Both pure copper and copper clad with aluminum can both be used as conductor for wire when there’ s different needs of tone quality. Study shows that higher purity of copper is beneficial to improve sound quality. It can be seen that pure 4N (99.99%) copper is usually adopted in the market. Copper coated aluminum conductor self-adhesive wire conforms to requirement of improving utilization rate of wire without affecting sound quality (high-frequency voice coil). Bond coat of the wire can be activated by two methods of hot air and solvent. This wire is preferred by most customers due to its convenient process to shape and low cost. Diameter of this wire is relatively thin.