ELECTRO-HARMONIX 6CA7EH tubes in the 1959 '69 circuit

BBN-Boys · Post by **BBN-Boys** » Mon Oct 31, 2005 3:09 pm

As I understand, the 6CA7EH tube is an American version of the EL34. I've read that the sound of the 6CA7EH is cross between EL34 and a 6L6. I guess that means more lows and highs.. kinda mid-scooped...??

I was just wondering if any of you have used a quad of the ELECTRO-HARMONIX 6CA7EH (big bottle) in the 1959 '69 circuit. The B+ at the screens in my amps are running around 475v-490v. Can the EH 6CA7EH handle this voltage safely and still have longevity?

Since my amps have individual bias adjusters, I was also thinking of mixing EH 6CA7EH and JJ EL34L in the same amp. Please share any experiences you have with EH 6CA7EH tubes.

Thanks.

Billy Batz · Post by **Billy Batz** » Mon Oct 31, 2005 3:17 pm

I have the GT 6CA7s. Definitely not mid scooped. More headroom. Less high mid trashyness so less of the midrange bump. Does have a stronger low end and touch more glassy highs. As a whole Id say its more even in responce then current EL34s.

BBN-Boys · Post by **BBN-Boys** » Mon Oct 31, 2005 4:29 pm

I've read that the GT 6CA7s have been out of production for a while since GT is focusing on the new EL34M production. As a result, the GT 6CA7s are diffult to find and VERY pricey IMO. I guess I would also want to know how the EH 6CA7 would measure up in sound and quality agaist the GT version.

Billy Batz · Post by **Billy Batz** » Mon Oct 31, 2005 5:57 pm

Thts my point (thgouh I didnt really make it). Though Ive nevre compared them personaly Ive heard they are pretty similar. But I think just the fact that they are 6CA7s make the broad tonal similaritys. People use the same descriptions Ive found for the sylvanias too.

bluefuzzguitar · Post by **bluefuzzguitar** » Tue Nov 01, 2005 6:54 am

I have a quad of GE 6CA7's in my Super Bass. I'm also familiar with the GT6CA7 which is a copy of the GE. The difference between those two is what you generally hear about new-production vs. new or used old stock, i.e. the new-production GT's sound harsher than the original GE's (but only slightly so, it's still a great reproduction!), thereby making the GE's a tad smoother.

I agree with Dan. 6CA7's are not midscooped though the smoothness of their mids can be interpreted as such. So you get that mellow 6L6-like response and still retain the mids in all their glory. Plus, NO midhump! None of that upper-mid current-production EL34 crap. Instead you get delicious low end, smooth mids and glassy highs. This tube is more Fender-like than a regular EL34 or KT66.

Mike

BBN-Boys · Post by **BBN-Boys** » Wed Nov 02, 2005 3:45 am

Thanks for the input and clarification guys.

Anybody ever tried the ELECTRO-HARMONIX 6CA7EH??? Just wondering if there are any reliablity or consistancy issues with that tube. Any problems with handling 475V-500V at the screens?

Thanks again.

Zoso · Post by **Zoso** » Wed Nov 02, 2005 10:37 pm

I used them (the EH's) for a while when I first got my amp and never had any problem out of them. They are very sturdy tubes, at least all the ones I had. In fact, I'll probably be going back to them, I've been trying different EL34's, but the more I play, the more I think I like the sound I was getting from the 6CA7's.

BBN-Boys · Post by **BBN-Boys** » Thu Nov 03, 2005 3:01 pm

Thanks Zoso.
I'll try a set of EH soon.

Any recommendations for a good place to purchase those ELECTRO-HARMONIX 6CA7EH tubes???

Post by **VelvetGeorge** » Thu Nov 03, 2005 3:15 pm

newsensor.com

George

tonejones · Post by **tonejones** » Fri Nov 04, 2005 1:27 am

Had to share this,
A very nice looking Fawn 50W JCM 800 MV came in the shop for new tubes.

The duet of GT6550s he had ordered cost $150!!!

Post by **VelvetGeorge** » Fri Nov 04, 2005 12:46 pm

Ouch!

I don't think my SVT will ever get retubed....

George

Billy Batz · Post by **Billy Batz** » Fri Nov 04, 2005 6:03 pm

That is the only thing that kept me from getting an old SVT when Ive wanted one for soooooo long. You could go broke retubing them and you always run them hard.