3M DL, SE user manual Setting up criterion curves, Selecting measurement type for curves

92 Criterion curve families

Setting up criterion curves

•Preferred Noise Criterion Curves (PNC) – uses a tangency method but accounts for lower frequencies compared with the NC method.

•Room Criterion Curves (RC) –calculates a numerical rating based on speech interference and indicates any interference such as hissing, rumbling, or vibration. (This method was introduced to determine noise in offices/room acoustics.)

•Balanced Noise Criterion Curves (NCB) –are one of the newer methods that indicate interference from rumble, rattle, and hiss.

•Noise Rating Curves (NR) – used primarily in Europe, Australia, and other country’s room and building acoustic measurements, HVAC studies, machine noise evaluations, and for some community noise enforcement applications.

Setting up criterion curves

Setting up criterion curves is similar to setting up captured curve parameters. However, with criterion curves, you select a specific curve type and then it is applied during your study (or test).

Setting up criterion curves and appropriate measurement type

1.From the start screen, select either 1/1 octave or 1/3 octave for the measurement type. (Repeatedly press first softkey.)

Selecting Measurement type Press first softkey until 1/1 or 1/3 is selected

Figure 6-12: Selecting measurement type for curves

2.Next, select the measurement type, by selecting View Session (use Up/Down Arrow to select) and press Enter . Select the appropriate meter 1 settings (using the softkeys) and set the response time, weighting, and measurement type. (See Figure 3-4, page 27for an example).

Models SE and DL