Where I did notice a difference (to the better) with the amp added, is scenes where there are large dynamic peaks. Master and Commander’s battle scenes are good examples to demonstrate this.
From all the soundscape chart [thingies] I have seen, scenes like this pump out a lot of sound in the 40-200Hz range. I expect that the power demands would be quite high because this would drive the woofers in your mains quite hard, even with a crossover engaged.
Fred
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