[nwavesailor]

  When I ordered my Raytheon 6F8G, I got it in a bundle together with a National Union 6F8G too. Never bothered with the latter...until today.
 
What a beautifully sounding tube!
I like it better than the Raytheon. A few words that could describe the flavor of the sound: very articulate bass lines (bass guitars sound splendid), great clarity in the mids, and one the largest soundstages I have found in tubes (comparable to the Visseaux).

Another oval plate tube! I have used the NU and Tung Sol 6F8G in the output of a CD player with great results. Do you find the NU 6F8G loses a little top end to the Visseaux 6J5G?
 
Most of the NU and TS 6F8G's I have are also pretty microphonic but I still use them and like them very much. I guess I better give the NU and TS another (longer) try in the amp!

 

[Tunkejazz]

 
Another oval plate tube! I have used the NU and Tung Sol 6F8G in the output of a CD player with great results. Do you find the NU 6F8G loses a little top end to the Visseaux 6J5G?
 
Most of the NU and TS 6F8G's I have are also pretty microphonic but I still use them and like them very much. I guess I better give the NU and TS another (longer) try in the amp!

Actually not! This one extends beautifully in the top end without ever becoming harsh. I will go back to the Visseaux later to get a better feeling. But yes, it is microphonic :-S

 

[Mechans1]

As long as there is no feedback loop, microphony is not a problem, unless you drum on your tubes when they are playing in an amp.  Some say a little microphony creates a more spacious sound.  I was very upset when my vast collection of 6SN7s turned out to be filled with microphonic tubes I knew that 6SN7s had a reputation for being microphonic especially the older  variants.. I discovered the microphony in my tubes when I went from using them as drivers in an integrated  to amplifier duty in a preamp.  
Fortunately I learned that if I didn't knock the preamp or the tubes themselves, they worked great. Now I don't care as much, except that it does devalue the tubes a bit, but I wasn't buying and selling.  I just bought and kept.  After this tax season is over I might be more adventuresome and get some adapters to hear what other related tubes can do.
I am surprised that you didn't think the NU would be a really good tube.  What had you heard about Raytheons that drew you to them?

 

[Tunkejazz]

Well...I swapped to the Visseaux and listened for an hour or so.What can I say. The NU 6F8G is very good. The Viss are better.
The sound is more vivid and clearly punchier in the bass.
I hate this. Every time I think I found a tube that is  "as good", I switch back and I always prefer their sound.

 

[nwavesailor]

  Well...I swapped to the Visseaux and listened for an hour or so.What can I say. The NU 6F8G is very good. The Viss are better.
The sound is more vivid and clearly punchier in the bass.
I hate this. Every time I think I found a tube that is  "as good", I switch back and I always prefer their sound.

Yep, I have quite a few tubes that are ALMOST as good............then I put the Visseaux back in and go................. AHHHHHHHHHHHHHHHHHH!!!!!!!!!!!
 
Not day and night, but the 'V' is very special tube that has me under it's spell. The Brimar's (in my short audition) were very close but, IMO, just a hair short as well.

 

[joespride]

Ok, 6C5 certainly seems more spacious (It is a bit microphonic when coaxed) I really like the open spaciousness of the sound, I dont know if I would say it has a larger sound stage
 
This brings to mind a question.  If you find a pair of tubes that you really like (though not technically as good as Viss) which would you opt to keep
 
1. Very pleasing almost holographic and considerably lower price
 
2. Very pleasing Technically Better but cost about 4 times as much
 

 

[joespride]

Mazda 76 sounding very much in line with Brimar 6j5, also they are pretty quiet Looking like Keepers,  
 
The 6c5 while more spacious it is also thinner lighter on bass. This tube may appeal to someone looking for soundstage it is certainly more open.  The 6c5 also seems to pull more detail ?

 

[connieflyer]

While I had your tubes originally, the Viss's were slightly better than the others, the 6j5's 6c5's and the 6L5's.  I repaired an adapter I had and while waiting for my Elise to come in, (a few months) I picked up a pair of 6L5's and 6J5's, the five's were Sylvania GT, and I prefer those to the 6l5 and the 6c5. I had those tubes and rolled them all back and forth, and found the Viss's to come out on top, followed by the Sylvania 6j5's.  The Sylvania's I am using now are working quite well.  So much so I do not miss the 4 Viss's as much as I thought I would. It will be interesting to be able to compare the Elise to the Ember directly.  Hope you enjoy your tubes Joe, you have a good set.  I bought the 6C5's mainly because they were the precursor to the 6j5, and I really liked the way they looked, I just never thought they were as good as the others.  Just my opinion, and they were new tubes, so maybe they were not burned in enough.

 

[DecentLevi]

PART ONE OF MY COMPARISON OF ZENITH 6J5 AND VISSEAUX 6J5​

PHOTOS​

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As you can see, there appears to be two slight variations of Zenith 6J5 cooling fins​

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Difference in mica shapes​

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Major difference in size / shape of plates​

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The Zenith is slightly taller​

 
 
 
Sound impressions coming in part two...

 

[DecentLevi]

COMPARISON OF ​

ZENITH 6J5​

 AND ​

VISSEAUX 6J5 - PART TWO​

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SOUND IMPRESSIONS
 
OK guys here's my impressions of the Zenith 6J5 compared to the best of my other tubes, especially the Visseaux 6J5... Let me just start out by saying: I have spent the past 3 hours since I've heard them trying to calm down enough to be able to explain this to you... make sure your chair is steady before reading this so that you don't fall over

. Without further ado, here we go:
 
From the first few seconds with the Zenith tubes, I was in total disbelief. The biggest 'What moment' I can remember experiencing with home audio yet (excluding meets). Immediately I noticed there's something completely surreal going on here.

 The sound / performance of these Zenith 6J5's were truly good enough to break me away from a deeply involved project I was working on to do some in depth comparisons and write up this review for you guys. And they give me a big smile every time I listened with them, even enough so I was still smiling long after the music stopped. I kid you not.
 
Firstly, curious to see how the buzz fares to the Visseaux 6J5, I cranked up the volume to max with no music playing with my lowest impedance headphones plugged directly into the Ember, and - WOW!!! Absolute 99.9998% 'humphrey'! I only heard the faintest of the faintest buzz, and and levels so insane I would be absolutely guaranteed to never notice it at any normal listening level. At this level, my Visseaux would be buzzing like a hive of bees. So there you have it, your 6J5 buzz solution without the need for the jail-cage / bug zapper / aluminum foil wrap thingy that you may need for the Visseaux. 

 

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This lousy photo doesn't begin to do justice. It looks alarmingly better in real life​

 
 

Dynamics: Without a doubt, the best dynamics I can remember getting out of a tube.
compared to the Visseaux:          harder hitting and more pleasing
compared to the GE 6SN7 GTA:    slightly harder hitting
compared to the Ken-Rad 7193's: noticeably better
  The dynamics are hard hitting with great slam / impact, making it especially great for electronic music / pop.
 
Mids: Very lush, audiophile-grade sound. Good enough to make we want to eat it, if it were possible. 
compared to the Visseaux:          more lush and full
compared to the GE 6SN7 GTA:   more lush
compared to the Ken-Rad 7193's: slightly lusher

  I do have to mention however, that the lushness of the Zenith 6J5's is a double-sided sword. On one hand, you get that velvety lush sound, which makes it especially good for acoustic / percussive music such as rock and jazz - it sounds so glorious with these genres, in fact, that you may very well be tempted to invite a neighbor over for a listen! But on the other hand, with about half of the electronic music genres I tested them with, I began to feel like something was overdone. After some critical listening / comparisons, I realized that's because the Zenith 6J5's add quite a bit of harmonic distortion. That's the euphonic tube-saturation that you generally get from tubes. The above comparisons showed me that the GE 6SN7 and Ken-Rad 7193's sounded noticeably more clean / lifelike in the mids, while the Zenith's sounded more colored and musical. Other tubes end up sounding somewhat stale in comparison, especially the Visseaux. This is not necessarily a bad thing, but it all comes down to preference and to the music that's playing.
 
Soundstage: This, along with the dynamics, I will tell you are without a doubt it's strong points!!! Completely immersive, immaculate 3-D experience!!
compared to the Visseaux:          at least 15% bigger, and with more lifelike imaging
compared to the GE 6SN7 GTA:    at least 50% bigger
compared to the Ken-Rad 7193's: at least 20% bigger

   Yup folks, at least with my pair, the Zenith is king of soundstage out of all the several dozen tubes I've tried on the Ember, including 6DJ8, 6SN7, 7193, and 6J5 classes. There's also something really uncanny with the imagining, it's as if you are closer to 'being there', right in the scene of the recording with these tubes. Speaking of imaging, the instrument separation is spot-on: cohesive and pleasing. Other tubes sounded quite 'closed in' compared to the Zenith. They give a great 'out of your head' experience.
 
Frequency range (FR): I would say that overall, these tubes all had about the same FR, with slight variances
compared to the Visseaux:          same
compared to the GE 6SN7 GTA:    same, but the GE has slightly fuller mid-bass body / definition
compared to the Ken-Rad 7193's: the same, IIRC

 
Neutrality / tonality: In short, I would say the Visseaux is the most refined in this area, while the GE is more neutral / dry and the 7193's are off kilter. As for the Zenith, like the mids, they are also slightly off kilter. That is to say, that while it sounds quite pleasing, it's more on the 'musical' side. 
 
As mentioned in the mids section, the Zenith has a sound slightly on the euphonic side of neutral. This, and the top-notch dynamics make it sound good for around half of the electronic / pop music I tested it with, but sometimes a little too lush for my tastes. On the other hand, this lushness makes them, IMO to be world-class performers for acoustic leaning music like jazz / rock, and perhaps classical too.
 
Finally on the comparison of Zenith and Visseaux 6J5, I think it's too early to tell the winner. With the Zenith, my ears were telling me they are better, and visa-versa with the Visseaux too. But overall I am slightly leaning toward the Zenith due to the soundstage and impact that are absolutely world-class. I believe with further burn in (prob. at least 140~ hours) the Zenith could very well surpass the Visseaux on all fronts; and that it already has the Visseaux beat on multiple fronts.
 
Disclaimer: YMMV depending on the condition of your Zenith and headphones used. My Zenith tubes were tested in great condition at at 86 & 90 reading (out of min. 65), and my testing was done mostly with the Ember as a preamp to the Liquid Carbon amp in balanced mode with the HD 650 headphones; and also some direct usage with the Ember - and I will tell you the Zenith tubes are no slouch at all when used directly from the Ember.
 
In a word, I call the Visseaux "sublime", and the Zenith a "sonic masterpiece".

 

[nwavesailor]

 

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In a word, I call the Visseaux "sublime", and the Zenith a "sonic masterpiece".

Nice work, DecentLevi!
 
The Zenith's were likely produced in far greater numbers than the Visseaux. Looking at 'sold' listings on E-Bay, pricing for nicely matched pairs were far less as recently as December

 

[HOWIE13]

Well done DecentLevi-great comparisons and the Zeniths are selling just now for about the same we paid for the Visseaux a few months ago.
I'm not at all surprised by your findings though. A week or so ago I posted that the Zenith 6P5's, which preceded the 6J5's, were excellent in Ember, very similar to the Visseaux 6J5's but I didn't do a thorough comparison like you have done.

 

[DecentLevi]

Thanks much Howie! I just do it to share the love - I really hope someone else takes my lead to get to experience it's sonic wonder - one that is growing on me! And I'm sure someone can find a lower price than eBay by scouring the web

 

[HOWIE13]

  While I had your tubes originally, the Viss's were slightly better than the others, the 6j5's 6c5's and the 6L5's.  I repaired an adapter I had and while waiting for my Elise to come in, (a few months) I picked up a pair of 6L5's and 6J5's, the five's were Sylvania GT, and I prefer those to the 6l5 and the 6c5. I had those tubes and rolled them all back and forth, and found the Viss's to come out on top, followed by the Sylvania 6j5's.  The Sylvania's I am using now are working quite well.  So much so I do not miss the 4 Viss's as much as I thought I would. It will be interesting to be able to compare the Elise to the Ember directly.  Hope you enjoy your tubes Joe, you have a good set.  I bought the 6C5's mainly because they were the precursor to the 6j5, and I really liked the way they looked, I just never thought they were as good as the others.  Just my opinion, and they were new tubes, so maybe they were not burned in enough.

That's a very long time to have to wait for your new amp.

Do they ask you to pay in advance as well?

 

[HOWIE13]

  Thanks much Howie! I just do it to share the love - I really hope someone else takes my lead to get to experience it's sonic wonder - one that is growing on me! And I'm sure someone can find a lower price than eBay by scouring the web

I really didn't know much about Zenith as it's not big in Europe but it seems they invented the wireless remote control and they have very good provenance.