Sound is everywhere in our daily life: birdsong, street noise, engine roar, even the faint airflow from an air conditioner. For people, sound is not only about whether we can hear it, but whether it feels comfortable, is disturbing, or poses a risk. The same 70 dB can feel completely different; and when something feels […]

In audio and vibration testing, FFT analysis (Fast Fourier Transform) is one of the tools almost every engineer uses sooner or later: A lot of practical questions are actually asking the same few things: FFT is the most universal entry point to answer these questions. This article will help you clarify three things from an […]

Octave-band analysis can be implemented in two fundamentally different ways: FFT binning (integrating PSD/FFT bins into 1/1- and 1/3-octave bands) and a true octave filter bank (standards-oriented bandpass filters + RMS/Leq averaging). In this post, we compare how the two methods work, where their results match, where they diverge (scaling, window ENBW, band-edge weighting, latency, […]

Octave-band analysis converts detailed spectra into standardized 1/1- and 1/3-octave bands using constant-percentage bandwidth on a logarithmic frequency axis. In this post, we explain the mathematical basis of CPB, why IEC 61260-1 and ANSI S1.11 define octave bands the way they do, and how band levels are computed in practice (FFT binning vs. filter-bank RMS). […]

From the outside, a measurement microphone looks deceptively simple. But in real-world engineering, its interface options are surprisingly diverse: Lemo, BNC, Microdot, 10-32 UNF, M5, SMB... Many newcomers to acoustics ask questions like: This article provides a structured overview of common measurement microphone interfaces, looking at physical connectors, powering methods, cable characteristics, and typical application-driven […]