digital amplifiers HA 450,HA550,HA650,HA800,HA900,HA1000 1.Slew ... pole connector 3.damping factor>600 digital amplifiers HA 450,HA550,HA650,HA800,HA900,HA1000 feature:HA series amplifier ... info.Packing:We use foam to protect the speaker box, then put it in cartonOur Service:1. We ... hours.4. Technical advice for speaker box will be offered freely. digital amplifiers HA 450,HA550,HA650,HA800,HA900,HA1000