[Oskari]

My pleasure.

 

[GMF2010]

Quote:

 
That YK is a date code; Oct. 67 like the stamp on the box, I think. DA indicates Mullard manufacture at Blackburn. The tube is unbranded. The British Services were not interested in brands, just the produce. [http://www.tubecollector.org/cv-valves.htm]

 
You know your stuff =)
 
Here's a shot of the top of the original box --
 

 

[dminches]

When testing ECC32s, which tube type should I use for the settings?  My B&K doesn't have setting for ECC32s.  I know the heater is 6, but what about the senstivity to check the gm.

 

[Skylab]

I use the 6SN7 sheet, but you have to use a little math and guess at the right sensitivity setting, and then read the transconductance.

 

[rosgr63]

David some B&K circuits cannot measure a 6SN7 properly.
They use 19mA, whereas the proper current is 9mA.
What that means is they undervalue the 6SN7.
So if a B&K shows a good reading for a 6SN7 you can be rest assured it's excellent.
 
For the ECC32 I would expect a 70% of a 6SN7 value to mean a NOS tube.

 

[dminches]

Stavros, your math works well.  My pair reads 20/20 which is about 70% of 30 which is what I usually get with an NOS 6SN7.
 
Thanks guys.

 

[rosgr63]

Hi David, you are most welcome.
Any chance of a photo please?
 
Do they have the 1185 XXX date codes?

 

[dminches]

Yes.  Here's a photo.
 
What can you tell me about the tube?
 
 
 
 

 

[rosgr63]

This is the military CV181 version, with 1185 A3 date code.
 
Brown base wire getter, very nice sounding tube.
Can I see a slight cathode boil off mark?

 

[dminches]

Mullard, I assume?

No, that is just the light and flash. The tops are clear.

 

[rosgr63]

Mullard

 

[MoatsArt]

Subbed

 

[audiofrk]

this one was supposedly made in italy
 
http://www.ebay.com/itm/391372728223?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

[432789]

is it safe to drop in cv-181 V.E (Mullard) instead of 6SN7 on my DV amp? 

 

[adamaley]

After over four years is there still fervor for this legendary tube? I have a pair incoming to use in an amplifier. Any additional updates from folks who've already posted? Any new owners? I'll be sure to post my impressions once I have them run in.