[adhoc]

thanks for that RobN - would you mind if I added that to my photo stash?

anyway, FWIW, i've seen metal bases with green printing being marked 6SN7A.

 

[Rob N]

No problem

 

[Hirsch]

Quote:

Originally Posted by Rob N One thing I've just noticed,Sylvania 6SN7W's with metal base can also have green printing on the base as well as black

It actually goes far beyond that. Metal base tubes with 6SN7W on the base have been known to have 6SN7A on the bottle. 6SN7A's have been known to have 6SN7GT on the base, etc. I think I've got as many metal base tubes that have inconsistent labeling between bottle and base as those that are in agreement.

 

[Hirsch]

Quote:

Originally Posted by adhoc anyway, FWIW, i've seen metal bases with green printing being marked 6SN7A.

The 6SN7A is actually a slightly different variant of the 6SN7 than the 6SN7W, but I've forgotten what the differences actually are.

 

[adhoc]

Quote:

Originally Posted by Hirsch The 6SN7A is actually a slightly different variant of the 6SN7 than the 6SN7W, but I've forgotten what the differences actually are.

google is my friend.

"There are two versions of the metal base Sylvania, one designated 6SN7A and the other 6SN7W. Often the 'A' version is mislabelled 'W' just to make it more confusing.
The 'A' is a taller bottle and the bottom mica extends just on top of the metal base. It has copper grid posts. The 'W' is shorter and as a result the bottom mica is recessed inside the base ring. Regular grid posts. The tall bottle 'A' is much rarer, but that is truly splitting hairs as they are both extremely difficult to find."

 

[Hirsch]

Quote:

Originally Posted by adhoc google is my friend. "There are two versions of the metal base Sylvania, one designated 6SN7A and the other 6SN7W. Often the 'A' version is mislabelled 'W' just to make it more confusing. The 'A' is a taller bottle and the bottom mica extends just on top of the metal base. It has copper grid posts. The 'W' is shorter and as a result the bottom mica is recessed inside the base ring. Regular grid posts. The tall bottle 'A' is much rarer, but that is truly splitting hairs as they are both extremely difficult to find."

Google may be a friend, but the labels on the tubes are a pain in the butt, as they really don't match the description. If this is accurate, I've got some "A"s mislabeled as "W"s as well as the reverse. I suspect that this description of the differences is not complete, as I believe there were also metal base GT's, making at least three possible Syl metal base variants. There is no real correlation between bottle height and tube type that I've found.

 

[markmaxx]

Quote:

Originally Posted by Hirsch Google may be a friend, but the labels on the tubes are a pain in the butt, as they really don't match the description. If this is accurate, I've got some "A"s mislabeled as "W"s as well as the reverse. I suspect that this description of the differences is not complete, as I believe there were also metal base GT's, making at least three possible Syl metal base variants. There is no real correlation between bottle height and tube type that I've found.

Hirsch, Adhoc,I have a MPX3 comming from Mikhail on Tuesday or Wednesday and I have been reading with much intrest all of the threads on tubes.

Question: So from your quote finding the right tube is going to be hard..But is there also any info as far as price i.e. whats a fair price on xyz tubes so we tube newbies don't get taken to the cleaners.

 

[Covenant]

Quote:

Originally Posted by markmaxx Hirsch, I have a MPX3 comming from Mikhail on Tuesday or Wednesday and I have been reading with much intrest all of the threads on tubes.

MPX3's are evil like that aren't they? I'm planning on buying one too, and suddenly vacuum tubes become an interesting subject...

Got me spending $200 on a matched quad of Hytron 6SN7's too. Evil.

 

[markmaxx]

Quote:

Originally Posted by Covenant MPX3's are evil like that aren't they? I'm planning on buying one too, and suddenly vacuum tubes become an interesting subject... Got me spending $200 on a matched quad of Hytron 6SN7's too. Evil.

I hope the tube rolling will add to the hobby aspect af headphone listening.

 

[Covenant]

Quote:

Originally Posted by markmaxx I hope the tube rolling will add to the hobby aspect af headphone listening.

Or the wallet-crushing aspect. I can already see myself pouncing on the first set of Tung-Sol 6SN7GT's i see, anywhere

 

[Hirsch]

Quote:

Originally Posted by markmaxx Question: So from your quote finding the right tube is going to be hard..But is there also any info as far as price i.e. whats a fair price on xyz tubes so we tube newbies don't get taken to the cleaners.

Tube prices are rather volatile. Further, the right price can depend on a number of factors. Has the tube been fully tested? Is it new or used? Will the dealer stand behind the tube if it fails?

I've got a pair of tube testers that I use to check all tubes that I get. I would be very careful buying from eBay without these. There are some good sellers on eBay, who will provide test results on tubes that they are selling. However, buying from known good sellers is more expensive (once people figure out they are good, they get repeat business).

For 6SN7's, tubeseller.com usually has decent pricing that is reflective of what market price normally is.

I can't really provide a price in dollars for any given tube. For example, TSRP's normally have been going around $200/pr on eBay, but that seems to be rising lately, and $275 would be reasonable. However, I just saw a quad go for just over $200, so who knows? The quad was used (value down), one tube had missing locator pin (value drops), and I don't remember if there were test results posted (if not, another value dropper), so the final price may have been right...or not. If those tubes were near the end of their useful life, then even that price was too high. If the tubes tested near NOS, they were a steal.

 

[Rob N]

Also having an original box (in good condition) can push up the price.
The most expensive 6SN7 type I've seen is the Swedish Standard,a rare tube which goes for $650+ a pair

I've seen apair of 6SN7W with metalbase in original military boxes go for over $400.

 

[markmaxx]

Quote:

Originally Posted by Rob N Also having an original box (in good condition) can push up the price. The most expensive 6SN7 type I've seen is the Swedish Standard,a rare tube which goes for $650+ a pair I've seen apair of 6SN7W with metalbase in original military boxes go for over $400.

Wow:.... I had no idea, that tubes were so expensive. Thanks guys

 

[Len]

Mark, decent NOS 6SN7s can be had for as little as $20 a pair, with many "premium" pairs occupying the $100-150 range. There are some extremely rare tubes like the Swedish Standard that will fetch top dollar, but you really needn't these tubes for great performance (fact is, I don't really like the Swede 33S30).

 

[adhoc]

looking at construction alone, imo the 'premium' 33S30 suspiciously resembles a 5692-type tube.