Acoustic kev co tshuab kom huv: Kev txhuam hniav Sonic ib puag ncig ntawm 31000 strokes / feeb yuav pab kom tshem tawm ntau tshaj li 150% cov quav hniav ntau dua li cov ntaub ntawv txhuam hniav kom zoo nkauj, thiab, tus txhuam hniav sonic tuaj yeem pab tiv thaiv kom tsis txhob muaj pos hniav.