The Simpson 884-2 Sound Level Meter (hereafter referred to as the 884-2 or the Instrument) is a portable, general purpose sound level instrument, capable of accurate sound level measurements over a range of 40 to 140 dB. This encompasses the noise level of a quiet residence to that beyond the threshold of pain. This dB range is compatible with current Federal, State, and local noise ordinance requirements; including safety and environmental noise checks.

The 884-2 meets the requirements of the American National Standards Institute (ANSI) Standard Specification S1.4 - 1983 for "Type S2A General Purpose Sound Level Meters and the International Electro- Technical Commission (IEC) 651." It can be used by industry to measure noise levels to comply with Occupational Safety and Health Act of 1970 (OSHA) and the Walsh-Healy Act, except for direct measurement of impact (impulse) noise.

The 884-2 can be hand-held for rapid testing or mounted on a tripod for measurements over extended periods of time. The meter case is constructed of high- impact molded plastic, especially contoured at the microphone end to minimize reflections of the sound energy field being measured.

The 884-2 is equipped with a range selector switch which references the 0 dB point of the indicating instrument to the range selected. For example, when the range switch is set to 70, the zero (0) mark on the black arc is equal to 70 dB. Fast or slow meter response is switch selectable.

The 884-2 offers three outputs which are proportional to the sound level input: a RMS output, a dB output, and an external filter output that is compatible with the Simpson 898 Octave Band Filter.