Noise Criterion - NC - level is a standard uesd to describe the relative loudness of a space within a range of frequencies. Noise Criterion - NC - were established in the U.S. to rate indoor noise like noise from air-conditioning equipment and similar. In Europe it is common to use the alternative Noise Rating Curve - NR.

Comparing Noise Criterion (NC, NCB, RNC) to Noise Rating (NR) and dB (A). In Europe it is common to use Noise Rating Curves - NR. dB (A) - LA - is a weighted method compensating for the human hearing of sound pressure at different frequencies. Choosing appropriate noise criteria is important when specifying acceptable levels of noise.

Calculate Noise Criterion (NC) from octave band pressure levels. The calculator below can used to calculate the NC - Noise Criterion : Sound Pressure Level (dB) - Octave band mid-frequency (Hz)

NC曲线由Beranek发表于1957年，是一系列近似等响曲线的曲线，它们从一系列的SIL（语音干扰等级）值发展而来，这些值在对办公环境的调查中被证明是可接受的。

2023年7月17日 · When designing a soundproof room, acoustic designers will use Noise Criterion Curves or NC curves for short to ensure the room meets proper sound isolation guidelines. In this article I will go over what NC curves are and how to use them as a guide for your own studio build.

The lowest curve which is not touched by the measured spectrum at any position in the audio frequency range is NC-45. The room represented by the black curve has an NC45 rating. A list of Noise Criterion Curves for different types of rooms that should not be exceeded

2023年2月9日 · Noise Criterion [NC] Noise Criterion was developed in the 1950s and was most often used in the United States to depict the acceptable range of background noise in a space. It is measured in the range of 63 Hz to 8000 Hz (8 kHz). …

Noise criteria (NC) curves can be used to evaluate existing situations by measuring sound levels at the loudest locations in rooms (preferably at user ear height). They can also be used to specify the steady, or continuous background noise levels

Noise Criterion (NC) is a single-number rating system used to evaluate background noise levels in indoor spaces. It considers the sound pressure levels across different octave bands and compares them to a set of predefined NC curves.

Many finished engineers spaces rely on the NC tables in manufacturers' catalogs to give them an estimate of noise levels in their proposed contractor as well as a comparison between manufacturers.