6CA7's

wdelaney72 · Post by **wdelaney72** » Wed Jun 11, 2008 12:24 pm

I can't compare to the original 6CA7, but a set of Shuguang 11th Gen EL34 from TubeTramp are your best bet. You can ask for a set with higher headroom, which I believe 6CA7 are supposed to be like an EL34 with more headroom. I'm sure it's not exactly the same thing, but it will do the job. The 11th gen Shugs are the most durable modern production tube out there and Terry is the best for matching them and burning the drift out of them.

45auto · Post by **45auto** » Wed Jun 11, 2008 12:28 pm

thanks wd, i have a set of those. i thought they sounded really good (considering my limited experience with many different tubes) & really cheap too. i was thinking about trying a more aggressive bias & these might be perfect for the job.

Tone Slinger · Post by **Tone Slinger** » Wed Jun 11, 2008 12:58 pm

I dont really think there is a sudstitute. The 6ca7 is basically a 6l6 high beam design, except, that it is built to be operated at a slightly higher voltage than a standard 6l6. Thus, the el-34 comparisons. They (6ca7 and el-34) are ran at the same voltage in the circuit, which is higher than a 6l6, so either is a direct replacement for the other, operaing wise, but not tonewise. To me, the EH 6ca7 reissue sounds alot like a 6l6 EXCEPT, it has a bit more brown dynamic, than the 6l6. I am not for sure why this is, cause a 6ca7 is almost identical in design to a 6l6. I dont have the associations togather as to what the different operating voltages would do to the sound. I think the EH 6ca7's are way better clean than e-34's, and also sound a bit broader distorted than an el-34. They arent quite as warm and furry as an el-34, but have a tighter and quicker response with more top and bottom. They are warmer than a 6l6 though. So the best of both worlds concerning el-34 and 6l6. More headroom than either though.

cary chilton · Post by **cary chilton** » Wed Jun 11, 2008 3:14 pm

wow with the very active EVH forum, I would have bet they were many ppl with or have tried real 6ca7's and good give a comparison. I guess they are just too damn expensive for most to even consider trying -and that is understandable!

TubeGetter · Post by **TubeGetter** » Wed Jun 11, 2008 3:28 pm

The Shuguang's are good tubes by new production standards, but they have a unique tone for an EL34.....they sound very much like EL37's. They made my Marshall SL sound much more Fender and not as much Marshall. That's OK if that's a tone you like.

The 6CA7's have a unique tone that no other EL34 comes close to. Regarding the clones, technical operating specs have absolutely no measure of the quality tone a tube has. The construction techniques, materials, etc. of the orginal USA 6CA7's are what make them sound and last as long as they do. The reissues are not real clones, despite what any tube advertisement hype says. They make them look similar so it is more convincing to the layman, but they're not. Try doing an A/B comparison with an original and a reissue. You'll be surprised at the difference.

But if some people are happy with the reissues, that's great. There's no use stepping up a notch in tone, & paying more for it, if you're satisfied with what you have.

harddriver · Post by **harddriver** » Wed Jun 11, 2008 5:18 pm

45auto wrote:is there a decent modern substitute for the 6ca7? kt88? 6550? something that can handle the abuse perhaps. i had 6550's in my 67 plexi for all the years i had it & they did hold up well. alot of people seem to dislike their tone. i never really got the chance to compare then. when a tube died, i dropped in a new one. typically ge/rca/sylvania for $10 a pop from the local General Dynamics surplus.

I do like 6550's. The Sylvania 6ca7 was basically a 6L6 with an El-34 pinout. It was Sylvania and GE attempt at making a heavy duty EL-34 and they succeeded. They have alot more 6L6 characteritics than EL-34 IMO. 6550, 6l6, original 6ca7 Ge/sylvanias were/are beam forming element tubes similar to a Kinkless Tetrode(KT).

The closest current production 6550 you're going to get is the SED 6550C and the newer Shuguang/Valve Arts GE6550 clone tube. I hear these are very close to the original GE. They do look nice, I'm going to pick up a set soon for my 2203.

The EH6ca7's aren't perfect but they might be all were going to get for a new construction 6ca7. I think Shuguang builds for GT and they have a GE6ca7 clone as well but Groove Tubes owns the patents and rights to it, I hear they are still testing the latest batch but obviously there not working all that great or they would have released them by now.

jcs · Post by **jcs** » Wed Jun 11, 2008 10:32 pm

try mixing a big bottle 6ca7 with a true european el34 for a different tone.

i mix 6l6 tubes all the time, one of my fave mix is an rca blackplate 6l6gc and a ge 6l6gc in my 70 super reverb.

eric johnson has been known to mix different el34s.

Tone Slinger · Post by **Tone Slinger** » Sat Jun 14, 2008 10:32 pm

Cool idea !

Roe · Post by **Roe** » Sun Jun 15, 2008 11:12 am

I just took the Sylvania 6ca7s out of my express - a pair of rtf el34s sound much better to me in this amp. I'll try the 6ca7s in one of my other amps

jcs · Post by **jcs** » Sun Jun 15, 2008 1:46 pm

hows the bottom end sound with the rft's?

sometimes they can get mushy in the bass,but overall rft's have some of the most refined sounding distortion imo.

Roe · Post by **Roe** » Sun Jun 15, 2008 2:28 pm

this pair aint mushy in the bass. however, the express does not have the clearest and tightest bass

Tone Slinger · Post by **Tone Slinger** » Mon Jun 16, 2008 7:08 am

Yeah, I had a pair of Svetlana El-34's in my 800 5 or 6 yrs ago. They sounded just like early Schenker, like on that "Live at the Roudhouse" gig from april '76 (UFO). When cranked up, they creamed out real well. Super warm mids, but not alot oh high end and the bass was a bit mushy/furry. Still, sounded like old Mullards, as far as other El-34's go.

Rickfox · Post by **Rickfox** » Wed Jul 02, 2008 11:57 pm

Hey Eddy!! Stay on track for the Sylvania 6CA7's!! I used them for years. I used to get them from Mesa for my Marshall. Mesa called them STR-416. In the early 90's (it could have been later), I called Mesa and they told me they went out of production in the mid-80's and were no longer available through them.
The guy even commented that if he could get them, he'd keep them for himself! A load of crap??? All I can say is, I've tried GE (not the same),
Siemens, Mullard... nothing touched the balls, warmth, and clarity of the Sylvanias.
They totally changed the dynamics of my Marshall. People have paid hundreds for a single German 12AX7, is the joy of playing worth the $$$$?
Absolutely!!
Rick

Rickfox · Post by **Rickfox** » Wed Jul 02, 2008 11:59 pm

Hey Eddy!! Stay on track for the Sylvania 6CA7's!! I used them for years. I used to get them from Mesa for my Marshall. Mesa called them STR-416. In the early 90's (it could have been later), I called Mesa and they told me they went out of production in the mid-80's and were no longer available through them.
The guy even commented that if he could get them, he'd keep them for himself! A load of crap??? All I can say is, I've tried GE (not the same),
Siemens, Mullard... nothing touched the balls, warmth, and clarity of the Sylvanias.
They totally changed the dynamics of my Marshall. People have paid hundreds for a single German 12AX7, is the joy of playing worth the $$$$?
Absolutely!!
Rick

TubeGetter · Post by **TubeGetter** » Thu Jul 03, 2008 10:51 pm

Rickfox wrote:Hey Eddy!! Stay on track for the Sylvania 6CA7's!! I used them for years. I used to get them from Mesa for my Marshall. Mesa called them STR-416. In the early 90's (it could have been later), I called Mesa and they told me they went out of production in the mid-80's and were no longer available through them.
The guy even commented that if he could get them, he'd keep them for himself! A load of crap??? All I can say is, I've tried GE (not the same),
Siemens, Mullard... nothing touched the balls, warmth, and clarity of the Sylvanias.
They totally changed the dynamics of my Marshall. People have paid hundreds for a single German 12AX7, is the joy of playing worth the $$$$?
Absolutely!!
Rick

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