6L6 vs. Sovtek 5881

[cellardweller]

Which tubes would you prefer?

And---------------------

What's the difference between a "premium" 12AX7A and a "standard" 12AX7A???

This is what the tech from ampeg said came in my amp stock;
Three standard 12AX7A's, and on premium 12AX7A.

 

[cellardweller]

C'mon, I really need some input on this "premium" 12AX7A thing...

What the hell is "Premium", as compared to what?

Why wouldn't all four be "Premium", and if there is not a reason for not using four of these then what is a good "premium" 12AX7A to use?

Please and Thank You for information.

 

[cellardweller]

I'm hoping on ordering these tonight...

Maybe I'll have to call Ampeg again...

 

[Major Tom]

The preamp tubes made today are said to vary a lot in characteristics of gain, etc. I believe that when a tube company calls 'em premium or something similiar, that means they have been tested and have met some minimum requirements or standards - you should in theory end up with a more predictable tube, although at a higher cost. The Sovtek 5881 is the equivalent of a 6L6GC, I think originally the 5881 designation was for a 6L6 tube version that met military specs, and was maybe a slightly lower power output but since the military doesn't use vacuum tubes any more, I don't think it means anything. I have those in my Hot Rod Deville, I have compared 'em to some other tubes, mostly used old tubes like GE and RCA's, and I think they work fine. Some reviewers don't like them, but others will say that they preferred them over something else they tried... All kinds of information and mis-information on the net about tubes if you want to read up on 'em.

 

[cellardweller]

I called Ampeg again, the tech there said that Premium, even though it was they who used it, is a misnomer, that ten year ago, there were alot of tubes on the market that fell into the standard category because they were inferior, but that this was not an issue any more unless youbuy an offbrand. He named a couple of offbrands, red-something, and another I don't remember...

I ended up going with the Sovtek 12AX7LPS, and the Sovtek 5881WXT perfect quad from The Tube Store.

 

[kevinmatthew1]

Helpful Tube observations

I've replaced my power tubes and preamp tubes a couple of times now. I noticed that you ended up buying Sovtek power tubes and preamp tubes, too. When I bought a matched duo of 5881s, Sovtek had a color coded rating on the box. I think they have sets labeled red, green, or blue. Red was labeled dirtiest, and blue was supposed to be cleaner. I don't know if this is still the case for Sovtek, but it might help you out with your shopping. Also, I think the "premium" rating on your preamp tubes might denote better signal-to-noise ratio characteristics. Most of the magazine articles and books I've read about preamp tubes seem to agree about that. You might find some of the "standard" preamp tubes that sound better for your particular amp, or it might depend on what style of music you play. Some people have to search everywhere to find really nasty or beautifully clean preamp tubes, and other people just buy whatever is around. I love tube amps! I've got a Sovtek Mig 50(two 5881s) that I run through a 2x12, and a Crate VC2110R(two EL84s) 1x10 combo. MMM...tubes... Any tubes are better than no tubes at all...