digital amplifiers HA 450,HA550,HA650,HA800,HA900,HA1000 1.Slew rate: ... 2.standard 3-pole connector 3.damping factor>600 digital amplifiers HA 450,HA550,HA650,HA800,HA900,HA1000 feature:HA series ... . Technical advice for speaker box will be offered freely. digital amplifiers HA 450,HA550,HA650,HA800,HA900,HA1000