Wow - Someone put a lid on this open can of worms...=)
Thank you for all your input - I will give a few ideas a try: Im thinking try the Spikes to the concrete and see if that works. At 50# each I just did not think the spikes would "penetrate" into the concrete and perform properly. The idea of the spikes is to hold the speaker stationary. I was afraid they would "slide/vibrate" around. I will update on how much a PITA it is or was not...and my conclusions
Thank you for all your input - I will give a few ideas a try: Im thinking try the Spikes to the concrete and see if that works. At 50# each I just did not think the spikes would "penetrate" into the concrete and perform properly. The idea of the spikes is to hold the speaker stationary. I was afraid they would "slide/vibrate" around. I will update on how much a PITA it is or was not...and my conclusions