sub 6L6 for EL34?

[iknowjohnny]

Ok on the 1k's. What about a more correct OT? I don't wanna rush things but i really think i am going to convert. I popped the el34's back in and then the 6l6's again and theres no doubt...the 6l6's IN THIS AMP have a thicker richer midrange which is what i have been trying to get out of the 34's from day one with this build. Odd because i never liked 6l6's much before. Maybe it's because in this amp that was built around 34's they don't display the normal 6l6 sound. I must admit they sound like a el34 in this amp except for the thick mids i mentioned. Could this be due to the OT primary being lower than is usually implemented in 6l6 amps? Maybe i SHOULDN'T consider a 6l6 correct OT ! (head scrathing smilie here...dammit AG, get some good smilies !:)) Actually i guess not or turning to 4 ohms would change the tone to typical 6l6 which of course it doesn't. So i wonder why.....proabbly the entire circuit contributes. But that would suggest 6l6's and el34s actually do sound much more alike than is typically said.

[Alexo]

It really depends on the screen voltage, but for the most part, I'd prefer to run 6L6's closer to a 4K load than 7 or 8 K. If the screens are really low, like 50V+ lower than plate voltage, maybe you could run them at 2X the impedance, but you're probably fine just dropping them in there, biasing it up and letting'er rip.

[M Fowler]

I do that a lot, build an amp that I fully intend to run EL34's and end up using 6L6.

But I prefer 6L6 or 5881 tubes and always have, but a Marshall amp with EL34's is sweet too.

Mark

[Gaz]

You know, I've been using JJ 6L6s in a Plexish amp with that same Magenetic Componets OPT, and I prefer the tone as well. No need to change the impedance, which you've already figured out. 1+ on keeping the 1ks. FWIW, I prefer the 6L6s to KT77s as well.

[Ian444]

So i wonder why.....proabbly the entire circuit contributes. But that would suggest 6l6's and el34s actually do sound much more alike than is typically said.

I could agree with that. Its strange, the more I actually experiment, the more I find that what works for others may or may not work for me. Seems that theory is good for making sure an amp is stable and that the tubes will live a long life, but for what sounds good, there is no theory

[iknowjohnny]

Guess i'm not alone. This makes me feel a bit more like i AM on the right track. But the thick warm mids are a big wake up slap in the face even if none of you felt the same. Thats probably the #1 thing i have always looked for in an amps tone, and there it is, better than any el34 i've used yet w/o losing any of that sweet rich and smooth top. Thats what i usually hear with 6l6....a harder more strident top end and mids that always sends me running back to el34's. But in this amp they seem to be spot on.

And from what you all are saying, no need to touch anything, eh? grid stoppers? (5.6k now) anything? How about the JJ's? Are they considered good and if not what is? I'm not familiar with 6l6 at all and don't know who get the buzz.

[M Fowler]

I like the JJ 6L6 and Tungsol STR 6L6.

[Firestorm]

Mark --

Is that the New Sensor Tung Sol? How would you say it compares to the SED (Winged C) 6L6 from St. Petersberg?

[M Fowler]

I have never used the SED (Winged C) 6L6 from St. Petersberg, so I based my flavor on new GT, current JJ's and the new Tungsol.

I have some older 6L6's and 5881 but nothing great to compare with.
I sold out my old stock in 2003 for some stupid reason, I moved.

[iknowjohnny]

So i take it the JJ is as good as anything and the difference at that point is just cork sniffing ? Guess i'll stick with them then. I wondered because aside from JJ EL84's i never liked any of their tubes, and the EL84's i only liked because there wasn't anything else as far as current production that was even decent for years. Their EL34's and 12AX7's especially sounded dull and lifeless.

EDIT: heres what i was going to ask and forgot....looking at a number of fenders, i noticed they either have no grid stoppers at all or 1.5k's on the 6l6's. Think i should remove the 5.6k's and either put 1.5's in there or none at all ?

[Firestorm]

Most later Fender amps have them. They seem to show up first in the 5E8. You could try backing off gradually. Try a 3K3. If that's OK, you could try 1K5. I doubt you can get away with none unless the whole build is perfect. A lot of older Fenders actually should have had them, but nobody knew because the amps weren't being cranked up yet.

[Gaz]

No need to change the grid stoppers, unless you want to experiment. The goal isn't to reduce the stoppers until the amp oscillates - they are there to prevent blocking distortion and perhaps tame some fizz. This all depends on the circuitry preceding the power tubes, of course.

[rdjones]

Guess i'm not alone. This makes me feel a bit more like i AM on the right track. But the thick warm mids are a big wake up slap in the face even if none of you felt the same. Thats probably the #1 thing i have always looked for in an amps tone, and there it is, better than any el34 i've used yet w/o losing any of that sweet rich and smooth top. Thats what i usually hear with 6l6....a harder more strident top end and mids that always sends me running back to el34's. But in this amp they seem to be spot on.

And from what you all are saying, no need to touch anything, eh? grid stoppers? (5.6k now) anything? How about the JJ's? Are they considered good and if not what is? I'm not familiar with 6l6 at all and don't know who get the buzz.

I wouldn't mess with those 2 values (stoppers and screens) as I suspect they are a major part of what you are hearing.

rd

[212Mavguy]

to the OP...

Sub 6l6 for el34 because you like the tone better? Why not? Sounds like you know how to fix something that breaks in you amp. If that is the case...then if nothing breaks, no need to fix it, especially if the tone is what you like. Set the bias to what works for decent tube life and your ears and play the snot out if it with a big grin...and if something breaks, fix it then. Lots of guitar amps can run either tube type. Time will tell in your case.

Peace.

[iknowjohnny]

Well guys, i've heard all i need. Look like it's good to go as is, so i'll leave it as such. I'm digging it as is anyways. Thats thick mid is just so so sweet. I always based which amps are best on that one detail m ore than anything and while i'm surprised i get that from 6l6's, i'm just ecstatic about it. I 've been playing teles for the last few moths and haven't touched my beloved strat. I was thinking i'd become a tele man after all these years. But i played it with the 6l6's last nite and holy %$@#, the things sounded so frigging fat and rich i was blown away. With such an improvment i probably won't pull the chassis and start experimenting again................





.............for at least a month ! LOL!

And thanks for all the replies.