12AT7WA Brimar black plates, GEC A2900 replacement NIB (V117/118)

Beschrijving

Pair: 12AT7 / ECC81 made in by Brimar UK in original boxes

This is a pair 12AT7WA / ECC801S produced by Brimar UK. The tubes have a bended halo-getter, black and copper grid posts, see pictures. The tubes are the military selection; CV4024.The screen print is nice and the etched codes are clearly visible. These tubes show no signs of use and are most likely NOS. See pictures. The early Brimar is highly regarded. Very healthy Tubes with matching systems; see test results. Each tube is wrapped in paper and protected with a cardboard inner liner. This tube belongs to the most popular and sought after 12AT7 ’s ever. This is the longlife, tight tolerance version of the ECC81/12AT7. This tube was made exclusively for governmental institutions and manufacturers of high precision gear. 

Sonics

The acoustic properties of the black plate ECC81 (Brimar production) are outstanding and widely known. I refer to the threads on the web for more information. The preamp valve, low noise, smooth and warm sound with very good vocal presentation, perfect in phono stages. The sound of these tubes is like that of the GEC A2900. These tubes are, like the GEC A2900, remarkable for their air, realism, and seductive warmth, and unfortunately are getting as rare as the A2900 tubes!

 

Test results*

Valve 1 V117	Ia (plate current): Transconductance (Gm): Gas test, Shorts test:	10,0/ 11,1 mA       5,2/ 5,6  mA/V OK	=  NOS =  NOS
Valve 2 V118	Ia (plate current): Transconductance (Gm): Gas test, Shorts test:	9,2/ 9,4 mA 5,1/ 5,3 mA/V OK	= NOS = NOS

  *  For test methods and factory specification read the tube testing page.

 

Short description