Originally Posted by SteelString
Is there any reason I can't use, say, three Polk RM7 Center speakers for my front LCR speakers? I am physically limited to having to use horizontal mounted left and right fronts, so I thought it would make sense to just buy 3 center speakers since they're made to be horizontal. Would this work reasonably well or is there a reason center speakers can't be used for left and rights, too, as long as they're horizontal?
Well, actually most center speakers are not made to be horizontal, they are simply made horizontal. They still have the lobbing problems associated with the horizontal array. There is a way to make a crossover to make horizontal arrays possible without lobbing but it is very complex and not currently available in any commercial product.
Also, some center speakers like the Aperion 5C and 6C or any other with a similar driver arrangement can work fairly well horizontal because the crossover to the horizontally located woofers can be low enough that lobbing is not a problem.
If mounting them horizontally like this is your only option then it seems like you have no choice. It may not be optimum but it will work.