Planar subwoofer design is not too complicated as a subwoofer box or bass reflex in general, but in order to get a satisfying sound character, the design must be appropriate and use good materials especially for speaker boxes. Planar itself has 2 types namely long and short type. Materials that are expensive are not necessarily good when talking about speaker boxes; for example plywood which is more expensive than MDF material, the result is not as good as MDF material if it is applied to speaker box. Meanwhile, particles are salon materials that are sold in the market, but particles are not good material and the quality of the results is still below plywood.