What do you know about the 6CA7 power tube? If you’re like me, you know that Edward Van Halen favored them back in the day, and that they are similar to EL34s but different.
You might also know that they never came stock in Marshall heads, that EVH favored Sylvania big bottle 6CA7s, and that good, new 6CA7s don’t exist (or didn’t).
That last part is one reason I was super curious about Eurotubes’ recent announcement that one of three new JJ Electronic tubes is a big bottle 6CA7. The other reason I wanted to know more is because I’m one of many folks, including many touring musicians, who really dig JJs. So I hopped on the phone with Bob Pletka at Eurotubes to find some missing pieces of the 6CA7 tube puzzle.
Before getting into why JJ came out with this tube, here’s more from Bob on the tube itself and maybe why EVH liked it:
> “The 6CA7 is really about as close as you can get to melding a 6L6 [clean “Fender tube”] and EL34 [dirty “Marshall tube”]. It has a fat, round low-end to it – the KT77 also has it, but has a different harmonic sound – and has a sizzly high end. So the 6CA7 is slightly more subdued on the top end, as all EL34s are.”
> “A regular EL34 is a little mushy – the dynamic response is a little slow, so they have the reputation of being a ‘slush bottle.’ Some people really like that, and cranked and really working hard they have that ‘breathiness.’ But jump into that more modern world – Eddie and Malmsteen stuff, players who really demand a tighter dynamic response and more articulation – [and that’s where the 6CA7 shines].”
> “That’s one of the reasons Malmsteen chose the E34L [in his new amp, maybe?] – it’s basically the tightest EL34 made. There’s more articulation there. That’s one reason we stay with that in people looking for that Eddie sound.”
> “6L6s in general are quicker in their dynamic response. That’s in the big bottle 6CA7, but [the 6CA7] has a higher upper midrange [key for EVH] and top end more akin to an EL34. It has a nice harmonic structure, so it’s a unique sound.”
And the million-dollar question: Do they sound like the old big-bottle Sylvanias?
Bob said: “Yeah they do. They’re really close. Biased up at the same current in the same amp, the JJ is a little warmer. I think the Sylvania is slightly harder.
“If you put 20 guys in a room and say, ‘Hey, audition these things along old-stock big bottles,’ I think it’ll be pretty split. Some guys like a little harder sound, some guys like a little bit extra warmth.”
I want to try them. Bad!
Here’s Bob’s answer to my question about whether the JJ 6CA7 was developed because of Edward Van Halen tone-related demand:
“On my side [he works closely with JJ] it was part of the thinking because I know people are looking for that little thicker sound – but you can’t cop a great EVH tone at a puny volume. That’s something that’s achieved by cranking your amp.
“But in communicating with the guys who own JJ Electronic, they don’t have the background in being around or growing up around those specific types of [guitar] styles. Their background is very technical. So I didn’t say, ‘We need this because of great EVH tone.’ I said it would be a wonderful tube to round out their EL34 family, and good for us because it’s a tube to get a fairly specific type of sound in some cases.”
Very few 6CA7 clips on YouTube. Here are two where you can compare an amp with GE NOS 6CA7s and with EL34s. Unfortunately, the amount of distortion and/or how it was recorded and the riffs chosen make it tough to hear huge differences. But I THINK I hear some of that EVH midrange “clank,” if you know what I mean, with the 6CA7s vs. the slightly warmer tone of the EL34s. Maybe I’m just imagining it….
And last but by no means least, some ’78 Van Halen!