adjusting forever. Enjoy the amp and mesa tubes and learn all the functions it offers. I checked the amp out a week or so ago, and if your like me, and I would guess most people out there, it will be weeks before you even have a fraction of an idea whats going on with it. At least you will know what characteristics you would like to change with new tubes. DONT RUSH ANYTHING, YOU WILL HAVE TUBES YOU DONT CARE FOR BEFORE YOU KNOW IT.

And Jackolantern01, ive got the single rec also so im wondering what combo pack your using? Im always a fool to try something new being that it only takes 2 power tubes to change my setup.

 

[Jak0lantern01]

From Doug's, this is the pre-amp combo I'm currently using. Also, factor in that I'm currently using KT77's for my power amp. I may switch back to 6L6's, though at some point.

Here's one of the preamp tube combo's that seems to work out
> great in Mesa amps.
> V1 - Tung-Sol 12aX7
> V2 - Sovtek 12AX7LPS
> V3 - Penta Labs/Shuguang 12aX7C
> V4 - unlabeled Shuguang 12AX7C9
> V5 - balanced Sovtek 12AX7LPS

 

[recto-robbie]

Yea I decided to stick with Doug because of the variety he offers and he treats me like a friend would. He even emails me periodically to see how my tubes have been working.
I like to swap tubes around for fun and have you ever noticed that your sound becomes old news to your ears once in a while? Thats when I swap them around and presto,,, new amp.
Right now im using the TAD 6l6wgc's and think they are really nice. I think I like them better than my mesa 6l6's and jj 6l6's. They are a strange looking 6l6,, they are a short bottled version. Different.
Ive got a set of those jjkt77's from doug also,, happy with them, great replacement for an el34.
Right now ive settled on a preamp tube selection of.
V1 = Penta Labs 12ax7
V2-V3 = Tung-sol 12ax7ri
V4 = JJecc83s
V5 = Balanced Tung-Sol 12ax7
Have you tried the Penta Lab12ax7 in v1 ? I think im liking the sound of that over the Tung-sols in v1.
Are using the head version? Im using the ROV combo and have wanted to try those Sovtek12ax7lps but doug and bob say that they dont suggest long plate tubes in combos. Ive only once tried one, it was a GT12AX7-M
and it became microphonic on me in a month.

 

[Jak0lantern01]

I'm running the combo, also. I went from Mesa pre's, to the JJ's, now I'm using the Doug combo, which I'm happy with. The only reason I may be going back to 6L6's is that I just used a vintage 2x12 Mesa cab at a gig this weekend for the first time and I was having issues with my tone, a bit too thin. I think with being a one guitarist setup, I needed a bit more boom to my sound. I may have just needed to adjust my settings on the amp, but we were flying by the seat of our pants with this gig. Let's just ask the question, "Was there time for a real soundcheck.....?"

 

[recto-robbie]

I understand that, I think the 6l6's will help a lot with the bottom end because I find all the el34's and the kt77's to be very mid range orientated.
I will tell you though, the addition of my 2x12 recto cab was one of the best things I added to to my setup to achieve the sounds I wanted. Its a great add on for all sounds but if you want that deep brutal chugga, chugga sound,, you cant beat adding the cab. It also makes everything sound so much fuller and 3 dimensional.

 

[recto-robbie]

Im sorry I forgot to ask the question I wanted to,, seeing that you use a combo, have you ever had any issues using long plate preamp tubes?
Have you noticed any going bad on you quicker than you expected?

 

[Jak0lantern01]

My 2x12 is running an EV and Celestion combo. I might swap one of those Black Label EV's in when I have $$$ to toss around. I've also never tried long plate pre-amps since they're not recommended for combos.

 

[recto-robbie]

I thought the Sovtek 12ax7LPS are long plates. LPS ?

 

[Jak0lantern01]

Goog point, I never really looked at what I was using. LOL. Anyway, I've had that setup for over a month and a half, maybe longer, and played that gig last weekend, no issues.

 

[HipKitty]

Let me put my 2 cents in....but only regarding the output tubes. The preamp tubes seem to be covered pretty well by earlier posts....

Not only do I have a Mark IV for my shop, but I have serviced quite a few of them over the last 10 years.....

You've got to remember that tone and response from an amp is very subjective to your own tastes.

With that being said, the Mark IV can use the following output tube combinations:

(all) 4 6L6 tubes
(all) 4 5881 tubes
2 EL34 tubes (both outside positions) with 2 6L6 tubes (both inside positions)
2 EL34 tubes (both outside positions) with 2 5881 tubes (inside positions)
(all) 4 6V6 tubes (**warning** amp MUST be run in Tweed and Simu-class)

As you can see, the Mark IV is very flexible, that is why it is one of my shop amps. Due to it's (very) high gain , it is always used to test preamp tubes for noise, microphonics, etc...regardless if they are Groove Tubes, Ruby, TAD or otherwise.

You can easily download the owners manual from Boogie's website.

Regarding output tube manufactures and companies that test and brand their spec tubes...here's a short list of what most of my customers request for their Mark IV's (as well as other amps):

Winged C (aka SED)
Mullard
Tung Sol
JJ
Groove Tubes Brand
TAD (Tube Amp Doctor) Brand
Ruby Tubes Brand

I rarely get requests for the Sovtek or Electro Harmonix (EH) brand tubes. There was a time when Sovtek was THE ONE, but inconsistancies in their manufacturing has dropped them off the radar for most of my clients.

Hope this helps some...I strongly suggest that when you buy the output tubes, have them pre-tested and matched. Also keep in mind that ALL tubes, even the pre-tested/matched tubes can experience what is called infant mortality...early death...not as a result from your amp, just a materials defect in the tube.

Of course, I STRONGLY recommend a rebias when changing ANY output tubes. I use the analogy of the ouput tubes biasing as setting the gaps in your spark plugs of your car. Sure, you can just stick them in and go, but if you want peak performance, set the gaps appropriately and you'll have better gas milage and better performance.

 

[jetdriver]

All good posts here. A sage advice.

I think recto-robbie hit the nail on the head. Wait for a while and get to know your (very versatile) amp before changing tubes. Otherwise, how will you know if the tones you like/dislike are coming from the amp circuitry or the tubes?

 

[phaboo]

I tried to read all your questions but then my head exploded. My walls are a mess.