I have three 2A3 tubes unmarked so not sure of manufacturer. I do know these came in a Opera Consonance push pull 2A3 amp I bought. There was four but unfortunately one got broke. I have sold the amp with Sovtek 2A3s so I am offering these three for sale.
Some of you DHT users may recognize the tube make from the photos. I do know these sounded much better than the Sovtek 2A3 and the Sino in the Opera amp. They have a larger glass envelope than the Sovtek and Sino 2A3s. The internal construction looks nice with heavy looking getters, plate, connections and double mica supports at top.
I had these three tested on an Amplitrex 1000 tester and all three test really good. If you can't read the test results in the photo they tested: 82%, 87%, 102% for Emission percent to spec. 96%, 96%, 96% for Transconductance percent to spec. Plate current 49.4, 52.4 and 60.2. Gas negligible and of course no shorts.
Price includes USPS shipping. Thanks for looking.