[TonyNewman]

  ...  Did you get the sylvania tall glass version Tony?  I think those are the older one and supposedly better than the short one.

 
The 7N7s supplied by Woo were Tung-Sols. I can't see any date markings on them.
 
I will plug these in again with the Brimar and give them another run. Perhaps I didn't give them enough hours on the first try - it is hard to keep them in as they suck pretty hard.
 
EDIT - now this is odd - the 7N7s are performing very well with the Brimar. Some slight harshness and microphonics that I hope will disappear with more hours, but they are showing great promise. Not sure why I detested them on the first try - perhaps this was back when I had sucky rectifiers.
 
Anyway, these are not bad tubes at all. Tempted to try them in the WA5, but I don't have a 7N7->6SN7 adapter.
 
If the slight harshness and microphonics fade with more hours these could be winners. I have had them sitting on a shelf, unloved, for quite a few months - in fact I think I came close to binning them after the first listen. Glad I didn't.

 

[MIKELAP]

^

Interesting. I think this going to be a real mystery. Seems that when you order from Langrex it is a lottery with what you get. I ordered brown base on two orders and both times that is what was supplied, but the black plate business is something new.

My first order i was expecting 5Z4GR brown base like on picture i got black base 5Z4G on there site .The second time i ordered i asked for 5Z4GR brown base and thats what i,got .

 

[Oskari]

^

Interesting. I think this going to be a real mystery. Seems that when you order from Langrex it is a lottery with what you get. I ordered brown base on two orders and both times that is what was supplied, but the black plate business is something new.

 
Generally speaking, black-plate tubes are older than grey-plate tubes.
 
Black base versus brown micanol base should make no difference whatsoever, unless yours is an aerospace application.

 

[Stereolab42]

Let the 7N7 hype begin... those 6F8Gs, they are already yesterday's news.

 

[Porteroso]

  Let the 7N7 hype begin... those 6F8Gs, they are already yesterday's news.

I won't have time for a while, but I do plan on picking up a pair of 7N7 adapters. Apparently, regardless of the brand, Sylvania made almost all of the 7N7 tubes out there (NU did make a few), and they are super cheap. It would be very interesting to directly compare them to 6SN7 and 6F8G. Apparently the tall bottle type is identical to the 6SN7, and they are supposedly better than either short bottle version. It seems Sylvania made 3 types. The NU ones are supposedly the best, but I've read in 2 places that they are an unreliable tube. I wonder if it is just people picking up old used tubes, or what. The people that have them working have good things to say about them.
 
edit: Square plates seem to be the best, as opposed to triangle plates. NU made the only round plates.

 

[Krutsch]

  Let the 7N7 hype begin... those 6F8Gs, they are already yesterday's news.

 ... best post I've read, today, except for @mikoss WA2 and tube rolling review.

 

[isquirrel]

  Let the 7N7 hype begin... those 6F8Gs, they are already yesterday's news.

Funny you should say that, these turned up last week.
 

 

[isquirrel]

   
The 7N7s supplied by Woo were Tung-Sols. I can't see any date markings on them.
 
I will plug these in again with the Brimar and give them another run. Perhaps I didn't give them enough hours on the first try - it is hard to keep them in as they suck pretty hard.
 
EDIT - now this is odd - the 7N7s are performing very well with the Brimar. Some slight harshness and microphonics that I hope will disappear with more hours, but they are showing great promise. Not sure why I detested them on the first try - perhaps this was back when I had sucky rectifiers.
 
Anyway, these are not bad tubes at all. Tempted to try them in the WA5, but I don't have a 7N7->6SN7 adapter.
 
If the slight harshness and microphonics fade with more hours these could be winners. I have had them sitting on a shelf, unloved, for quite a few months - in fact I think I came close to binning them after the first listen. Glad I didn't.

Tony,
 
Tung Sols usually take forever to burn in, any chance you could post pics so we can have a look at the construction?

 

[TonyNewman]

 
Tony,
 
Tung Sols usually take forever to burn in, any chance you could post pics so we can have a look at the construction?

 
My camera work blows, but here you go:
 

 

 

[bpcans]

^^^ TonyN, is that a pic of your tube " burn in" WA6 amp? The Tung Sols look pretty cool.

 

[TonyNewman]

^^^ TonyN, is that a pic of your tube " burn in" WA6 amp? The Tung Sols look pretty cool.

 
More than just burn in - it is my PC sound system (toslink->Simaudio 100D DAC->WA6->HD600). I use it to test + burn in rectifiers and driver tubes, but it also gets a lot of head time loving as well. The WA6 is a highly capable amp that pairs nicely with the HD600.
 
This is my first HeadFi setup that was the start of my descent into audiophile + tube madness

 
The Tung-Sol 7N7s are showing some signs of improvement already - I think I can detect some fading of the initial harshness and microphonics (or perhaps it is all happening inside my head).
 
EDIT - not all in my head - these are good tubes that are getting better and better with use. The pairing with the Brimar seems very good, but I will also try the Psvane WE274B replica later for a darker matching.
 
One other thing I have noticed - the 7N7 seems to have a higher output power compared to other driver tubes I have used in the WA6. A bit less of a spin on the gain knob to get the same volume as with other tubes types - not a huge difference, but noticeable.

 

[joseph69]

  One other thing I have noticed - the 7N7 seems to have a higher output power compared to other driver tubes I have used in the WA6. A bit less of a spin on the gain knob to get the same volume as with other tubes types - not a huge difference, but noticeable.

Does the 7N7 use the same adapter as the 6DE7>6SN7 for the WA6?

 

[TonyNewman]

  Does the 7N7 use the same adapter as the 6DE7>6SN7 for the WA6?

 
Nope - different pin arrangement with 7N7 vs 6SN7.
 
Woo sell a very nice 7N7->6DE7 adapter, as shown in the pics above.

 

[Clayton SF]

I see. 7N7 -> 6DE7. It's good to be able to use other tubes with the right adapters.

 

[joseph69]

   
Nope - different pin arrangement with 7N7 vs 6SN7.
 
Woo sell a very nice 7N7->6DE7 adapter, as shown in the pics above.

Thank you.