[quote]Also more seiriously, are they all the same size?[/quote] Yes, ish. The original 12 Halos were 30,000km in diameter but could only fire in one direction. These Halos were all destroyed, save for the ring that came to be known as Installation 07 which was pretty much smashed into a planet to shed away a load of its mass so it could go into slipspace. The final 7 Halos are all 10,000km in diameter.

[quote]Halo: Does it blend?[/quote]If you've got a neural physics blender larger than 10,000km in diameter, then yes. [quote]Also more seiriously, are they all the same size?[/quote]No. Initially, the Halo rings were 30,000km in diameter, and designed to fire laterally for over hundred thousand light years at maximum strength and the correct tuning, rather than spherically. A Forerunner by the name of Maker-of-Moons quickly saw the flaws in the Greater Halo Array and drew up plans for a more efficient, more powerful, smaller Halo Array. While these newer Halos would be delayed by the Ecumene Council to prevent the Builders from acquiring too much wealth, the Master Builder would eventually use these plans, and construct a Lesser Ark, and from it, Halos 10,000km in diameter that could fire spherically at a radius of 25,000 light years.