A muffler for a feed air system of a compressor assembly. The muffler can be a product of a blow molding process and used in a method of sound control for a compressor assembly. A method of controlling sound in a compressor assembly can have the step of providing a feed air and the step of providing the muffler an outlet in communication with an inlet of a pump assembly which can compress the feed air fed through the muffler and into the pump assembly. Sound control for a compressor assembly is also accomplished by adapting a feed air system to have sound control of a feed air path by dampening the sound emitted from a pump system through the feed air path.