Mcreyn,
what's your basis for writing that the X150.5 will not be sufficient power for the Maggie 3.6/Rs??
I took a look at the 3.6/R impedance curve in the S'phile review. Here is the link:
http://www.integracoustics.com/MUG/MUG/reviews/stereophile_mg36r.htm
scroll down to see the imp & phase plots.
What I see from these plots is that the speaker impedance & phase curves are quite well-behaved & that there isn't much phase shift across the audio band. We are talking +/- 35 degrees max w/ the phase being at 2.5KHz & higher. In the bass frequencies I see that the speaker is a relatively constant 5 Ohm load - very little phase shift in the bass freq.
So, IMO, a Pass X150.5 should be enough. My calc show that you will need about 40W/ch to produce 90dB SPL in your room sitting 10' away. The rest of the wattage will be for dynamics. My calculations show that you have 5dB of headroom for dynamics & I think that's quite good.
I do not know how much current the 150.5 can deliver but current delivery of the amp will have a bearing on how well the amp's wattage increases with decreasing speaker load. If the amp has enough current then you'll get 300W/ch into 4 Ohms & that appears to be sufficient for the 3.6/Rs in your room.
More wattage (along with current to support increase in wattage) is always better but it gets expensive on your wallet!
what's your basis for writing that the X150.5 will not be sufficient power for the Maggie 3.6/Rs??
I took a look at the 3.6/R impedance curve in the S'phile review. Here is the link:
http://www.integracoustics.com/MUG/MUG/reviews/stereophile_mg36r.htm
scroll down to see the imp & phase plots.
What I see from these plots is that the speaker impedance & phase curves are quite well-behaved & that there isn't much phase shift across the audio band. We are talking +/- 35 degrees max w/ the phase being at 2.5KHz & higher. In the bass frequencies I see that the speaker is a relatively constant 5 Ohm load - very little phase shift in the bass freq.
So, IMO, a Pass X150.5 should be enough. My calc show that you will need about 40W/ch to produce 90dB SPL in your room sitting 10' away. The rest of the wattage will be for dynamics. My calculations show that you have 5dB of headroom for dynamics & I think that's quite good.
I do not know how much current the 150.5 can deliver but current delivery of the amp will have a bearing on how well the amp's wattage increases with decreasing speaker load. If the amp has enough current then you'll get 300W/ch into 4 Ohms & that appears to be sufficient for the 3.6/Rs in your room.
More wattage (along with current to support increase in wattage) is always better but it gets expensive on your wallet!