Thank you all for some excellent options. I didn't think the bass would vibrate the house due to the mass of the floor. I'll start with the cheaper options like hockey pucks.
Speakers on carpet over concrete
My system is current located in a partially finished basement. The floor is thick carpet over a thick pad on top of concrete. Does it affect performance of the speaker differently if spikes are used that pierce the carpet and pad, contacting the concrete below versus removing the spikes and having their "feet" resting on top of the carpet which is also a bit less stable? I'm sure I'm not the only one with a system installed on carpet over concrete. How are yours set up?