Embodiments are directed to a sealed pipe-loaded loudspeaker for augmenting low frequency response in a portable electronic device. A loudspeaker transducer is configured to radiate sound directly out of a forward radiation area and incidentally out of a rearward radiation area, and a sealed transmission line forming a closed pipe acoustically coupled to the transducer through which the rearward radiation propagates to produce standing waves corresponding to the dimensions of the closed pipe, wherein resonances apply a loading to a diaphragm element of the transducer to lower its resonance frequency. An acoustical wave front radiates away from the diaphragm element for the direct sound and is emitted outside of the device, and the rearward radiation is not emitted from the device.