Steganography was designed to get users harder to find out the data through hiding data in forms of various materials such as text, image, video, and audio. The most generalized Audio Steganography technique is Lowbit Encoding which insert one bit of message to the last bit. Attacker has the disadvantage where attack was able to do the message which was easily concealed in case of Lowbit Encoding. Also capacity of stego-data is low. To improve low capacity, we embed more than one bit in every sixteen bit. But the attacker easily filters message when inserted bit is equally bits in every sixteen bits, it is proposed that the message should be inserted in forms of sign curve with changing the number of bits.