Wuchak, with the restrictions that you describe(unless a section of shelving can be removed to allow more height), it appears that the M3s would be your best choice. The speakers shouldn't be recessed into the shelf so that the rear ports have a few inches of "breathing room". The front edges should extend a fraction of an inch beyond the shelf to minimize reflections and diffractions from the shelf.


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Enjoy the music, not the equipment.