Understanding Sound Level Meters: Basics, Types, and Manufacturers

The meter used to measure sound noise level is known as a sound meter or sound level meter. This article covers the basics and types of sound level meters, and mentions some manufacturers.

Definition: As we know, sound level measurement is very useful in the field of acoustics. The meter used for quantification of different types of noise is known as a sound level meter. It’s widely used in industrial, environmental, and aircraft settings.

It’s important to note that a sound meter doesn’t perceive human loudness level. Just the level of sound isn’t enough; frequency is also equally important. Hence, better response over a wide frequency range is considered more accurate in a sound meter.

Basics and Types of Sound Level Meters

Following are the different types of sound level meters (SLMs):

• Integrating meter and non-integrating meter
• Class-1 and class-2 based on IEC standard
• Type-0, Type-1 and Type-2

Integrating meter: This type is used to measure sound level in Leq (Equivalent Continuous Sound Level). It is often employed in occupational and environmental noise level monitoring.

Non-integrating meter: This meter is used to display instantaneous noise level at one moment in time. It’s suitable for spot-checking and for steady sound level monitoring.

Both class-1 and class-2 SLMs adhere to the IEC standard. Both have the same functions but they have different tolerance errors.

• Class-1: Offers a wider frequency range and tighter tolerance.
• Class-2: Offers a narrower frequency range and lighter tolerance.

There are three types of SLMs as per ANSI standard:

• Type-0: Used in laboratories
• Type-1: Used in precision measurements in the field, and also used in the design of noise controls
• Type-2: Used for general-purpose measurements

Manufacturers of Sound Level Meters

In order to select the right SLM, one needs to decide based on the respective application of use. There are two main categories of SLMs viz. general purpose and special. General-purpose SLMs are used when it is desired to measure noise emitted from various sources such as a water pump. Here, Type-2 with frequency weighting-A option is chosen.

Special applications include occupational, industrial & environmental, community, and research. For these types of applications, SLMs of type-1 or type-2 with A/C frequency weighting along with Leq measurement are used.

Here are some manufacturers of sound level meters: