I’ve recently found out an amazing company called Schertler and I got the best harp amplification I could hope for! I personally got the A-DYN http://schertler.com/homepage_schertler/adyn-en.html –which picks up the sound from the whole soundboard, the Yellow blender http://schertler.com/homepage_schertler/preamplifiers-yellble-en.html —to adjust and balance everything, but not only!– and then a good amp. (If you play in big venues usually there is a PA system, so you don’t necessarely need an amp, but the great thing is that YOU choose YOUR sound and so it is not messed up by the sound engineering)..