The Reference 6SN7 Thread

[JKDJedi]

Damn, how is that Western Electric 421A+6F8G/VT-99 (Sylvania?) pairing?

It's a great pairing Sennfan.

 

[JKDJedi]

That particular tube is a 1965. The '60's are nice sounding tubes, but bettered by the '50's. Not huge differences between the '51 - '56 rib plates and the '57 - '59 smooth plates, but I think the ribbed versions are still a bit better. Note that the pin soldering on these can be questionable, whether it was poor workmanship or poor quality solder that has degraded over time. On the plus side if you bought them from Upscale you should get a properly working tube out of the box.

So a 1953 Foton might be a good buy.. ?

 

[cebuboy]

Have these on their way, a bit of an impulse purchase from Upscale Audio to use in my Feliks Elise. All Upscale notes is that they are early Russian, found in a cave in Brazil, intriguing but not very specific. Can anyone help me ID their make / year of production?

That is a ‘65 Foton basing from the picture. You can get them for cheap from former Soviet Republics. Great price/performance. The ‘57 and below sounds nicer to my ears but is getting hard to find especially from a reputable seller.

 

[LoryWiv]

That particular tube is a 1965. The '60's are nice sounding tubes, but bettered by the '50's. Not huge differences between the '51 - '56 rib plates and the '57 - '59 smooth plates, but I think the ribbed versions are still a bit better. Note that the pin soldering on these can be questionable, whether it was poor workmanship or poor quality solder that has degraded over time. On the plus side if you bought them from Upscale you should get a properly working tube out of the box.

Good eyes, @bcowen, I missed that entirely. I appreciate it! And thanks @cebuboy for confirming. They should arrive by tomorrow and I'm excite to test them out!

 

[JKDJedi]

It's New Tube Thursday!!

 

[cddc]

A question regarding tube cleansing: is there a coating on the tube pins, or is it just plain vanilla zinc (or steel?) ?

If there is a coating, then using sandpaper or blade to clean pins could be problematic.

 

[JKDJedi]

A question regarding tube cleansing: is there a coating on the tube pins, or is it just plain vanilla zinc (or steel?) ?

If there is a coating, then using sandpaper or blade to clean pins could be problematic.

Thinking it's plain vanilla, I scrape mine with pocket knife.

 

[cddc]

Thinking it's plain vanilla, I scrape mine with pocket knife.

I think so too, but not 100% sure about it.

It's softer than the blade, and can be scraped off easily, so I don't think it's steel, mostly likely it's plain vanilla zinc.

 

[JKDJedi]

I think so too, but not 100% sure about it.

It's softer than the blade, and can be scraped off easily, so I don't think it's steel, mostly likely it's plain vanilla zinc.

That's where the Deoxit comes in, adds a coating

 

[cddc]

That's where the Deoxit comes in, adds a coating

It is a really good idea!

Does the glass bottle one you quoted earlier has a coating component other than de-oxidation and cleansing?

 

[JKDJedi]

It is a really good idea!

Does the glass bottle one you quoted earlier has a coating component other than de-oxidation and cleansing?

The bottle I posted just does the coating, cleaning with alcohol like the others posted (I use a q tip)and scraping with knife works for me for cleaning duties.

 

[LoryWiv]

That's where the Deoxit comes in, adds a coating

Why is adding a coating a good idea...does it improve conductivity / some other sonic virtue?

 

[JKDJedi]

Why is adding a coating a good idea...does it improve conductivity / some other sonic virtue?

According to Deoxit.........YES!

 

[cddc]

Adding sonic virtue - I double it, maybe snake oil does ...

Preventing future oxidation for sure!

But then there is a coating, a coating, a coating. Is the chemical coating conductive? I think it should be conductive.

 

[LoryWiv]

Have these on their way, a bit of an impulse purchase from Upscale Audio to use in my Feliks Elise. All Upscale notes is that they are early Russian, found in a cave in Brazil, intriguing but not very specific. Can anyone help me ID their make / year of production?

Hmmmm, these arrived from Upscale Audio. I'm evaluating their sound and thus far pleased. The caveat is that one of the tube's filaments glows brightly and the other very dimly, a very visible difference. I swapped sockets and it is clearly the tube, not the socket. I did order them in driver / buffer grade as I'm using them as drivers, so didn't expect a perfect match, but the difference visually is striking, not sure what to make of it. Sonically, I do not notice any channel volume imbalance nor extraneous noise from either tube, but wondering if this is "normal" or warrants asking for an exchange.