didn't trader144 say something earlier about why 240volts over 300v? And this was in relation to the sound? This is why I asked my question because it was mentioned earlier how the voltage affects the sound.
My question was about the voltage to the tubes and if there was more room to raise it, not the wall voltage.
MJMP's MDRT installation instructions say to make sure you have the right MDRT for your voltage (US/European) but they can be exchanged with some modification.
More voltage to the tube affects the sound as we all have read. Increasing the tube plate voltage to 240v basically makes the top and bottom amplification tunnel wider and more spread apart so the sound is more articulate and 3D and louder-more gain. If we did this alone and did not change the grid voltage, it would produce less distortion than the original transformer because it is harder for the guitar signal to reach the tube clipping point of the wider amplification tunnel.
But....The tube distortion also depends on the voltage of the grid relative to the anode voltage. This grid voltage is the guitar signal running into the tube that will be amplified by the tube inside the tube amplification channel. A wider input signal is going to hit the tube clipping limits of the amplification channel faster and as a result will create more distortion. Prior to the MDRT the typical way to adjust the guitar signal width (i.e. What the tube will be amplifying) was via trimpot and/or changing a resistor.
In addition to increasing the plate voltage to 240v, the MDRT basically doubles the grid voltage which allows a wider guitar signal to flow into the tube for amplification. Alone this would produce more distortion as it will hit the tube clipping limits faster.
But you have to look at both. While the plate voltage is increased from 190 to 240, or about 26% and the tube amplification channel is wider, the grid voltage is doubled. So the result of the MDRT is more clean headroom, more 3D and more gain and more distortion...but not more of the same type of distortion because the specs are all different and the tubes clip differently.
The downside? At lower plate voltages the tube will clip faster and create more of a brown sound than at higher voltages.
I think I am hearing a different type of distortion at top end levels than when I had the original transformer. It is less digital-like saturation and more of a real overdriven tube.
David