Captain Obvious here. Well with a new quad set(tested) of these tubes(not Mesa brand($$$), by the way) in this amp, EL34 bias, with the 50 watt setting, using either channel, Tube Rectifier Tracking set "on' and 'Tweed' power switch enabled...this amp is a totally different animal driving a Lonestar 2x12 open back cabinet vs the 6L6 configuration. I wanted to experiment with the amp as an EL34 50 watter...and I am NOT disappointed. I don't use any boost/overdrive pedals(swore those off). It's like having a brand new amp.