Here's an example of a reply from Perplexity.ai
I asked, "Why would someone be interested in loudspeaker measurements from the Klippel NFS?"
Response:
"The Klippel Near Field Scanner (NFS) offers several advantages for loudspeaker measurements that can be of interest to audio engineers, researchers, and enthusiasts.
1. **High Accuracy**: The NFS provides highly accurate measurements, even surpassing the accuracy of an anechoic chamber[4]. It uses a moving microphone to scan the sound pressure in the near field of a loudspeaker system, which allows for precise measurements of sound pressure level (SPL) at any point in 3D space and directivity in near/far field[1][2].
2. **Efficiency**: The NFS is fully automated and can measure a loudspeaker in about 2.5 hours, which is significantly faster than traditional methods that can take 10+ hours or even days[4]. This efficiency is further enhanced by the ability of the NFS to measure thousands of points around a speaker in just a few hours[5].
3. **Versatility**: The NFS is applicable to large loudspeakers and can be set up in various size configurations to accommodate different room and Device Under Test (DUT) sizes[1]. It is especially good at examining devices where a single, on-axis measurement does not accurately describe their performance at various listening positions[5].
4. **No Anechoic Chamber Needed**: Traditional far-field measurements of large loudspeakers require large anechoic chambers, which are expensive to build and maintain. The NFS, however, can separate radiated sound from reflected sound of the room, eliminating the need for an anechoic chamber[1][5].
5. **Low Frequency Measurements**: The NFS allows for low frequency measurements without anechoic conditions, which is particularly useful for subwoofer measurements[2].
6. **Distortion Measurements at High SNR**: The NFS can perform distortion measurements at high Signal-to-Noise Ratio (SNR), providing valuable data for audio quality analysis[2].
7. **Holographic Measurement**: The NFS makes a holographic measurement of the sound pressure in the near-field to generate a set of coefficients that accurately determine the sound field[8].
In summary, the Klippel NFS provides a comprehensive, efficient, and accurate method for loudspeaker measurements, making it a valuable tool for anyone interested in audio engineering and research.
Citations:
[1]
https://www.klippel.de/fileadmin/klippel/Bilder/Our_Products/R-D_System/PDF/C8%20Near%20Field%20Scanner%20System.pdf[2]
https://www.klippel.de/know-how/measurements/sound-radiation-and-propagation/near-field-measurement.html[3]
https://www.youtube.com/watch?v=6j-hg_hRUDM[4]
https://www.avsforum.com/threads/i-just-purchased-the-klippel-near-field-scanner-for-my-site-channel-erins-audio-corner.3179815/[5]
https://blog.miscospeakers.com/testing-loudspeakers-anechoic-chamber-vs-near-field-scanner[6]
https://audiosciencereview.com/forum/index.php[7]
https://www.klippel.de/fileadmin/klippel/Files/Brochures/Brochure%20Klippel%20web.pdf[8]
https://audioxpress.com/article/A-New-Approach-to-Loudspeaker-Measurements"