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Old 10th November 2007, 07:31 AM   #1
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Default G.E. 6CA7/EL34 - any good?

I've ran across a chap who has a few of these, BNIB, and was wondering if they would be worth the money($240/quad), and how they compare to the Mullard EL34?

Give me your opinions, people, this enquiring mind want's to know...

Cheers... G
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Old 10th November 2007, 09:04 AM   #2
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Hi,

http://search.ebay.ca/GE-el34

I'd say no on that price

Cheers!
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Old 10th November 2007, 08:39 PM   #3
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Yeah, but what will they sell for? Those auction's have a lot of time left to run.

Basically, these GE's are being sold at 30 ($60) each, NOS-BNIB. With used Mullards goung for 25-35, and NOS going for 50+ (I've seen matched quad's fetch 300+), if the GE is a decent tube, I'm interested to know.

Anyhoo, Cheers... G
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Old 10th November 2007, 10:17 PM   #4
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The GE tube is great in guitar amplifiers and better than ok in the few tube hifi amplifiers I've heard them in. IMO there are current production tubes from EH and JJ that cost a lot less and probably sound a bit better in most amplifiers.
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Old 11th November 2007, 01:06 AM   #5
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Since I've not seen this auction I'm not sure but there's a chance these tubes are actually Mullard or Amperex. You call them 'brand new in box" but GE hasn't made tubes in years, so they're perhaps 'new old stock" (NOS). If so, and depending on the vintage, they could have been made in Europe and rebranded here by GE. I've seen (and owned) many examples of these with both brown and black bases from GE and RCA. It was a common practice to import and rebrand these in the 70's and 80's. They even said made in Great Britain (Mullard) or made in Holland (Amperex) in small print somewhere on the glass. This also applies to the 5AR4 as well as some others.

Victor
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Old 11th November 2007, 02:54 AM   #6
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Well, they're not in an auction. They are NOS, boxed fat bottle GE 6CA7 (with the obligatory /EL34), circa mid-70's manufacture (iirc).

As is, after further research on various forums there seems to be a general consensus emerging that, compared to mullards, these show a slightly deeper, more solid bass, and a slightly less 'forward' presentation.

To try, or not to try...

The truly difficult part is deciding between picking up a quad of these, or picking up a quad of EH 6CA7 & a quad of jj KT77 for pretty much the same price
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Old 11th November 2007, 03:33 AM   #7
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Ok, if they are the fat bottle shape then they are not the European imports I thought they might be. All of those that I have seen were the regular slim style. Personally I don't subscribe to generalizations regarding how one brand of tube sounds compaired to another. It more depends on the circuit it is used in and how it is set up to operate. And getting eight tubes instead of four seems like a better deal to me in this case.

Victor
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Old 11th November 2007, 10:11 PM   #8
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Quote:
Originally posted by HollowState
Ok, if they are the fat bottle shape then they are not the European imports I thought they might be. All of those that I have seen were the regular slim style. Personally I don't subscribe to generalizations regarding how one brand of tube sounds compaired to another. It more depends on the circuit it is used in and how it is set up to operate. And getting eight tubes instead of four seems like a better deal to me in this case.

Victor
One other thing to bear in mind is that the fat bottle GE 6CA7/EL34 is actually not a pentode at all, but a beam power tetrode, and will sound different than your garden variety EL34. These were good tubes, but it is hard to know what to advise, if you are curious and willing to risk the money these might be worth trying in your amplifier. A low hours quartet should they not float your boat should be resalable on eBay for a good percentage of what you would pay for them.. Of course in any subsequent sale YMMV...

I guess I will respectfully disagree with Victor's statement above - in very careful listening tests I found there were obviously audible differences in the output tubes I was listening to. Nothing else was changed - and there were sometimes subtle, but measurable differences in both spectra and overall thd%. All tubes were matched and operating currents were as near to identical as I could make them. I'll also add that the best sounding tubes weren't necessarily my pet favorite of the moment either.. (The amplifier in question was a heavily modified ST-70 with my driver board kit installed.)

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Old 12th November 2007, 01:02 AM   #9
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Kevin said:
Quote:
I guess I will respectfully disagree with Victor's statement above
Hummm, I think you misunderstand my meaning, or perhaps I didn't state it properly. I wasn't saying that different brands or styles of a tube cannot sound different in a given amplifier. Clearly they can and sometimes do. No, it is the broad generalization, the painting with a wide brush, that all tubes of a particular type will have a propensity for a certain characteristic sound in most amplifiers as per drgonzo2's findings from other forums. This is what I basically disagree with.

There are simply too many variables to be accounted for before stigmatizing a tube as less pleasing. What sounds good in one amp may not sound quite as good in another with a different topology and/or operating point. And I know I'm not telling you anything you don't know. I just want to make this point. A prime example of this can be read somewhere on tubelab's site where he raised the current (operating point) in the output tubes and the sound went from mundane to "it rocked".

If you accept this premise, then we have no disagreement at all. I hope this clears it up.

Victor
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Old 12th November 2007, 03:28 AM   #10
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Quote:
Originally posted by HollowState
Kevin said:


Hummm, I think you misunderstand my meaning, or perhaps I didn't state it properly. I wasn't saying that different brands or styles of a tube cannot sound different in a given amplifier. Clearly they can and sometimes do. No, it is the broad generalization, the painting with a wide brush, that all tubes of a particular type will have a propensity for a certain characteristic sound in most amplifiers as per drgonzo2's findings from other forums. This is what I basically disagree with.

There are simply too many variables to be accounted for before stigmatizing a tube as less pleasing. What sounds good in one amp may not sound quite as good in another with a different topology and/or operating point. And I know I'm not telling you anything you don't know. I just want to make this point. A prime example of this can be read somewhere on tubelab's site where he raised the current (operating point) in the output tubes and the sound went from mundane to "it rocked".

If you accept this premise, then we have no disagreement at all. I hope this clears it up.

Victor
Hi Victor,
That makes things a lot clearer, I think we basically agree since you have rephrased your previous comments. Would tend to jibe rather well with my experience. As you probably noticed my remarks were predicated to one very specific amplifier design, and like you I have noted that the results aren't really that "portable" except in very extreme cases. (Mostly bad.. LOL)

FWIW The best sounding tubes in that amplifier were a quartet of Shuguang EL34 at a time when their quality was so bad that they all failed within about 50hrs.. We used to call them fire crackers for their propensity to blow up without warning - all remaining samples went into the trash..
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