Subwooofer with Monoblocks set up question

@kirkwallace  I don't understand why REL is against stacking s/550 or any subwoofer in stereo mode?? The s550 is their poster boy in favor of stacking.

If they want you to stack only in mono... OK, not a problem to set up. However if most low bass is mixed in mono why would it matter??? The concept is the physics involved in the coupling the two speakers together to create one unified signal.

Did they give a reason why? I find it odd.

BTW... I read on their site that they don't want you stacking their other subwoofers because of weight concerns. What??? They're suggesting that stacking a 65 lb. sub may not be able to take the weight?  That's silly. They seem to want you to buy only the expensive ones that are specifically designed to carry the weight. Most subs you can stack a Buick on them no problem but not the REL ?

From REL’s Regional Sales Manager:

”We usually don't recommend stacking stereo subs on top of each other, you will typically get better performance if they are each individually set in a different part of your room, which will help smooth out your bass response and allow each sub to utilize the floor's boundary gain.”

And i think the point about not stacking the subs that they have not specifically designed for stacking is that the ones designed for it come with hardware that allows you to bolt them together, so the upper one(s) can’t be knocked off the lower one(s) by passersby (be they human or otherwise).

"Not all RELs can be stacked due to safety concerns; it takes a lot of weight for a line array to be stable. Therefore, stacking 3 lightweight subwoofers on top of each other is unwise."

REL goes on to explain that only certain models are engineered for stacking and include the necessary hardware to safely create a rigid column.

They specifically state that the T/x series is not approved for REL Line Arrays. In the article "Why You Can't Stack T/x," REL says that their stackable Line Arrays use Serie S and Reference models that were designed from the outset with:

• Metal couplers
• Bolted connections
• Special inserts and rails
• A structure that effectively turns multiple subs into a single heavy tower

If you put shelf liner between them there is NO WAY they can slide off. Especially when only using 2 subs stacked. Perfectly fine. Why discourage it? Only buy the expensive ones is what they're saying.

#chacun a son gout/caveat emptor, I guess?