- Time-frequency analysis for QC testing
- Full acoustical fingerprint of defects (e.g., Rub&Buzz)
- Detect excitation frequency and spectral content of distortion for root cause analysis
- Easy 3D limit setting
- Ambient noise detection
- Compatible with Time Frequency Analysis (TFA) post-processing module
The Spectrogram 3D Limits is an add-on feature for the Sound Pressure (SPL) Task of the Klippel QC Software. In addition to the standard results of the SPL Task, the 3DL performs a time-frequency analysis of the measured chirp response using an auditory filter bank which is based on human hearing. In contrast to common Short-Time Fourier Transform (STFT) this filter bank delivers a superior time resolution for identifying impulsive distortion (Rub&Buzz).
The resulting spectrograms provide diagnostics of the spectral fingerprint of any abnormal sound and distortion produced by the device under test (DUT). Testing is made easy through three-dimensional limits that are automatically calculated based on approved reference units.
For a chirp signal, both the excitation frequency (time point) as well as the dominant spectral content of any distortion are identified easily in the provided Exceedance plots that indicate where the spectrogram limits are exceeded. Diagnostics is simplified by the provided 2D projection plots based on the Exceedance.
License Dongle (USB)
- QC Standard Software 7.2 or above or
- QC Stand-alone Software or
- SPL Task for R&D application (dB-Lab 212.232 or above)
Other Modules of the QC System
- Sound Pressure Task (SPL)
Chirp-based measurement of frequency response, THD and Rub & Buzz
- Production Noise Immunity (PNI)
Ambient noise detection with auto-repeat and merging
- Time Frequency Analysis (TFA)
Time-frequency analysis and auralization of impulse responses and waveforms based on wavelets, filter-bank or STFT