The sound level is undetermined.

January 15, 2026

1/15/26

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Nyquist Team

Noise is rarely uniform like the sound of a fan. In urban environments or on production floors, we often encounter sounds that rapidly change in intensity. How do acousticians classify noise that "jumps" on measurement graphs?

Professional Definition

The level of unsteady sound is the sound level at a specific location, observed using a sound level meter with the A-weighting and S (Slow) time weighting enabled, which shows variability during observation greater than 5 dB.

The key parameter here is the amplitude of changes exceeding 5 dB at a time constant of S (1 second). If the fluctuations are smaller, the sound is considered steady. In the case of unsteady sounds, assessing noise exposure often requires determining the equivalent sound level (LAeq), which averages the acoustic energy over time.

Acoustics in Simple Words

Think of driving a car in the city during rush hour. One moment you are stuck in traffic, then you move, then you brake, someone honks, an ambulance passes by with sirens. The speed of your car keeps changing – this is analogous to unsteady sound. The meter needle (or the numbers on the display) does not stay in one place, but continually

Nyquist Team

The Nyquist team is a group of enthusiasts in acoustics, design, and technology who combine engineering knowledge with aesthetic sensitivity every day. We create solutions that improve acoustic comfort and give spaces a unique character. On the blog, we share our experiences, knowledge, and inspirations drawn from our daily work on projects carried out across Poland and abroad. We believe that good acoustics is not just a technique – it’s a way of creating spaces where one simply enjoys being.

Nyquist Team

The Nyquist team is a group of enthusiasts in acoustics, design, and technology who combine engineering knowledge with aesthetic sensitivity every day. We create solutions that improve acoustic comfort and give spaces a unique character. On the blog, we share our experiences, knowledge, and inspirations drawn from our daily work on projects carried out across Poland and abroad. We believe that good acoustics is not just a technique – it’s a way of creating spaces where one simply enjoys being.

Nyquist Team

The Nyquist team is a group of enthusiasts in acoustics, design, and technology who combine engineering knowledge with aesthetic sensitivity every day. We create solutions that improve acoustic comfort and give spaces a unique character. On the blog, we share our experiences, knowledge, and inspirations drawn from our daily work on projects carried out across Poland and abroad. We believe that good acoustics is not just a technique – it’s a way of creating spaces where one simply enjoys being.

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