6SN7 recommendations for SLP 05 Pre amp

Talk to these guys - the exchange rate in the £ is in your favour just now. A range to choose from up to £150.

Watford Valves :: Valves - 6sn7

Sophia Electric also not mentioned thus far. One of the Wammers reported good things from them. Based in Virginia. Sophia Electric's Home Page

 

Have they improved?

BTW, here's a link to a page with a good overview of all the 6SN7 types: PRICE LIST / JAC-MUSIC

 

Short answer: OH YEAH!!!

Longer: advice to draw any conclusions in the first hours is not valid for my pre amp. The difference between now and the first hours is enormous. Magical mid range! Tighter bass. Very pleased.

Been a hard road for my set up over the past two years. New room. Broke a speaker. Electronics failed etc. Finally back on track!

 

I received my 7N7's and the corresponding socket adapters few weeks ago. Being very time poor I only had few hours to listen so far.

The initial impressions are good. Really good. Most of the other 6N7 NOS tubes I tried got few things right, but none of them got all things right.

Sylvania's 7N7's seem to get most of the things right!
Tight, well-defined bottom end, mid-range clarity and depth, relaxed highs.
Sylvania 7N7's are also the quietest tubes I have tried so far. All other tubes exhibited the varying levels of 45-60 HZ hum on the “high-gain” Freya pre-amp.

The one minor gripe I have is with the 7n7 bases. They are not nearly as elegant or easy to insert/handle as 6n7 ones. To avoid the risk of damaging the tube or base pins great care needs to be taken when inserting the tubes into their base/adapter.

Having said that. These will most likely become my default tubes. Hope this finally puts the stop to an expensive journey of trial and error with 6N7 NOS' tubes.

Thank you once again for bringing them to my attention.

Regards

 

Glad it worked out for you. Now that you mention it, I do remember that inserting the pins into the adapter was tricky ... But I think the adapter itself looks rather cool, actually

 

Point of Interest -
The 7N7 tubes were designed solely for military use in bomber planes during the early stages of the cold war. Their bases include a "locking" feature, since many of them were mounted upside down and being locking they wouldn't vibrate out during flight. Later the NATO phased out vacuum tubes in favor of "solid state" equipment, while the Soviet Union continued with tubes. The Soviets felt that tubes were more resistant to a static charge from a possible nuclear blast than solid state electric items might be. Which is why current day Russian still has a tube manufacturing industry and we haven't for many years. . . . . If you want to try another variation, look for the 7AF7 tubes, they are in the same boat. Most of these tube were made by the same couple of manufacturers regardless of how they are labeled.