Zenith 6cg7 tubes

[Claus1100xx]

Just received these Zenith 6cg7/6fq7 tubes and those are crazy bass machines. I always thought the Jans were the ultimate tubes when it comes to bass.
I thought these tubes were manufactured by GE, but they sound a bit different than the GE's. I'll have to compare them more closely to make sure what the exact differences are, but the bass is definitely the biggest.

Anyone have any experience with these? Or why these sound so different?

WOW, the bass impact with these is stunning.

 

[Hirsch]

Post a picture. Can you tell the country in which they were made? Japanese 6CG7/6FQ7's can have some serious impact. If it's a short-plate tube, that's probably what it is.

 

[Claus1100xx]

will post picture on the weekend, don't have a camera on hand at the moment.

Made in U.S.A.
They are NOS

not sure how I would identify a shortplate tube.

 

[sacd lover]

Quote:

Originally Posted by Claus1100xx Just received these Zenith 6cg7/6fq7 tubes and those are crazy bass machines. I always thought the Jans were the ultimate tubes when it comes to bass. I thought these tubes were manufactured by GE, but they sound a bit different than the GE's. I'll have to compare them more closely to make sure what the exact differences are, but the bass is definitely the biggest. Anyone have any experience with these? Or why these sound so different? WOW, the bass impact with these is stunning.

Zenith didnt manufacture tubes so the tube is rebrand of some other manufacturer. They could be about anything.... but if it has that much bass it could be a tung sol or a USA raytheon.... or even the early RCA 6cg7. The Zenith 6cg7's I have had were actually sylvanias and had noticeably less bass than my favorite RCA clear tops.

 

[Claus1100xx]

haven't heard the raytheons or tung sols yet, but these blow away the bass of the jans. At the same time they are still nice and detailed.
Are there maybe differences when they produce tubes for other companies or do they simply slap on a name and that's about it?

 

[MikoLayer]

sorry Claus1100xx, please excuse my indulgence to jack your thread... I just thought this might be of prime interest to some other members here, so I will ask the question in this thread instead of PM.

sacd lover,
thank you for the reply on the SLAM upgrade, I really appreciate it

seeing how you are the resident tube guru, I would like to ask you for some suggestion on PPX3 tube rolling. My preference for sound is "tubey" - lush midrange and rolled off highs. I am very sensitive to edginess or shrillness, and was never too worried about detail or speed too much; however, I do like airy and smooth highs. Slight midbass hump is something I might tolerate, but bass should be tight and not overwhelming.

So far I have tried RCA cleartops, RCA military tubes with green label, Ei Elites, Electro Harmonix, Sylvania, unidentified JAN tubes with white label.
My favorite combinations are Sylvania in the driving position and Ei's or RCA cleartops for the left and right channels. A RCA cleartop in the driving position sounded cleaner and more extended highs, but somewhat harsher than and not as warm or musical as the sylvania tube.

I see some brands on ebay I never tried before, including Tung Sol (Mikhail recommends these btw), philips and hitachi.

 

[Claus1100xx]

Just realized we have almost the same setup and I am very sensitive to shrill treble as well. No worries, about jacking the thread - at least we can all learn a lil' bit. That's what this place is for

So far my favorite has been the Sylvania with either 2 RCA clear tops or 2 RCA Cryo in the output position.

I bought a couple more tubes and been experimenting a bit and really got to like the GE and 2 RCA Cryo's, but today I finally popped in those Zeniths and they blew me away. So I'm running them on all three positions.
Haven't played around with different gain tubes with them yet.
But the Zenith might have too much bass for you.

The Phillips I have seen on Ebay are all Sylvania relabels. It even says it right on their packaging, so I am not sure about those tubes.

The tung sol are highly regarded by some here on the board. Might be worth a try.

I currently have around 20 tubes, but haven't played around with all of them in various positions yet. Will post more findings as I discover them.
I'd imagine those zenith's would be nice with a cleartop or sylvania as a gain.

 

[MikoLayer]

How are the cryo's compared to the cleartops?
I have been using Sylvania + 2x Cleartops up until recently - in fact, I have just put the Ei elites in last nite, and had them on to listen for a while. To my ears they sound better than my previous setup, you might wanna try that also

 

[Claus1100xx]

yah I never bothered witht the EI, because everybody had only negative things to say. I'll have to try it.

The RCA Cryo is a more detailed Cleartop, but loses some of its bottom end. The spectrum seems to be shifted up a little bit compared to the Cleartop, but not shrill though. I like the detail and sound they give off. Unfortunately I don't have a 3rd cryo to try in the gain position. Anybody tried that yet?

 

[sacd lover]

Quote:

Originally Posted by Claus1100xx yah I never bothered witht the EI, because everybody had only negative things to say. I'll have to try it. The RCA Cryo is a more detailed Cleartop, but loses some of its bottom end. The spectrum seems to be shifted up a little bit compared to the Cleartop, but not shrill though. I like the detail and sound they give off. Unfortunately I don't have a 3rd cryo to try in the gain position. Anybody tried that yet?

I dont like the cryo on gain... I prefer the standard 6cg7. The cryo RCA is the one I find that can get a little harsh in my setup. The Ei is a really good tube, where did you hear the negatives? The Ei 6cg7 is probably the best new production I have heard.. I have always like the GE driving two standard RCA 6cg7's or the RCA driving two GE's.

 

[sacd lover]

Quote:

Originally Posted by MikoLayer sorry Claus1100xx, please excuse my indulgence to jack your thread... I just thought this might be of prime interest to some other members here, so I will ask the question in this thread instead of PM. sacd lover, thank you for the reply on the SLAM upgrade, I really appreciate it seeing how you are the resident tube guru, I would like to ask you for some suggestion on PPX3 tube rolling. My preference for sound is "tubey" - lush midrange and rolled off highs. I am very sensitive to edginess or shrillness, and was never too worried about detail or speed too much; however, I do like airy and smooth highs. Slight midbass hump is something I might tolerate, but bass should be tight and not overwhelming. So far I have tried RCA cleartops, RCA military tubes with green label, Ei Elites, Electro Harmonix, Sylvania, unidentified JAN tubes with white label. My favorite combinations are Sylvania in the driving position and Ei's or RCA cleartops for the left and right channels. A RCA cleartop in the driving position sounded cleaner and more extended highs, but somewhat harsher than and not as warm or musical as the sylvania tube. I see some brands on ebay I never tried before, including Tung Sol (Mikhail recommends these btw), philips and hitachi.

The tung sols are quite good but can be tough to find. I just really like something about the midrange of the RCA 6CG7 clear top. What I suggest to get the sound you describe is a magwire interconnect. Either the magwire original / $36.99 1.0m pair or the magwire ultra v1 / $80 1.0m pair. These interconnects with take the edge of the highs but keep all the good qualities of the sound in tact; in my experiences. This is probably a better and less expensive solution. Despite the inexpensive price the magwires are excellent. I use them on several of my upgraded mpx3's. You have tried most of the 6cg7 combos already and I dont know that you will find anything much different with the remaining tubes. Thats another big plus of the SLAM... you have a whole group of 5687 tube types you can roll in

EDIT: Another solution is to use one of the non oversampling dac's. The slight treble roll off of, for instance, on the original dack v1.2e, would be just what your looking for. There are some very inexpensive non oversampling dac's on ebay or through cattylink.com that I believe would give you just the sound you describe you desire.

 

[sacd lover]

Quote:

Originally Posted by Claus1100xx Are there maybe differences when they produce tubes for other companies or do they simply slap on a name and that's about it?

The rebranders just put their name on the tube. Whatever the tube construction was at the time will be identical for both. I have a tube I am using now called a 7n7. I have this tube with brands like Delco, Emerson, Zenith and Westinghouse... that didnt make tubes. These 7n7's are all Sylvania's.

 

[Claus1100xx]

aahh you're gonna make us upgrade to a SLAM now