Mark I/II:XL:XL+:Release notes4.00Improved power tube plate current vs. grid voltage accuracy. New models more accurately reflect how the response is higher order at lower grid voltages and “relaxes” into a lower order response at higher grid voltages. This improves feel when the virtual power amp is overdriven and improves harmonic content accuracy.Note that existing presets will NOT be affected. Any existing preset will have its local Modeling Version (under the Adv tab of the Amp block) adjusted to its previous value. To use the new modeling you will need to set the Modeling Version parameter to “Latest”. Any new presets that are created will use the Modeling Version selected in the Global menu. For example, if an existing preset was using Q3.xx modeling it will still use Q3.xx. To use Q4.00 you would need to set the Amp block Modeling Version to “Latest”. If you create a new preset and the Global menu Modeling Version is “Latest” the new preset will use Q4.00 modeling.*******************************************************************************