I put a Tung-Sol 12AX7 in the V1 position of my Mark IV today and my amp just came alive! As much as I love the SED 12AX7's there was just something missing. Both the Tung-Sol and SED tubes have great tone but the Tung-Sols have noticeably more gain. Everything that has been said about these tubes hold to be true; high gain, low noise, low microphonics, warm beautiful tone... simply amazing.
I decided to retube the whole preamp section with the Tung-Sol tubes and they sound great in every position.
I decided to retube the whole preamp section with the Tung-Sol tubes and they sound great in every position.