I've been doing a bit of searching and have come up with the Northern Electric 6sn7's and the GE 6sn7GTB's for their claimed low noise and extended highs.
I tested my Sophia's on the ancient tester my brother gave me years ago and found one of them questionable.
I like detail and extended highs, with good bass as well. Read about the TJ Full Music 6sn7's that were described this way. So far I'm leaning towards the NE's and GE's.
I tested my Sophia's on the ancient tester my brother gave me years ago and found one of them questionable.
I like detail and extended highs, with good bass as well. Read about the TJ Full Music 6sn7's that were described this way. So far I'm leaning towards the NE's and GE's.