I just ordered HD2 Mapletree Headphone amp from Dr. Peppard. He has been very helpful and has recommended the following:
NOS (e.g. GE 5-star) 5751 and a NOS 12BH7A (e.g. RCA)
I was wondering if anyone else has any other recommendations for NOS tubes for HD2 . I could possibly order more to try different sounds.
I'll be using AKG701 headphones and iMod (lossless) as source.
Incidentally I listened to the Earmax Anniversary edition head amp with my AKG701 and they brought them to life.