EL34 AND 5881 Valve Visible Differences?

[Speiro]

Hi, can anyone tell me the visible difference between an EL34 and a 5881 valve? I have a JCM 900 head from the early 90's and I've been told the 900's have been made with both. The valves in the amp have no markings on them. Can you help?
Thanks
Tony

[charvelguy]

Re: EL34 AND 5881 Valve Visible Differences?

5881's are noticeably shorter. Construction too, the 5881 is more like a 6L6.. the El34 will have a much different getter and the plates are typically longer.

Best thing to do is google search images and see if you can make the comparison to the ones you have but the height is a dead giveaway.

[toejam]

Re: EL34 AND 5881 Valve Visible Differences?

A 5881/6L6 I believe is a little shorter and fatter bottle than an EL34.

[charvelguy]

Re: EL34 AND 5881 Valve Visible Differences?

yeah, the diameter of the glass is not as noticeable I think so I didn't mention it. They are stouter overall.