I’m seeing the Belles monos only deliver 112 at 8 ohm. Does it go up to 175 at 4 ohm? When I had the Focus SE, a Modwright KWA150 SE controlled it really well. I did notice a significant loss of bass control with a 50wpc amplifier.
I’d bet the Belles will do alright, but many amps will control the speakers much better.