The DC load line assists in establishing the Q point of tube operation. The AC load line assists in evaluating the loading of the capacitor/resistor load of the next stage. Neither evaluate the complete dynamic loading by the speaker and output transformer on the power tube.
The Inductive Load Line evaluates the load placed on the power tube (or transistor) by the output transformer and speaker combination. This is an introduction video which will be followed by 5 more videos to explain the math, theory, calculations and plotting so you can build your own spreadsheet or software analysis program.
Original Work, Copyright 2018 James D. Whiteside, II all rights reserved, For consideration only, no reproduction without prior permission.