Guys,
I have a Mapletree preamp, two in fact.
Those who know me ,know I love this thing, things come and go but this thing stays!
I have tried different tubes in this preamp with some success and failures.
The pre shipped with RCA NOS 12sn7 tubes, while I thought the pre sounded great with these tubes it was nothing compared to the Sylvania 6sn7 gta tubes I bought at Vintage tube Services, I got tons of air and dynamics, detail and Prat. These are my standard tubes.
I decided to try the Electro Harmonix gold pin 6 sn7's, nah , gritty sounding and a little cold.
Then Andy shipped me a pair of TungSol 12sn7GT's round plates ..My God these blew away the Sylvania's
So dead quiet, ridiculous amounts of air and detail, extremely black background that revealed all, Tone is Delicious, you can hear deep into the music with no fatigue at all. The most musical tube I have heard yet.
If any one out there uses 12sn7's or 6sn7's these old TungSol's will transform your system, take it to a new level of refinement. I was pissed at how expensive these tubes are, but when I put them in I was even more pissed because I knew I had to have them.