From the Audyssey FAQ:
http://www.audyssey.com/technology/faq.html#overdriving
Is there a danger of overdriving the loudspeakers by using MultEQ?
No, MultEQ filters are calculated by taking into account the capability of the loudspeaker and the overall gain structure of the system. Limits in correction are imposed at each frequency to prevent the loudspeakers from being overdriven.
So according to Audyssey at least it is not an issue. Also I’m not sure a sub like the EP500 would be in danger either because wouldn’t it’s own DSP chip prevent it from being overdriven or am I mistake about how that works.
How well does MultEQ work at low frequencies?
This is one of the unique strengths of MultEQ. Room correction methods based on parametric equalization do not have enough bands or processing power to apply correction in the bass frequency range. MultEQ uses a unique implementation of FIR filters that achieves very good resolution at frequencies below those that standard FIR filters can reach. The resolution of the MultEQ filters varies with frequency and this allocates more of the filter correction power where it is needed the most: in the lower frequencies.
On of the reasons Audyssey recommends all speakers including full range be crossed over at 80Hz is because their filter on the LFE channel is suppose to be much finer than the low frequency filter on the other channels.
I’ve your read any of my posts you’ll know I’m not an Audyssey fanboy or even a fan for that matter. However, I can say with my current implementation of Audyssey on my Onkyo 3007 the bass from my EP500 is noticeably improved with Audyssey on in the one direct comparison I’ve made.
