Portable electronic device protective sleeve with passive sound amplifier

A protective sleeve 10 for a portable electronic device with a hollow sound amplifying member 20 wherein sound is emitted through the audio port of the device and passively amplified through the sound-amplifying member. The amplifying member may form a zig-zag shape with the diameter increasing in the shape of a horn 22. The horn may detachably connect 21 to the cover, which may have a trough 11 for the device to be located or cover the outer surfaces of the device. A hole on the rear of the cover may allow a positioning post to fix the horn in place and prevent pivoting. The amplifying member may be constructed from two detachable parts. In another embodiment the device may be clamped between two rods to attach it to the sound amplifier. The portable electronic device may include a MP3 player, mobile phone or digital camera and the sleeve, which may be made from plastic, rubber, silicon or leather, may communicate with the built-in loudspeaker of the device. The use of an external loudspeaker in unnecessary with the sleeve itself generating a sufficient sound-amplifying effect.