[khaine1711]

To be fair I think I got a bargain on my BGRP. I don't actually know their current market value except Brent listed them at .... $525 per pair.
 
Do you think the RCA grey glass and Ken-rad are worth say ~$180 for each pair?
 
I think I'll need to research more on the Sylvanias - main problem is there seems to be a dozen of them. What are the good ones aside from the mega-expensive 6SN7W metal base? Any "preferred" era when they're made?

 

[Xcalibur255]

They do go for those prices, particularly the Ken Rads, but if you are patient you can get them for less.  Especially if you look for equipment pulls or stuff that tests slightly below new for emission or white box/no box.  The collectors turn their noses up at this stuff but they'll give you the same sound and the same overall lifespan for less money.  Mismatched labels on the tubes is another way to save big bucks.  I got my VT-231 Raytheons for $23 because one of the two tubes didn't have the military markings on it and they weren't a "perfect" match for emission.  I see people listing these tubes for over $300 right now.
 
As for Sylvania, they had more variations than any other maker for sure.  Lots of varied opinions on them too.  Up to the early 50's Sylvania didn't make a bad tube, just different flavors.  Even later vintage GTBs are nice tubes, but anything before the GTA era (basically 1953 or older, though there is some overlap on both ends) tends to be extremely good with a more refined and nuanced sound than the later tubes.  The Ws and brown bases are more lit up in the treble where as the bottom getter T-plate tubes (such as the "bad boys") are a bit more laid back.  You can get the 6SN7W sound without spending $500, you just have to find tubes made on that line that were packaged in regular OEM plastic bases.  They exist but you have to be very careful to pick them out.  The only trustworthy identifier I feel a person can go buy is the extremely heavy getter flash.  It will literally cover the glass almost down to the base.  I've seen these tubes with different types of bases, glass heights, and mica types but they are always "3-hole" T plates and they always sound amazing.  Since they look extremely similar to top getter GTA tubes they don't usually go for big bucks.  This is my personal favorite and the best bang for the buck Sylvania tube to grab IMO.
 
Hope that helps some.

 

[SpudHarris]

Are these worth £140??
 
I have some metal base ones that have similar gettering but these brown base ones have 3 holes.
 

 

 

[Skylab]

Great sounding tubes, for sure, a personal favorite of mine, but they an be had for less. That said, that's a very minty looking pair!!!!

 

[khaine1711]

  Are these worth £140??
 
I have some metal base ones that have similar gettering but these brown base ones have 3 holes.
 

Just a heads up, but there's a seller in Netherland selling several pairs of these for £60+. That particular pair for 140 seems to be from Ireland if I recall correctly.
 
Also are those 6SN7WGTA in those picture the same as the Sylvania 6SN7WGT?
 

 

[SpudHarris]

Just a heads up, but there's a seller in Netherland selling several pairs of these for £60+. That particular pair for 140 seems to be from Ireland if I recall correctly.

Also are those 6SN7WGTA in those picture the same as the Sylvania 6SN7WGT?

Not sure if they are the same. I snapped them up because I already have a few variations with 2 holes.

 

[Rob N]

How many different brands/types of 6F8G's are there?

 

[rosgr63]

A lot actually.
 
I have posted photos of the different plate types earlier on for reference.

 

[rosgr63]

  Thanks.
Yes they look the same.
 
So we have 5 types of 6F8G plates:
 
1.Flat Plates.
2.Flat Plates Staggered.
3.Round Plates Tung Sol Style.
4.Round Plates National Union Style.
5.Oval Plates Ken Rad Style.
6.T-Plates Sylvania Style.
 
Is there more?
 
 

 
Here they are

 

[Dubstep Girl]

Wow

 

[rosgr63]

Actually there may be more.
These are the types I have identified from my own tubes.

 

[SpudHarris]

Great sounding tubes, for sure, a personal favorite of mine, but they an be had for less. That said, that's a very minty looking pair!!!!

Came yesterday and agreed, they are fantastic sounding. I am so taken with them I have already ordered a pair of spares from 1952. I did get them a lot cheaper (£90)....

 

[pne]

  Hi guys, I need some help identifying some tubes I found in the closet. They are marked as Sylvania 6SN7 GTB. Trying to clear out some of my old gear and I'm wondering what these are worth? Also have a bunch of these GE 6SN7GTB tubes. These all have about 150 hours on them, were included with my last tube amp.
 
 
 

 
 
 
So nobody can help me with this? Guess I will just list them for free..

 

[MDR30]

I like Ken-Rad 6f8g's followed by National Union.  They sound similar but the Ken-Rads through a larger soundstage in my Balancing Act.

I am trying a 6c8g Ken-Rad this weekend to see if the increase in gain will affect dynamics.

 

Any news on the 6C8G / Audeze combination?

 

[rosgr63]

   
 
 
So nobody can help me with this? Guess I will just list them for free..

 
They have the GTB style plates with a strong low end.
They are nice tubes.