Thanks for the additional info, Kenny. I suspect that the harshness at 5:30 is the linearity degradation and/or soft clipping that I referred to, corresponding to the amp approaching or reaching the limits of its power capability. If so, along the lines of my earlier comment a gain increase would not help. It would result in the same thing happening, at the same perceived volume, but at a lower setting of the control.
Regards,
-- Al
Regards,
-- Al