That's generally correct. You don't want to have the wrong gain structure, forcing higher distortion for no good reason. Ideally, you want to feed your sub's amp as close to "line level" as possible. If it's +/- 4dB I won't generally mess with it, but if it's more than that it is best to adjust the gain on the amp itself.BTW, @Brian Dobbs , regarding the discussion late in the podcast, the dual volume controls where powered subs are concerned (trim level(s) and the volume on the sub itself) seems to cause a lot of confusion. Maybe @Dave Upton needs to correct me, but my impression has always been that if your playback volume is where you want it, and the trim in the receiver/processor is close to 0dB, then you have things set ideally. If the trim level is getting low, then you need to increase the volume on the sub so that it is brought back toward 0 and if it's getting high, you need to lower the volume on the sub.
Correction, I said that backwards. If the trim level is low, you need to turn the volume down on the sub.