Difference between 6L6 and 6L6GC

[sgtbaker]

What is exactly the difference between these two? And if an amp says you can run 6L6GC's through it can you just run regular 6L6's? Thanks.

 

[stoz]

There's a recent thread entitled 'sylvania 6l6GB', in which Timberwolf gives an explanation of this naming system, and I gave some duff gen. which you should skate over (Ho hum). Have a look - there's references to good websites too.

 

[212Mavguy]

You can run 6l6gc in an amp designed for 6l6, but it would definitely be risky to run 6l6 in an amp designed for 6l6gc. The 6l6 in that application might very well fry and die, and in the throes of dying might also cause some need for amp repairs. 6l6gc is rated for higher voltage and current for more wattage per tube pair in circuit than the 6l6.

 

[Timbre Wolf]

For decades, people have been discussing 6L6GC tubes while simply referring to them as 6L6. You can easily tell them apart: true 6L6 are metal jacketed tubes, and look quite distinct. Metal 6L6 can not be safely substituted for 6L6GC in modern amps, as 212Mavguy says.

If a modern amp is touted as using "6L6" tubes, you can immediately translate that to the more accurate 6L6GC.

- thom

 

[212Mavguy]

Right on, Thom. Key word in your post is "Modern" amps.

Some folks like to modify old organ and PA amps for guitar use. Lots of older amps use lower voltage main trannys allowing the older style 6l6's. You can lump 6l6 metal jacket, 6l6g, 6l6gb, stubby 6l6wgb, US military 5881, and 5932 in the "not for modern amps" category. Lots of great choices to pick from in those types if you have the not so common amp that can run them safely. I picked up a metal jacket 6l6 in a lot of power tubes won on ebay and ran it briefly in my modded Silverface Champ, it sang gorgeously when pushed. It's worth it to get or build a boutique amp designed to run those older tubes. Also hard for most others to nail your resultng tone... :lol:

 

[Timbre Wolf]

Right on, Thom. Key word in your post is "Modern" amps.

Some folks like to modify old organ and PA amps for guitar use. Lots of older amps use lower voltage main trannys allowing the older style 6l6's. You can lump 6l6 metal jacket, 6l6g, 6l6gb, stubby 6l6wgb, US military 5881, and 5932 in the "not for modern amps" category. Lots of great choices to pick from in those types if you have the not so common amp that can run them safely. I picked up a metal jacket 6l6 in a lot of power tubes won on ebay and ran it briefly in my modded Silverface Champ, it sang gorgeously when pushed. It's worth it to get or build a boutique amp designed to run those older tubes. Also hard for most others to nail your resultng tone... :lol:

Excellent!!

By the way, your list is missing 6L6GA and 6L6GAY. Yes, I admit that some of my tubes are GAY. Nice tubes, those!!

- Thom

 

[212Mavguy]

Right you are again, Thom!

6l6ga and 6l6gay series are some seriously wonderful sounding tubes. 6l6ga is similar to 6l6g cokebottle but the guts are mounted in a smaller bottle then their 6l6g series daddies. 6l6gay were 6l6ga built for military use. Sorry to say I don't have any gay tubes, waaaaaaaaaaaah! but have a couple pairs of Sylvania 6l6ga that sound splendid in my Siegmund amp head. Not a good design for combo amps, best to use 'em in a head.

Again, these are in the category of not able to handle voltages and currents found in 6l6gc rated modern guitar amps.