Electro-Harmonix 6CA7EH Output Tubes!

Electro-Harmonix has released a Russian-made copy of the Philips/Sylvania "big-bottle" 6CA7 output tube! These are physical copies of the original Sylvania 6CA7 tubes that most pre-1980 Music Man amplifiers shipped with from the factory.
These look like the best bet for use in Music Man amplifiers... and should be able to withstand shock and high voltage better than most (if not all) EL34 types.
You can see them here:http://store.yahoo.com/thetubestore/ehx6 ca7.html
I have ordered a pair and will let you know how they work (although it might take awhile for me to get around to it).
Unlike the "Orion" 6CA7 "big-bottle" tubes, the 6CA7EH has the traditional envelope and base of the classic American-made Sylvania/Philips 6CA7.
Cool...

Any updates on these tubes? I have a 210 sixty-five that I want to retube and am considering either a pair of the Electro-Harmonix 6CA7-EH or the Electro-Harmonix EL34EH set. Which do you recommend? Thanks.

I've also a 210-65. I purchased a set of EH EL34's and didn't use them. The glass envelope lacked 'smoothness' (I looked really close and found 'glass orange peel', and they had some dimples that looked like trapped dust), leading me to feel that the glass' impurities, thermal cycling and shaking from movement might lead to premature failure. (Maybe I'm wrong? Maybe just that lot?)
I use Svetlana's via GrooveTubes (GTE34LS).
I'm pleased with them. Nice envelope. Adequate sound and service.
They do get a little 'rattely' after about a year, but the 210-65 is a combo amp, without any isolation dampers (like '70's Ampegs had), and it puts out a tremendous amount of 'bottom'. I'm not surprised when the amp shakes the sh-t out of 'em.
In any case, don't forget to 'bias'.
I prefer biasing by oscilloscope to find the crossover point (as opposed to tinkering an arbitrary mA value at the driver resistors, or setting the mA value as high as the tubes will stand (hot)).
I bias a little before crossover (cool). Sounds good, runs cool, and I get some tasty 'brown crunch' at higher gain settings. The downside is that I can't light cigarettes off 'em when I gig.
Enjoy.

Ok, I pulled the tubes out of my 210 sixty-five -- one is a Sylvania EL34 (probably original) the other is a GE 6CA7 (Made in Japan). Any opinions on these GE Japanese tubes or Japanese tubes in general? I know that I should switch out to a matching tube set. Thanks.

Sorry, but I don't have any experience with Japanese tubes, at all.

I bought 4 of these 6CA7EH tubes from the Tubestore, and had them installed by the local amp tech (Bizarre Guitar in Reno). I just picked up the amp, and it now has no volume, and the speakers rattle. All was OK before with Groove tube EL84's, but I had never had the bias set, because I didn't know I was supposed to, I thought I would try these EH's, because that is what I had in the amp when I got it. Now, as a complete amatuer amp guy, I have no idea of what to do. Any suggestions?

An update. I may have a bad power switch. Frustrated, I struck a note, and turned the amp off, for that brief second in the off position where the tubes have some residual power, volume and clarity increased. Unfortunately, this is a very brief event. Frustrated in Reno!

May have a bad tube or two...new ones dont mean working tubes!

Try some different tubes...

Hi All,
I just installed my Eletro-Harmonix EL-34 tubes
and the Electro-Harmonix 12ax7 on my Musicman 210
Sixty-five. Still have to have my amp-head bias
it for me...but otherwise..highly recommended.
I have the Sylvania 6CA7 tubes and Sylvania 12ax7
if anybody is interested.

Hi-
Forgot to mention I bought my tubes at the
Tubestore link above. Excellent price and fast
delivary.

Hi All-
My Sylvania 6CA7 Tubes have been sold.
I love the sound of the Electro-Harmonix replacements that I have installed. Decent tubes
for the money. As time goes on, I will report on
their durability and longevity.

My amp tech just replaced my original tubes in my HD410-130 with these tubes. Hopefully I will have some info to share soon. I am definitely hoping for the best. The original Sylvanias lasted over 30 years and I know I won't get nearly that with anything new. I'll settle for great performance and sound until I have to replace them again.

I'd be interested in the longevity also. I have plenty of old stock stuff but I never use them. I use new simply because we'd better find out what REALLY works- it isn't going to get any better out there.

If the question is do electro-harmonix tubes sound good ,last long ,a monster deal for the money ,the answer is yes.now i must make something clear,i am not using the 6ca7's,i'm using tubes that never came out in a musicman amp,kt88s they sound better then any tube i tried,only one that came close was ruby 6l6str,my amp actully still had the original slyvania 6l6s and to me they sounded kinda boxxy and weird,great clean sound ,but really dark muddy distortion.