The Resonance Series Auras are crafted out of stainless steel, which, after several rounds of heating, becomes a distinctive earthy orange-brown color. Stainless steel provides the Resonance Series with increased sustain and warm timbre, while also lessening the impact sound when striking notes. The increased sustain makes the Resonance Series instruments perfect for more meditative play, where letting notes ring out is ideal. Stainless steel provides inherent corrosion resistance.