Those were my thoughts also. So, i suppose this is in effect "taking the long way around" to maximize one's profit on a pair of 511A brackets.
It's always been my understanding that the bracket was originally intended to provide true omni-directional positioning when the 511A was used as a stand alone paging/PA speaker.
I guess i have a fetish for the bracket, they could not have been inexpensive to produce, and seem to be fairly uncommon in the marketplace.
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