The Reference 6SN7 Thread

[DimitrisZ]

That price! Disgusting really.

Well.. Apparently I was thinking the same thing, but then I saw a great offer from the seller coming in my ebay inbox, less than half the money than he originally asked. He also accepts returns (thats what he states) so I thought to actually buy them. Still expensive but not that much more than some other offers currently on eBay. I have a genuine pair of 1578 bought about 20 years ago, which I hooked on my amplifiers pretty recently (they stayed all this time in my drawer). The sound is absolutely amazing, I cant believe I didn't use them earlier. Currently using my authentic NOS on my amplifiers and thinking to use those ones on my plreamplifier.

My original indeed look shiny like yours and the ones in the photo look quite rough. Not sure if ours are made out of steel though. When I receive them I will take photos of both, the ones I have and the ones I just bought. By the way when I asked the seller the history of the tubes he was very friendly giving me a lot of details. I saw the low feedback (4) but who knows, he may found these tubes and just made an account to sell them.

 

[turbofeet]

Well.. Apparently I was thinking the same thing, but then I saw a great offer from the seller coming in my ebay inbox, less than half the money than he originally asked. He also accepts returns (thats what he states) so I thought to actually buy them. Still expensive but not that much more than some other offers currently on eBay. I have a genuine pair of 1578 bought about 20 years ago, which I hooked on my amplifiers pretty recently (they stayed all this time in my drawer). The sound is absolutely amazing, I cant believe I didn't use them earlier. Currently using my authentic NOS on my amplifiers and thinking to use those ones on my plreamplifier.

My original indeed look shiny like yours and the ones in the photo look quite rough. Not sure if ours are made out of steel though. When I receive them I will take photos of both, the ones I have and the ones I just bought. By the way when I asked the seller the history of the tubes he was very friendly giving me a lot of details. I saw the low feedback (4) but who knows, he may found these tubes and just made an account to sell them.

Glad they worked out for you.

Maybe he/she was just trying it on.

I do love my 1578s!

 

[Designsfx]

So this is Monday Nights Cheap Tube Tryout! Seen here is a quad of recently acquired 6SN7GTB from Channel Master. I had never heard a CM tube before but I came up with two in my recent swap meet haul so naturally I jumped on the web and found singles so I would have a full quad to use.

Having not heard much about these from others makes for this to be even more interesting as I’m starting with no expectations! I didn’t give these the day long warm up I normally do to let tube settle after shipping- just 30 minutes with the amp and pre and we’re off.

At first listen the sound caught me off guard having just pulled a quad of Raytheon’s out. The Channel Master gave an instant impression of a very clear sounding tube that likes to be driven. Now I don’t know how that compares with use in an amplifier as I’m using them in a dac but that’s what came to mind.

As I type I’m about 2 hrs into listening and things are starting to change a little. This set of tubes produce a very clear and comfortable midrange that provides really good separation of elements without being overly bright or shouty. High frequencies are comfortable so far- I haven’t gotten the impression of sensing fatigue nor have I noticed anything with too much sizzle but I would say that while the high frequency info is crisp and clear the overall extent of its reach follows some of the more neutral tubes I’ve tried.

I feel the bass is something that has still yet to be fleshed out to its fullest. At first listen it felt very subdued compared to the KenRad set I had been previously using. The effect was more punchy than deep (which I tend to prefer) but I am now getting a fuller response now that I’ve put some more time on them. My guess is that (I’m hoping) these will open up more over the next couple of days.

If anyone has opinions/experience with the Channel Master 6SN7 I’d like to hear your opinions as I really don’t see many discussing this tube at all.

 

[Isaacc7]

So this is Monday Nights Cheap Tube Tryout! Seen here is a quad of recently acquired 6SN7GTB from Channel Master. I had never heard a CM tube before but I came up with two in my recent swap meet haul so naturally I jumped on the web and found singles so I would have a full quad to use.



Having not heard much about these from others either makes for this to be even more interesting as I’m starting with no expectations! I didn’t give these the day long warm up I normally do to let tube settle after shipping- just 30 minutes with the amp and pre and we’re off.

At first listen the sound caught me off guard having just pulled a quad of Raytheon’s out. The Channel Master gave an instant impression of a very clear sounding tube that likes to be driven. Now I don’t know how that compares to directly with use in an amplifier as I’m using them in a dac but that’s what came to mind.

As I type I’m about 2 hrs into listening and things are starting to change a little. This set of tubes produce a very clear and comfortable midrange that provides really good separation of elements without being overly bright or shouty. High frequencies are comfortable so far- I haven’t gotten the impression of sensing fatigue nor have I noticed anything with too much sizzle but I would say that while the high frequency info is crisp and clear the overall extent of its reach follows some of the more neutral tubes I’ve tried.

I feel the bass is something that has still yet to be fleshed out to its fullest. At first listen it felt very subdued compared to the KenRad set I had been previously using. The effect was more punchy than deep (which I tend to prefer) but I am now getting a fuller response now that I’ve put some more time on them. My guess is that (I’m hoping) these will tighten up more in some areas and open up a little more in others over the next couple of days. So overall these sound pretty good so far and are a producing a really well rounded sound in my dac/system.

If anyone has opinions/experience with the Channel Master 6SN7 I’d like to hear your opinions as I really don’t see many discussing this tube at all.

Think the Channel Master Tubes I’ve seen were made in Japan. I don’t know which factory made them but I think they were an OEM for a variety of tubes. Sometimes you’ll see Raytheon branded el34 that were made in Japan, supposedly with Mullard tooling. Think that the Japanese and even Korean tubes were mostly made when western manufacturers started to close up shop. I have a couple of Masushita 5ar4 that work really well. I’m not one to think that rectifiers should make much difference in sound but these do seem to be durable unlike a couple of Russian ones I had before.

 

[Designsfx]

Think the Channel Master Tubes I’ve seen were made in Japan. I don’t know which factory made them but I think they were an OEM for a variety of tubes. Sometimes you’ll see Raytheon branded el34 that were made in Japan, supposedly with Mullard tooling. Think that the Japanese and even Korean tubes were mostly made when western manufacturers started to close up shop. I have a couple of Masushita 5ar4 that work really well. I’m not one to think that rectifiers should make much difference in sound but these do seem to be durable unlike a couple of Russian ones I had before.

Yes- these are all labeled as made in Japan as well.

 

[mordy]

Yes- these are all labeled as made in Japan as well.

I have these tubes - very nice sounding and underrated tubes.
Spent a lot of time identifying them. Finally figured out that they were made by NEC (Nippon Electronics Corporation) in Japan.
The date codes are from the 50s.
It is possible that they had tooling from Philips.

 

[Designsfx]

I have these tubes - very nice sounding and underrated tubes.
Spent a lot of time identifying them. Finally figured out that they were made by NEC (Nippon Electronics Corporation) in Japan.
The date codes are from the 50s.
It is possible that they had tooling from Philips.

Is there a document available that shows how to identify production dates? The tubes I have vary between three different number/letter codes on the glass. The changes location from glass to base on on pair as well.

 

[mordy]

Is there a document available that shows how to identify production dates? The tubes I have vary between three different number/letter codes on the glass. The changes location from glass to base on on pair as well.

I am not aware of such a document for these tubes. Usually the codes have symbols for month/year and you have to figure it out.
Many times the months follow the letters of the alphabet starting at A and skipping the letter I which may look like a 1 and the letter O that can be mistaken for a zero (0).
Some companies sometimes start the months on the letter N and may skip Q and perhaps W - the Q may look like 0 and W was used in the tube designation to denote a rugged tube for military use.
Often the year is a single digit and you have to guess the decade depending on such factors as when the tube was introduced, the look of the factory logos that may change over time, and the design of the tube box which usually changes over time. - Often the original boxes are not available, having disintegrated over time.
I have an Arcturus 6N7 ST tube with the date codes N 4
N 4
Finally figured out that the tube was manufactured and shipped out in January 1944.

 

[mordy]

I am not aware of such a document for these tubes. Usually the codes have symbols for month/year and you have to figure it out.
Many times the months follow the letters of the alphabet starting at A and skipping the letter I which may look like a 1 and the letter O that can be mistaken for a zero (0).
Some companies sometimes start the months on the letter N and may skip Q and perhaps W - the Q may look like 0 and W was used in the tube designation to denote a rugged tube for military use.
Often the year is a single digit and you have to guess the decade depending on such factors as when the tube was introduced, the look of the factory logos that may change over time, and the design of the tube box which usually changes over time. - Often the original boxes are not available, having disintegrated over time.
I have an Arcturus 6N7 ST tube with the date codes N 4
N 4
Finally figured out that the tube was manufactured and shipped out in January 1944.

There are date code charts available on the internet for RCA, GE (not the white dots), Telefunken, Tungsram and others.

 

[Designsfx]

I saw this earlier while getting some stuff on Amazon- I was like “Whut?”

 

[LobalWarming]

I saw this earlier while getting some stuff on Amazon- I was like “Whut?”

That's how you spell p-r-o-f-i-t-e-e-r-i-n-g!

A pair of Linlai 6SN7 available for slightly less at: https://www.vivatubes.com/new-matched-pair-2-linlai-e-6sn7-globe-balloon-black-plates-vacuum-tubes/

 

[Galapac]

That's how you spell p-r-o-f-i-t-e-e-r-i-n-g!

A pair of Linlai 6SN7 available for slightly less at: https://www.vivatubes.com/new-matched-pair-2-linlai-e-6sn7-globe-balloon-black-plates-vacuum-tubes/

Even those are too damn high! When did Chi NEW stock 6SN7's get so expensive?

 

[LobalWarming]

Even those are too damn high! When did Chi NEW stock 6SN7's get so expensive?

When 'Murican audiophile marketing departments started offshore myth-building?

 

[g0ldl10n]

When 'Murican audiophile marketing departments started offshore myth-building?

Radiant Selections Reserved for the best.. or something like that..

 

[mordy]

Even those are too damn high! When did Chi NEW stock 6SN7's get so expensive?

Maybe this will make you feel better:
https://www.aliexpress.us/item/3256...id=2024070307292420067487550895160001893320_5
Or apples to apples:
https://www.aliexpress.us/item/3256...c1pzkFgR&utparam-url=scene:search|query_from:
My contention is that all 6SN7 tubes from one manufacturer are the same - just with different print and packaging. And Price.
As far as I know the old NOS manufacturers never resorted to this type of marketing.