For the tightest bass, drive self drilling screws directly into the sub-floor (through the carpet), and rest your speaker spikes on the screw heads. You will need to pick screws with a wide nut type head, otherwise it is "very" difficult to line up the spikes with the screws (I did it once on philips heads, but it took some work, now I have a hex type head screw which makes it a little easier). When you move speakers that have been sitting on carpeting, you will see the marks left by the spikes (on most carpets anyway...)which makes it easy to position the screws.
Level the screws (rest a flat ruller on the screw heads between front screws and level, repeat for rear screws, check rear to front). Place speaker and adjust spikes for correct level (I like mine slightly tipped up in the front).
It seems like a lot of work and you must not care for the sub-floor under the carpet but man, you will end up with the tightest, most tunefull bass your speakers are capable of. This also helps with imaging as the speaker is better anchored. It is a big improvement in my experience. Just make sure you have settled on the final location for your speakers before you do this...
"Disclamer: not liable for any damage to floor or fights with significant other as a result of this tweak!"
Cheers.
Level the screws (rest a flat ruller on the screw heads between front screws and level, repeat for rear screws, check rear to front). Place speaker and adjust spikes for correct level (I like mine slightly tipped up in the front).
It seems like a lot of work and you must not care for the sub-floor under the carpet but man, you will end up with the tightest, most tunefull bass your speakers are capable of. This also helps with imaging as the speaker is better anchored. It is a big improvement in my experience. Just make sure you have settled on the final location for your speakers before you do this...
"Disclamer: not liable for any damage to floor or fights with significant other as a result of this tweak!"
Cheers.