I have NOS Teslas in my SP16 which give greater extention and detail without whitening the sound.
These Tubes are almost carbon copies of Telefunkens and the Hong Kong Audio society couldn't split them in sound.
Please note that these are not the current production JJ Teslas.
I also have Herbie Audio Lab dampeners and believe they are a worthwhile upgrade.
Best thing to do is to do some tube rolling to find out which you prefer.
I haven't found profound differences but suptle ones.
These Tubes are almost carbon copies of Telefunkens and the Hong Kong Audio society couldn't split them in sound.
Please note that these are not the current production JJ Teslas.
I also have Herbie Audio Lab dampeners and believe they are a worthwhile upgrade.
Best thing to do is to do some tube rolling to find out which you prefer.
I haven't found profound differences but suptle ones.