can be. Continuing with my experiments I have opened the zener switch of the sequel II power supply and .... it has lowered the voltage in the panels by approx 10% and the sound is now brutal, there is bass, there is body there space and there are still incredible and high-pitched voices, it has lost the excess brightness. I am really happy with this change. The next question is whether the same would happen if I remove the jumper from the Sl3, since the Sequel switch eliminates two zeners so the voltage drops but in the case of the Sl3 the jumper deactivates the zeners so the voltage simply It would be out of control and I understand that I had to adjust it with an external variac to achieve the desired effect.