what adsl2+ splitter is best

high there i recently got adsl2+ connected bought a new netgear n600 adsl2+ modem am currently using standard filter/splitter that came with this modem , am only ranging around 10mbps , i was recently told by using a higher better splitter/filter it can increase to much higher speed , if this is true what is the best one to buy ? if anyone can answer or help me out it would be apreciated , thanks .