I have tried listening for hours last night till some time 2 in the morning... I am listening this morning till now...The Amp is barely warm on the top of the transformer... meaning that they have over deigned the transformer, Transformers, Power, Output and Choke are the soul of the tube amplifier. As for the Mullard EL34 tubes, it does not matter caring the life. I will use it till I can find Telefunken or a NOS Mullard. As Mullard EL34 is smoother, Tele El34 is flat and wider in response...from the nature of the nations England and Germany. There is a clever facility to adjust the bias current through 4 trim pots and a Current meter. so that we can tune to the best we can for the working cross point of the output tubes.. This is important for best sonic reproduction. I will go to the market to find some good tubes.. See if I can find it. Yes.. I am using $0.2 a yards loudspeaker. Not damper for tubes and the Amp at all, it will be treated later stage... I am going to find the front tubes., 6CQ7 and 6BH6 from better makers. Oh ,there are a lot of thing to play.. The Bass is deeper and richer...than the WE300B... but the mid range is still lack of the magnetic voice of WE300B... Let me try to pull them closer... That is the fun of Hi Fi...the Fun of Tune-up! WE 300B is like Petrus 1989 whereas 8B is like Angelus 1989!