[CAJames]

A question please ladies and Gents...

When i have read about microphonics prior to playng with 6c5 series... i assumed it was referred to picking up on desk born noises .. for example, i had some Kenrads that picked up touching the desk they were on let alone a light tapping! THose noises are clearly reproduced in some tubes and i assumed with was the microphonics being mentioned. BUT, with some 6c5 tubes im hearing that when i hit the pause button on the music, there is a slight ringing. And with the headphones set to off position,
you can quite clearly hear the music playing on the "tubes" themselves. In all instances, im referring to sounds after warm up, so its not the "otherworldly" warm up noises im referring to. Could someone kindly explain the correct terms to describe what im hearing? Thanks in advance.

I don't claim any special authority in "tube noise taxonomy" but what you describe is what I'd call microphonics. To me, microphonics means turning any kind of vibration into audible sound, whether that is produced externally (e.g. by tapping) or just from playing music thru the amp. Or put another way, if it isn't the "static" or "frying egg" sound produced directly within the tube itself it is probably microphonics.

 

[Designsfx]

The budget champion of these tubes is the Shuguang 6C8P and surprisingly it is very good sounding and can easily hold its own against the famous names.
Around $5 each on AliExpress including shipping.

I’ve read up on these after seeing this post which many agreed seem to agree with but there also seem to be comments out there claiming they are horrible as well. Are there versions of these or suppliers that are better than others? Are there known fakes out there?

Wondering as well if anyone has given the RCA 2C22 a try- Does it compare wel to the Ken Rad?

 

[triod750]

I’ve read up on these after seeing this post which many agreed seem to agree with but there also seem to be comments out there claiming they are horrible as well.

For me it's easier to find synergy with the Russian 6C2C/6S2S than these Chinese 6C8P. The whole chain has to be taken into consideration.

 

[Designsfx]

Thanks! I’ll check into those. I’ve read positive comments on the RCA’s so I just ordered a quad I found locally. Have you a preferred source for the Russian tubes?

 

[triod750]

I used to have a good source for Russian tubes but he disappeared overnight when Putin invaded Crimea in 2014.

 

[jonchard]

I have played with National Union 2c22s and i felt they were equally as good as most cv6 derivatives... maybe a little more treble strong. The Kenrad 7193s were much easier going to my ear almost inoffensive, but i'm also trying a couple of other sets of kenrads ... when they arrive. I really like almost all CV6 derivatives i have heard, far moreso than 6SN7.

 

[Wes S]

I have been very diligent in my search, and it finally paid off.

Scored this quad of 6S2S 53' Metal Base! These have to be some of the coolest tubes I have ever seen. They have all the cool identifiers we look for with the better NOS tubes, having metal bases, foil getters, bulging glass, and really cool looking codes. Time to see if they sound as good as they look, and find out if they can dethrone my beloved 6S5S. . .

 

[nwavesailor]

So........I have seen this movie MANY times. I think it goes w/o saying that this is just a glimpse of a single quad.
There is no doubt back ups or someone has taken over @Wes S. account..........damn hackers!!!!

On a serious note, they look as clean as any quad and they are 71 YEARS old!!!!

 

[Wes S]

So........I have seen this movie MANY times. I think it goes w/o saying that this is just a glimpse of a single quad.
There is no doubt back ups or someone has taken over @Wes S. account..........damn hackers!!!!

On a serious note, they look as clean as any quad and they are 71 YEARS old!!!!

LOL! These are so damn hard to find, I only have a 1 backup pair so far, and the search continues. . .

It is crazy how they look brand new, with shiny pins and good looking soldering for being so old. Got to love old tubes!

 

[jonchard]

They look stunning!

 

[mordy]

LOL! These are so damn hard to find, I only have a 1 backup pair so far, and the search continues. . .

It is crazy how they look brand new, with shiny pins and good looking soldering for being so old. Got to love old tubes!

Those tubes were manufactured during the height of communism. If you did not produce a great product there were severe consequences…
Did anyone figure out the purpose of the bulging glass?

 

[mvneufeld]

I have a National Union 6F8G and an NU 6C8G, and they sound identical to me even though they have different amplification factors (20 vs 36). Do any of you hear a difference between the 6F8G and the 6C8G? I'm curious because I also have a TS 6C8G, which I really like, and was wondering if it's worth looking for a (much more expensive) TS 6F8G.

 

[mordy]

I have a National Union 6F8G and an NU 6C8G, and they sound identical to me even though they have different amplification factors (20 vs 36). Do any of you hear a difference between the 6F8G and the 6C8G? I'm curious because I also have a TS 6C8G, which I really like, and was wondering if it's worth looking for a (much more expensive) TS 6F8G.

Some people think that the NU 6F8G is the best sounding of that type, but YMMV depending on amp and synergy with other tubes.
Many of these tubes were rebranded and if you learn how to tell which manufacturer it is, you could find better prices.
I have a NU labeled PHILCO and a TS labeled Radiocoin 6F8G tube.
Don’t overlook the all metal single triodes 6C5 and 6J5 tubes - you can still find them very inexpensively but you will need two.

 

[mvneufeld]

I agree that the NU 6F8G is a great sounding tube. I just think my NU 6C8G sounds equally good at half the price and was wondering if more discerning listeners heard any difference. (My ears are 70 years old.) I had a couple of TS BGRP 6F8Gs in the past, but the tinking sound they made when they were warming up annoyed me and I sold them. If you're thinking "What was he thinking?" well, I've sold and then regretted selling plenty of other tubes - Fivre 6C5GTs, Marconi 6J5GTs, and TS BGRP 6SN7s come to mind. Tubes used to be cheaper.

 

[mordy]

I agree that the NU 6F8G is a great sounding tube. I just think my NU 6C8G sounds equally good at half the price and was wondering if more discerning listeners heard any difference. (My ears are 70 years old.) I had a couple of TS BGRP 6F8Gs in the past, but the tinking sound they made when they were warming up annoyed me and I sold them. If you're thinking "What was he thinking?" well, I've sold and then regretted selling plenty of other tubes - Fivre 6C5GTs, Marconi 6J5GTs, and TS BGRP 6SN7s come to mind. Tubes used to be cheaper.

In my old amp i felt that the 6F8G sounded better than the 6C8G but that was in general - don’t have a TS 6C8G to compare with.
However, always trust YOUR ears. My ears are 10% older than yours but I still trust them.
The tube prices have climbed through the skies for popular tubes - the trick now is to use less known but still great sounding tubes to still be able to buy tubes at reasonable prices.
As a rule I only buy and don’t sell - you never know when an old tube relegated to storage is going to shine in a new combination.
And speaking about tubes, I think that a Tung Sol 6F8G is one of the prettiest tubes - the ST beauty queen!