Summarizing we can say that sound insulation is lower than
30 dB below 315 Hz, 250 Hz and 125 Hz respectively of these three
type units (WOG2, WOLG1 and WLG2); sound insulation is higher
than 45 dB above 4000 Hz, 2500 Hz and 1600 Hz respectively for
these three type glass units (WOG2, WOLG1 and WLG2)