... eliminatehum, Power LEDs, Channel 1 & 2 level, LED's indicator, stereo and bridge modes, clip indicator. It has reliable protectivedevice for short circuit ... cut at 40 Hz to provent Low-end rumble.2) Frequency Response: 20Hz-20K Hz3) Rising Speed: 45V/Us(BTL-MONO ... .12) Power LEDs, Channel 1 & 2 level, LED's indicator, stereo and bridge modes, clip indicator.13) Dual DC fan to prevent overheating ...