WCW/Rich I'm tube shoppingfor my VTL Compact 100 mono's,,any advice will be appreciated,I know that I do not want the JJ's,as I have already lost three,,one was my fault. WCW,, have you experimented with the master bias?After re-biasing mine upon delivery(story in iself,,from MFSS Hi FI),I started tweaking the "master bias" and the sound change was immediately audible, very sweet,,according to Bea from VTL,this is a no-no,,anyway,this weekend I''m retubing them with some second stringers,and I'll let you know the results,,WCW,,are your bias measurment points external or internal?