Talk to me about tubes

[Aden]

I've got myself a carvin mts 3200 head that i'm pretty happy with, or happy enough for my budget right now, but I'm looking to make it dirtier and darker. Right now it has groove 6l6s in it that aren't that old and sound great clean, lots of headroom and chimy clear defined sound that works well with my guitar.. So i want to preserve that clean sound if I can as much as possible. The pre-amp tubes I haven't really looked at, but they are groove 12ax7s I think.

I know a little about the differance between power tubes but have no expierience swapping them, and know nothing about pre-amp tubes or positions of pretubes and the like. Also the amp has a biasing switch on the back to switch between 6l6 type tubes and el34 tybe tubes, if i were to switch to something else, or switch the pre-amp tubes should I have it professionally re-biassed?

Like I said, I want to get a more dirty, dark sound out of the amp with some growl and bite. The carvin has tons of gain most of which I don't use, I generally have the gain between 5 and 6 at the highest and roll it down when I need to.

Can I get some advice? thanks

 

[Baltar]

Re: Talk to me about tubes

what you want sounds partially conflictive to me.
did you try out effects before?

try out a hughes&kettner warp factor pedal. it's a very dark sounding distortion pedal.
it can make your sheep bite like an engl-amp (well, depends on the sound you want ).
a good musicstore will let you try one out for sure

 

[Scott_F]

Re: Talk to me about tubes

Swapping power tubes can get expensive. But, I'd try putting a pair of 5881 new production Tung Sols in there. That will lower the gain slightly. Break up a bit sooner.

A word of caution though, a leopard can't change its spots. Many folks end up with a firebreathing amp with tons of clean headroom and then they spend months chasing their tails trying to get it to break up sooner, lower the headroom, etc.. In the end , they spend way too much money and end up selling the beast in frustration.

If you decide to use EL34's, don't get the "L" version of the JJ's. I'd look at some of those Mullard reissues. It'll give you more mids, less chime and a bit less gain. I think I'd go with the 5881's first. Is there a bias adjustment pot on the bottom of the amp chassis somewhere? If you dont' know what you're doing, take it to a tech. Or, do some internet research and learn how to bias it.

 

[Aden]

Re: Talk to me about tubes

After reading around I've be come interested in 5751 pre-amp tubes, from what it says at "the tube store" they will cut down on the gain a bit and make the amp push the powertubes harder, possibly getting more break-up as I crank it up. Am I getting that right? Would that get me the meaner growl I'm looking for or would it do something else entirely?

 

[AdmiralB]

Re: Talk to me about tubes

That will lower the gain slightly.

Power tubes don't have gain.

 

[AdmiralB]

Re: Talk to me about tubes

they will cut down on the gain a bit and make the amp push the powertubes harder

They will reduce the amount of clipping that occurs in the preamp at a given volume level, i.e. the amp will be cleaner at any setting. It does NOT mean you will drive the power amp harder.

Depending upon the amp's design, doing so may shift the clip point away from the preamp towards the PI or power amp...or you may not. Power tube clipping is a fairly subtle thing anyway.