[Synthax]

How do the RP compare in sound to FP version of 6f8g TSs?

 

[Seamaster]

Buenos_Aires Radio,

as Skylab says is a very good supplier. He packs carefully and the matched 4 x Syls I bought were quite clearly unused NOS.


I also bought 5 x Tung Sol RPs from Hong Kong, used but tested strong. I have a question here - one of the Tung Sol is a little wobbly between glass and base - what glue should I use to make this secure.


So who bought the 2 x National Union tubes which sold last night on Ebay/US. I was tempted but refrained.

Just Google search, there is glue for audio tube repair.

 

[Black Stuart]

Thanks seamaster, I will take a look on ebay as I still have that tube.
 
A very old thread this one but still relevant to me. The RPs are for me still head and shoulders above any other 6F8G or indeed any other type of pre-amp tube. Having both a hybrid h/amp and power amp using for the pre-amp section, driver + two output tubes I cannot even imagine using any other driver than the Tung Sol RP with o/put 1578s.
 
Together they create a whole sound that for me is the end game. The sheer emotion of the Tung Sol mids is incredible and the top and bottom of the 1578 are unbeatable. I just wish I knew this about 20 years ago, my stash would have cost me peanuts and I would have saved a lot of money not spent on inferior tubes.
 
Once again many thanks to Skylab for giving us all the griff on these tubes.
 
What I don't understand is why with all the hugely increased knowledge over materials and the availability of robotics and spotlessly clean manufacturing spaces that can be created easily today that no one is making these designs from new. Patents are out of date so that's not the reason.
 
I can easily understand why for example that those fabulous Japanese d/d superdecks are'nt being built today - cost.

 

[Skylab]

Vacuum tubes require chemicals that aren't allowed in manufacturing in Europe or the U.S. anymore. That's one reason why they're only made currently in Russia and China, although tubes really never stopped being produced in either country as they remain in use in their respective militaries.

 

[Synthax]

  How do the RP compare in sound to FP version of 6f8g TSs?

??

 

[jamato8]

 
??

I hear great detail and in general a cleaner frequency response with the round plate. The idea is that from the grid the electron flow distributes to the plates better than the flat plates or square plates. I notice the same improvement in Tung-sol 6SU7 black glass that has round plates, as in the 6SN7 round plates from Tung-sol. I have 1932 mesh plate 27 tubes that have the mesh plate round and notice the same thing with them vs a flat plate. 

 

[Synthax]

Thank You very much for this comment. I have nearly the same observations having both for tests. To me round/oval plates offer also slightly deeper bass and more lower midrange focus.

But both with excellent detailing

 

[adamaley]

Can anyone comment on the difference between the TS 68FG flat plate vs. ladder plate vs. round plates?

 

[cobyatch]

Can anyone comment on the difference between the TS 68FG flat plate vs. ladder plate vs. round plates?

Haven't had the chance to try a flat plate, but the round plate TS 6F8G is highly superior to the ladder plate. The ladder plate is mediocre at best, whereas the round plate is top tier and probably my favorite tube at the moment. It's really a night and day difference; the round plate provides a cleaner and more detailed sound, fuller (and tighter) sub-bass and is more extended in the highs. Slightly larger soundstage than the ladder plate as well. Mine is not the version labeled VT-99, however I'm sure that this one provides the same experience as others have reviewed before.

I have a couple of RCA tubes that have the same ladder, getter, and smoked glass design as the ladder plate TS that sound very similar so I think it may have been a shared design or same manufacturer. Interestingly, I do have a clear glass RCA with the same ladder and getter design I would rank very close to the round plate TS, having better mids but not as much slam and treble extension.

 

[Gallic Dweller]

I have at least 4 different 6F8G tubes and the Tung Sol RP are simply the best. The Round Plate tubes of different types are always superior aka the Tung Sol 6SL7 is an example. I combined the Tung Sol RP 6F8G as driver tube with the Russian military 1578 x 2 as o/put tubes in the preamp section of a hybrid h/amp and the combo is an end game. Sadly these RP tubes have surged in price.