Most of the time dynamic swings are very short, say a car crash or guys shot, that's a fraction of a second, most avrs CAN handle full power ACD for short dynamic bursts. The only time a steady ACD test is relevant is if you're listening to some godawful pop music in all channel stereo with the dynamic range squashed down to +-3dB, but in all seriousness, most people don't listen to that kind of music much above 85-90dB, which doesn't use a lot of power. It's movies and stuff like classical music that has large dynamic swings, and most all avrs CAN output their full rated power (or possibly even more) for short bursts into all channels.
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