[Badas]

  i've got one 6F8G TS bg flate plate and like it. In confrontation with NU 6F8G what would you say ?

 
See below:
 

  No rules when it comes to tubes.
 
What sounds good to you is the best tube, no matter how little it costs. 

Very True. I like very cheap power tubes. Russian 6N13's or whatever they are called. Others would frown. However I have tried all the other 6AS7 type tubes and the Russian hits my taste. Problem is getting quiet sets.

  True, but i'm searching about MY ultimate tube. In my dream it will be like a TS 6F8G with more warm mids. That's why i'm asking about NU which they are apparently more colored.

 
Just my opinion. Take it with a grain of salt. Here is my ranking (first worst to last best)
 
Sylvania 6F8G. Not much fun. Similar to 6SN7
RCA Roundplate. Nice tube. Better than RCA 6SN7 type. It beats my 6SN7 Greyglass and clearglass.
RCA Flatglass. Very nice. Better than the 6SN7 type with the same plates. No treble roll like 6SN7. Treble is sweet. Very Dynamic tube. Not much colour.
Ken Rad 6F8G. Not tried. Suppose to be good. Similar to RCA flateplate structure.
Tung Sol 6F8G Flat plate. Not tried. Looks like a Ken Rad or RCA plate structure. I suspect this is a disguise. A classic rebadge or contract make. I could be wrong tho.
Tung Sol 6F8G round plate. Not tried. I will listen soon. I can get my hands on a set to try. From what I have heard the best.
NU round plate. My favorite. Hits my emotional button. Lush. Great midrange. Better soundfield than the others tried. I can't bring myself to try TS RP as this is so good. A whole other level to anything I have heard. I'm stocking up.

 

[TonyNewman]

  True, but i'm searching about MY ultimate tube. In my dream it will be like a TS 6F8G with more warm mids...

 
The NU 6F8G is the best tube I know of that meets that criteria. To my ears the 6F8G TS RP is the better tube technically and is the more neutral of the two. Keeping in mind that the NU is a great tube and is around half (or less) of the cost of the TS RP in 6F8G form, I find the NU to be much better value and more aligned to my tastes.
 
A lot depends on your setup and personal preferences. I use the Brimar rectifier, which is a very close to neutral tube, and plan to use the NUs in my WA5 with a set of Elrog 300Bs. My understanding is that the Elrogs are also a close to neutral sound - so the NU can slot into that lineup very well. With rectifiers and/or 300Bs that bring much more to the sound the TS RPs might be a better fit. It depends on the sound signature you are looking for.
 
My view is that the NU is a superb tube that combines technical excellence with a wonderful warmth and sweetness - perfect for the sort of vocal centric music I generally prefer. For orchestral / classical / jazz styles of music I would probably go for the TS RP, but that's just a personal preference.
 
If you want a driver tube that brings some warmth and lovely sweetness to the sound, perfect for vocals - go for the NU. If you want a more neutral driver, or just want a great all-rounder - go for the TS RP.

 

[Nic Rhodes]

There are other quality round plate 6F8Gs.

 

[Badas]

  There are other quality round plate 6F8Gs.

Please tell.

 

[TonyNewman]

 
Please tell.

 
+1. Some specifics would be helpful.

 

[Nic Rhodes]

There is much cross dressing of 6F8Gs, and in any one make it relatively easy to find multiple types. I have always been a fan of round plate 6F8Gs and like the Tung Sol, National Union and Raytheon round plates. We have taled about the former for 20 years now but the latter have had little press. Who made the latter two is another discussion.... Is it make, age or construction style that makes the difference is a debate I have seen little of.

 

[TonyNewman]

  There is much cross dressing of 6F8Gs, and in any one make it relatively easy to find multiple types. I have always been a fan of round plate 6F8Gs and like the Tung Sol, National Union and Raytheon round plates. We have taled about the former for 20 years now but the latter have had little press. Who made the latter two is another discussion.... Is it make, age or construction style that makes the difference is a debate I have seen little of.

 
Thank you - that helps

 
I look at the internals on 6F8Gs to determine what I am dealing with. The re-branding is so prevalent that the brand on the tube itself is almost meaningless.
 
I have tried several 6F8Gs and the NUs and TS RPs have stood out from the pack. I am a long way from having tried all the 6F8Gs out there, but now that I have the NUs and TS RPs I just don't see the need to keep searching. These are my end-game NOS driver tubes.
 
I think I have tried almost every new production driver tube on the market and they are all rubbish compared to the either of these tubes.

 

[r one]

the sources i use is a violectric dac and balancing act amplifier (with PX4 power output tubes) who give dynamic and neutral sound. I usually listen jazz, ambient jazz and fusion jazz by my TH900 with this set up (but mids are too recessed for my taste, i'm an ath mids fan too : have in the paste w1000x and actually w3k). I've many type of preamp tube : 6F8G TS rp and flate, TS 6SN7 rp, ecc35 mullard and others. My mullard would be my ultimate for mids if it would have tight bass like TS 6F8G and Ts 6F8G would be my ultimate if it would have mids of my mullard....so perhaps NU 6F8G because all tube i've tried i always prefer bass response with 6F8G type instead of 6SN7 type.

 

[gibosi]

  Sylvania 6F8G. Not much fun. Similar to 6SN7
RCA Roundplate. Nice tube. Better than RCA 6SN7 type. It beats my 6SN7 Greyglass and clearglass.
RCA Flatglass. Very nice. Better than the 6SN7 type with the same plates. No treble roll like 6SN7. Treble is sweet. Very Dynamic tube. Not much colour.
Ken Rad 6F8G. Not tried. Suppose to be good. Similar to RCA flateplate structure.
Tung Sol 6F8G Flat plate. Not tried. Looks like a Ken Rad or RCA plate structure. I suspect this is a disguise. A classic rebadge or contract make. I could be wrong tho.
Tung Sol 6F8G round plate. Not tried. I will listen soon. I can get my hands on a set to try. From what I have heard the best.
NU round plate. My favorite. Hits my emotional button. Lush. Great midrange. Better soundfield than the others tried. I can't bring myself to try TS RP as this is so good. A whole other level to anything I have heard. I'm stocking up.

 
Another data point. There exist TS 6SN7GT with the same square top mica flat-ribbed plate design....
 
 

 

[Porteroso]

  There is much cross dressing of 6F8Gs, and in any one make it relatively easy to find multiple types. I have always been a fan of round plate 6F8Gs and like the Tung Sol, National Union and Raytheon round plates. We have taled about the former for 20 years now but the latter have had little press. Who made the latter two is another discussion.... Is it make, age or construction style that makes the difference is a debate I have seen little of.

From what I can tell, the only 6F8G that Raytheon made was a ribbed oval plate? Internals are different from both the NU and TS. I think the TS is the only one with a circular plate, the NU/Raytheons are oval plates. The Raytheons I have sound pretty bad, as well, from what I remember. Maybe I got a bad pair, who knows. I will give them another listen as well, I was listening to so many tubes that night.
 
edit: Giving the Raytheon another listen. They are not bad, definitely not bad. Much more neutral, less midrange, more treble and bass. I will have to listen back and forth sometime. My impressions the first time were that they just were too bright, tinny, and harsh. Just need more time with them to see if my former self was accurate at all Oh, and extremely microphonic. That might have been another reason I hated them.

 

[rosgr63]

 

[Oskari]

 

 
I remember that! But I did not remember that it was more than three years ago in this thread, Stavros.

 

[rosgr63]

Well done Oskari, back in 2009 if I remember well when we were talking about 6F8G's.
 
Time flies......... 

 

[Badas]

Is that the Raytheon 6F8g plate structure?

 

[rosgr63]

Here's the Raytheon plate structure