one 12in sub or 2 8 inch subs

I suspect 2 is better than one.

I'm using 2 M&K KX10 powered subs (one one each side) with Lipinski L707's and the sub and monitor sound as they are one speaker. I run the subs just to the outside of the monitors. You also have the option of 1,2, or no sub.

very helpful thank you to all who responded !!!!!

In general, I'd always say that two is better than one. And (see below) four may be better than two.

There are many excellent 12" subs out there for which a pair costs less than a single r 528. Both Rythmik (my choice) and SVS (highly regarded by many) offer a pair of 12" subs that will outperform the Rel on the test bench (not necessarily the same as sounding better). In each case, a pair sells for under $1500/pr. IIRC, the SVS is closer to $1100.

Duke, who posted above, owns Audiokinesis, which sells the Swarm bass system with four 8" subs for $2500. That might be one more good option to consider.

Lots of people love Rel, but I question the value proposition. Not trashing the brand - numbers never tell the whole story and personal preference varies - just suggesting that you might wish to explore some alternatives that offer more measured performance for less $.

As always, YMMV.

Marty

neither, choose at least 15 inch. Subwooder need to be closed, no bass port. Rel is in Europe not that popular anymore. Many Rel sub's I tested are sooo slow. Even wenn people would give me extra free money every day by receiving a free Rel I would not want them in my house.