Carvin Stagemate – I have two of them, both with the available “effects” – they are extremely versatile with a four channel mixer for mikes or lines built in – the battery will last 3 hours on a charge or 1 1/2 if you add the extension speaker – I use separate bass and treble transducers in my harp and blend the sound through two of the channels – I’ve been using mine for over ten years regularly at both indoor and outdoor weddings and events – I have also found them to be very handy when playing in hotels, as I am often placed against a moveable wall in a ballroom where there is no power – also use it regularly at my restaurant job just to cover the area a little better –