Hi i've just bought a dsl401 sounds amazing but i thought i would check bias so pulled out chasis bias read at pins on amp .620Mv according to various sources like marshall they recommend more like 1.3v so i rebiased to 950 at pins so was my bias really the far out and still net set higher any ideas also the stock tubes are in but amp sounds great they have jj tesla on power tubes any ideas what works well when i need to revalve it regards all great forum