A multiplexer is a device that allows a single channel Real Time Analyzer to average information from up to four microphone positions in a single test. When this information is processed by an analyzer that has "time averaging", the resulting curve is called "spatially averaged". Spatial averaging is recommended by all of the major film cinema/home theater organizations, including LucasFilm, and Dolby Laboratories.

The advantage of multiplexing is that the resulting curve on the real time analyzer reflects the overall response of the room across the entire seating area, rather than only the acoustics of a single point in the room. The multiplexer itself is essentially a small 4x1 mixing board combined with a switching network that automatically samples information from each of the microphones for a specified amount of time.

The MX4 allows the user to enable single channels or any combination of channels, allowing for comparison of individual microphone locations versus the spatially averaged data from multiple microphone tests. Each of the four channels has a gain control to allow the user to match the input level from different locations.

The MX4 can be used with all Gold Line 1/3 octave Real Time Analyzers and with most other popular models. The MX4 can be provided with three or four (Product ID MX4310 or MX4410) Model TEF04 instrument microphones depending on your requirements.