Audience measurement systems having fixed and portable monitoring devices are provided. A seal is mounted on the body and is adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed. The connector secures ground wire by compression to assure reliability and prevent scoring or deforming the conductor. The first panel includes a first polarizer and a first liquid crystal substrate, and the first polarizer is disposed between the backlight module and the first liquid crystal substrate. Alternatively, analogous steps may be applied at high-rate to analyze, synthesize, and cancel the effects of low-rate interference in a multi-rate signal. In an illustrative embodiment, the media processing device is also adapted to rest on a horizontal structure.