In some embodiments, an oxygen concentrator may include lightweight injection molded housing components coupled to dual-pump diaphragm compressors. The oxygen concentrator may be coupled to a pressure transducer that detects a users inhalation. The detected inhalation may signal the release of a bolus of oxygen. The sensitivity of the pressure transducer readings may be adjusted based on a detected environment. The users breathing rate may also be determined to control the number of compressors used for increased efficiency. An ultrasonic sensor and gas flow rate meter may be used to determine an amount of oxygen being delivered to the user. Other components such as step valves and a solar panel may also be used to further conserve battery power. The oxygen concentrator may also incorporate an audio device such as a mobile phone.