Carpet & underlay

Getting new underlay and carpet for the gaming/audio room, and wondering about the underlay. My speakers and subwoofer rest on marble cutting boards. TV is on a free standing stand (50" plasma)


I have purchased two 30M rolls of "Tredaire Dreamwalk 11mm" And concerned would it be too thick, would it cause the speakers, sub and stand to be a bit wobbly?

http://www.tradepriced.co.uk/tredaire_dreamwalk_11mm_carpet_underlay.html


Also planning on getting stairs, bedroom and lounge re-carpetted is this ok to be used for stairs and lounge?


Would it be better to use this in the gaming/audio room?

http://www.tradepriced.co.uk/tredaire_superior_carpet_underlay.html


Gaming/audio room is over a garage, chipboard floorboards. Considering a short pile overall thickness 7-10mm twist carpet.


But then with thicker underlay getting a warmer room in winter (garage is stone cold) and better sound noise reduction