I’ve an extra moment and thought I would share the example of why I chose to put 5 mono blocks on my rig, rather than just sit back and let the AVR handle everything.
First, the speakers are rated at 86dB sensitivity; all 5 that are amped with the Outlaw 2200s. I sit ~2m away (little further, but for simplicity...) in a small room, so considering reinforcement, I may only be down 3dB at my seat.
Most times, in stereo listening, I might not really exceed -10, but I have been known to push it depending on the mood and what I’m listening too or watching...
So... 1w at reference level. *shrugs Big whoop.
With an 86dB speaker, in stereo. *yawns
Now extrapolate what happens if I am pushing my system at reference level with all channels active:
Assuming the 70% rule, my AVR cr@ps out just under reference level dynamic peaks @1m.
I don’t trust the 70% rule, and even though Dennis has taken great care in designing these speakers and they present an easy load to drive, why would I leave that on the table?
I chose, for the sake of headroom and good operating parameters, to add the amps for the specific reason of listening to multi-channel programs.
My SACD collection, limited as it is, sounds great when I crank it. And yes, I do sometimes push the bounds of safety. The EU would shut me down as an unsafe environment due to SPL. Much like the orchestras that can’t practice at FFF because it is deemed unsafe!
That said, my calculations are that I need to exceed the available power of my AVR by roughly another 70w just to hit those dynamics at reference level. Account for some additional headroom, say about 250w into 6ohms...
Voila!