Today, lectures and presentations are mostly held with audio and visual media support. Connecting laptop computers to the mixing consoles of PA systems, however, can be a major problem due to incompatible connector formats. The Palmer Line Level Convertor PLI06 is a dedicated interface to feed the unbalanced stereo signal typically provided by a laptop to the balanced  (mono) microphone inputs of professional mixing desks. It mixes the stereo output to mono while impedance matching and signal balancing are achieved by a high quality audio transformer especially designed for the unit. Moreover, it also prevents ground loops and the annoying hum they result in. The PLI06 is entirely passive and does not require mains power or batteries.

Connecting the PLI06

Equipment providing audio output on RCA phono sockets is connected to the PLI06's inputs using a shielded RCA stereo cable. For best results with laptops we recommend using their headphones output which is usually on a 3.5 mm miniature stereo socket. Use a shielded TRS mini jack to 2x RCA phono cable for connection to the PLI06. Place the unit close to the signal source and keep the input cable as short as possible since the unbalanced signal path is susceptible to interference. The PLI06's output is on a standard wiring male XLR connector. Use a high quality microphone cable for connection to the mixing console. Due to the balanced lo-Z signal provided by the Palmer Line Level Converter cable lengths are uncritical while interference-free signal integrity is maintained.