6SN7 tubes and variants question.

@tomcy6 

I would agree with them. Every system is different. Certain components may work better with a certain tube or cable but an overall system is usually unique unto itself. The more I read that a certain tube is favored by many, it gets my attention and I will often try that tube. Expensive tubes are most often expensive because the market drove the price up. Supply and demand simplicity. How some can be worth thousands for a pair is hard for me to imagine. I would hope they sound very good. I will dabble a bit into the hundreds per pair but not likely to ever hear or own the ones that are in the thousands, just can't justify it. Especially when I am already enjoying tubes that I find for $10 to $50 or so each. OK, enough words just to say that I agree. Thanks.

@immatthewj 

More tube rolling. Moved the National Union Black Glass GT's to the buffer position and put a pair of RCA  Smoke Glass GT's in the line/gain position. Maybe the best combination yet...........maybe. First time I've had 4 GT's in place. Was hoping to have the RCA VT 231's in but one tested with a short so had to look for and buy another. Still waiting for other VT's to be delivered, Raytheons and Sylvanias.

I have been testing everything with CD listening as it has been more reliable for me, having some battles with my vinyl rigs. I think I finally have most of the bugs worked out. Was using some custom made RCA's and ever since putting them in, I've been chasing my tail, trying to figure out what was wrong. I've changed tubes, numerous times, changed cartridges, turntables, everything except the damn cables. Cables and dedicated circuits in the works for next upgrades. 

I took the old Cary PH301 out of the system, thinking it may be the problem. It is getting quite old but to look inside, everything looks like new.........so who knows. Anyway,  using the SLP98 phono section now and was very pleased. First time I'd tried it with this tube combination and with listening to only one side of an LP, I was very pleased. Using Sylvania Gold Brand Gold pin 6189's and Sylvania Gold Brand Gold pin 5751's, which was always one of my favorite combinations in the old Cary. Probably had everything sounding the best that I've heard since owning the 98. Next thing to try is putting the PH301 back in as it should be even better than the 98 phono stage. Probably not by much but who knows. Will post as I make further improvements.

I have quite few years of Rolling 6SN7's where only Half Tube is required in the circuit.

I have used tubes from the 1940's - 50's - 60's - 70's up to ones bought New Stock a Few Years passed.

Tungsol and EH and a Russian equivalent is also classed as a New Stock anf have been used. 

Most recently the Mullard ECC 32 has been appointed a Valve to be a drop in replacement.   

In my system I have got my preferred Valves, but have no issues with using New Valves.

The Russian Equivalent lasted about an hour and is binned, no longer to be used.

That Rusky Critter was not to be sold to anybody as a Valve for a Amp.

There is a Linlai Elite Thread on the Gon, that offers very interesting assessments of experiences had with this Valve. I see as a Valve of Interest.

Do Note: 6SN7 as a Valve is a challenge to find ones that are not noisy, they can't hide from those who know how to find them. 

Sellers typically don't have a discussion about noise in Valves only measurements are the reported info.

High Percentage of Usage Life Valves does not create a quiet Valve

All Valves retained by myself are on par with Manufacturers recommend measurements and are deftly quiet until they are not, non deftly quiet Valves are able to measure in a way that makes them very attractive as a Valve.

Spares not only 6SN7's that a correctly measured and deftly quiet are expensive to have as a safeguard, but are a mandatory idling component for my system. 

Luckily an idling Valve can substantially appreciate in Value.