6v6 tube swap in markIV

[KYBOOGIEFIEND]

Hi, new to the board.Have played Boogies for years.Recently sold my ROC as I am now a bedroom player.Long story short I had my left wrist mangled pretty good and it took me a few years to even hold a guitar neck again. Well now I am playing again and I want to know if you can swap 6l6 for 6v6 in mark IV.If so how does it affect the sound.Anyway thanks for listening to an old fart that wants to try and rock again.

 

[ursinus]

I love the 6v6's. They make the amp more tonally rich in my ears. Also, you get much more of the power amps tone at much lower volumes. I love them, I will probably never go back to any other tubes in my MKIV. Just be sure you purchase them from Mesa or Doug's Tubes so you don't cook anything. You do have to run the amp in tweed mode for best results. 40 watts is still plenty loud...... 8)

 

[treelifeUK]

You have to only run the amp in "Tweed", "Simul-class" and plug the speaker jack-plug into the 4 ohms speaker socket!!!!!!!!!!!!

 

[stoz]

Its all there in the manual - I'm a new Mk IV user, and downloaded the manual from the mesa site. It's worth a look. Everything is covered in there.
Cheers,
Craig

 

[HipKitty]

The JJ brand 6V6 tubes currently seem to be the best in the field in regards to tone, response and durability. They can take high plate voltage found in the Fender Deluxe Reverb type amps and sound absolutely great! I get a cross section of clients that play country to alt-country to rock to Nu-metal and these tubes do fit each style, regardless of amp manufacturer.

I've been seeing some failures/faults crop up in the Electro Harmonix brand 6V6 over the last year, which is unfortunate as they started out as a great tube!

The chinese 6V6's by Groove Tubes, Ruby Tubes and TAD (Tube Amp Doctor) would be my next choice after the JJ's.

Just make sure that they are pre-tested and matched and have your amp rebiased for the new tubes.

 

[visualrocker69]

Just make sure that they are pre-tested and matched and have your amp rebiased for the new tubes.

Mesa amps are fixed bias, so that last bit isn't necessary.

 

[HipKitty]

actually visualrocker69, that last bit IS important....

yes, Boogies are fixed bias amps. However, that doesn't that mean you never bias them.

To have any tube amp operate to it's best, they must be properly biased, regardless of whether they are "fixed" bias or "adjustable" bias. In the case of a "fixed" bias tube amp, it usually means that the amp must be biased by a tech that knows what they are doing. Many of us "old dogs" like to refer to the spark plug/car analogy...you can buy the spark plugs off the shelf and put them in as is and your car will operate ok. However, if you want the best gas mileage and performance, you have the spark plug gap(s) set the the right gauge. Essentially, biasing new tubes to your amp is like fine tuning the engine of your car.

Back to the Boogies....every new Boogie is biased "cold" from the factory. Every Boogie owner that has had their Boogie rebiased to proper settings (by my service) has been blown away by the difference in tone and response. I'm sure that the same would be true for you if you would have your Boogie rebiased too...as long as it's done properly.

 

[Chad]

Buying tubes that are to Mesa spec are like buying spark plugs that are already gapped to the proper spec (to use your analogy).

Whether adding a bias pot or whatever other bias adjustment method is a good idea is open for debate (and another topic), but from what I understand if you buy tubes that are in the correct range you *never* need to rebias a Mesa amp.

 

[HipKitty]

Chad, even though Mesa's tubes fit within a certain range (or spec), that doesn't mean that the amp itself isn't biased for the best tone and response. Boogie still biases their amps "cold". They do so to insure longer than normal life expectancy from the output tubes. I'm sure that if you read through some of the posts on this forum, you will see what I'm trying to convey here. Every tech that's checked the biasing of any Boogie that's either new or has never had it's biasing changed will agree.

 

[ursinus]

Biasing a tube cold is not always a bad thing. 6V6's in tweed mode pull about 6-8 mA at idle. Super cold when you consider that a 6V6 typically pulls 26-28 mA. Anyway, in the MKIV it sounds awesome.

 

[Chad]

Chad, even though Mesa's tubes fit within a certain range (or spec), that doesn't mean that the amp itself isn't biased for the best tone and response. Boogie still biases their amps "cold". They do so to insure longer than normal life expectancy from the output tubes. I'm sure that if you read through some of the posts on this forum, you will see what I'm trying to convey here. Every tech that's checked the biasing of any Boogie that's either new or has never had it's biasing changed will agree.

I totally get what you are saying, but from a technical standpoint, you *never* have to rebias if you buy tubes to Mesa spec. From a *tonal* standpoint, it might be a good idea, but that's subjective as ursinus just pointed out. Also, will your rebiasing method void a warranty?

 

[HipKitty]

you know, ursinus is correct regarding the cold biasing not being a bad sound to some. you, of course are correct in the fact that you can buy Mesa's tubes and drop them in without a rebias. I think we can all agree that tone and repsonse from an amp is very subjective. Some folk like their coffee hot, some like it warm and some like it iced...lol!

Regarding the Boogie warranty..Boogie suggests that you have your amp serviced by an authorthorized repair center. We see a cross section of amps that are under warranty and those that are out of warranty. Many of our clients that have Boogies under warranty will forgoe the warranty in order to have their amps biased to the tubes.