EL34 vs. 6L6

[Bloodsong]

depending on who you talk to, it seems that alot of ppl feel that an EL34 tube is not as reliable or ruggedly made as a 6L6. considering stalwarts like Marshall and Fender pretty much use only EL34s, is it just b.s. or is there some merit to this? i've owned amps with both and never really had any problems with either. i know alot has to do with how hot the amp biased but why is an EL34 inferior in quality of build? is it the smaller headroom?

[orangekick]

I've actually had more issues with 6L6's than EL34's. I've had a few 6L6's just explode for no reason.

[bassist_25]

I know I've read a forum thread somewhere about this same subject, but I can't remember if it was here or at Talkbass.

[lonewolf]

depending on who you talk to, it seems that alot of ppl feel that an EL34 tube is not as reliable or ruggedly made as a 6L6. considering stalwarts like Marshall and Fender pretty much use only EL34s,

Fender (and later, Mesa) used and still predominately use 6L6 tubes in their product line. It wasn't until they wanted to produce a "British sound" that they started using EL34s on certain models.

6L6 vs. EL34 = American sound vs. British sound and originally started with Fender vs. Marshall.

The 6L6 tube is physically larger and depending on the manufacturer spec, has 5 to 10 watts more power handling than the EL34--by definition, it is more rugged and can supply more headroom. This means that for any given amp design, the 6L6 can handle more power & heat than if designed for an EL34. Also, amps designed with EL34s are typically driven to the tube's maximum limits, resulting in quicker failure than if designed well within the tube's specs.

Quality is dependent on the manufacturer. The 6L6 is not "better" than the EL34, it is "bigger".

[Bloodsong]

that's kinda what i thought. i find myself liking the the sound of the EL34s these days cuz of the more biting midrange and throatier sound, but i don't want to start having tube snafus all the time. i bought SED "Winged C" EL34s for my Diezel cuz i read that they are the most durable tube you can buy, so we'll see...

[orangekick]

Just for clarification, 6L6's have a higher clean power rating where as EL34's have a higher distorted output rating. Most amps that run 4 6L6's actually put out right around 85-90 watts of power where as most EL34's equipped heads put out anywhere from 100-140 watts of power, depending on bias setting and the capabilities of the output transformer.

[lonewolf]

Just for clarification, 6L6's have a higher clean power rating where as EL34's have a higher distorted output rating.

I never saw these specifications listed on tube data sheets. Is there a web site that lists them or has pdf specs on them?

I was referring to the plate dissipation which is Wa(max).

The Wa(max) for an EL34 is 25W, although I think JJ makes a 30W
The Wa(max) for a 6L6 is 30W, although I'v seen them as high as 35W

Most amps over 100W use 6550 tubes, with a Wa(max) over 35W.

[orangekick]

You know, I had a page bookmarked with all that stuff and now I can't find it. I'll try to find that info and post it here.

[Hannibal]

Ages ago, I was using a 5881 as a direct replacement for the 6L6. It held up well, had a slightly higher plate dissipation, and seemed to last longer in my [long gone] Fender Bassman amp.

[JackANSI]

EL34's tend to have a higher heater current and higher max anode voltage than 6L6's...

I would not assume any amp is going to take them as a direct replacement for each other unless it is specified on the amp as being able to use both.

I hate to say it, as much as I love tubes, there are a lot of what I like to call "magic" involved in them. Sometimes one brand/batch you get sound great, the next it doesn't (and no amount of giggering gets it back). Even if you know all the great tricks and know how to bias your amp properly.

I'd bet that maybe 1 of 75 guitarist could tell the difference in a blind test between two sets of brand new properly installed tubes.

Unless you've hand rewired your amp point-to-point, swap components with tighter tolerances in, and danced in a circle while patting your head and rubbing your stomach, the whole tube thing is pretty much hit or miss.

YMMV as always.

[Bloodsong]

i have a Diezel with external bias points, so biasing is not too tough. i emailed the guy that builds them and was told to bias the pair of each tubes btween 60 and 65 mA. i know the bias is set on a Mesa and some ppl bitch its set too low and makes the amps sound sterile, but the tubes last alot longer. (i always thought my Dual sounded just fine.) you can actually put any type of tube in a Diezel cuz the range is set so wide, but the low end of 6550s and kt88s seem like overkill for a guitar to me.