This is a repost for the rolling thread.
I dug around today and found some tubes I forgot I had. There 1972 6n1p-BN. There the finest made tubes I've ever seen. There sounds is so pin point precise, that it's down right scary with the lights off. Very deep punchy bass, and more sub like bass then I've heard from any other tubes. But the treble comes thru as clear as the bass, so there hard on the ears with anything thats not perfectly mastered! So I have a handful of albums that have never sounded sooo perfect, and a truck load of albums that I can not enjoy(unless the volume is very low). The tubes look just like this one in the pic. Notice the fine detail in the insulating spacers, not something you see everyday.
I'm holding true to my findings on that the 6n23p is best for everyday use, with any type of music. The 6n23p does nothing Excellent, and most everything Good~very good.
Listening to the 6n1p-bn as I type this. Talk about lip smacking detail! It's like being there!
The tube in the picture is 6N1P-VE which does not exist outside eBay. The numbers are printed on the tubes using some kind of printer. diyaudio forums mentioned that this could be fake chinese tube made look like vintage soviet. The only 6n1p variants produced in USSR are regular 6n1p and military 6n1p-EV (not VE) version with the getter on top attached on both sides of the internal shield, plus additional mica spacer. The best sounding 6n1p have cccp pentagon sign on them and have carbon plated internal shield (in addition to cathodes). EV versions I've seen have non-carbonized internal shield and they sound somewhat brighter. The screening on original tubes is light bronze color. "OTK" stamps are stamped by hand (it's a QC stamp) after testing the tube and it is usually a rhombus with OTK inside plus the number identifying the person doing the testing. Genuine OTK stamps are usually dark blue lacker (not etching, not white) and are found everywhere on the tube. If you see OTK stamp that looks perfect and appears consistently in the same place - fake - tubes come from surplus storage with no testing done on them.
Edited by djdonis - 6/3/13 at 9:14pm