CFO (Chief Fun Officer)
- Feb 13, 2016
- Seattle Area
Only a handful of people own/understand its operation. So if you heard that, it is an uniformed opinionI also saw some comments from other people.
Just as I said above.
- NFS is the most inaccurate among common electroacoustic testers.
Not at all. There is no cover for the microphone. There is a mount for the microphone that is about 2 inches or so. This can cause very slight error when its dimension matches that wavelength. I removed mine and put padding on boom fixture shortly after I got the system. This completely solved the small reflections.
- It has a protective cover for that microphone, the high frequency is easy to be wrong, take off the protective cover, if the setting is wrong, the results will be wacky.
Note that the above has nothing to do with NFS itself as the same issue would exist with standard measurements.
Nope. As explained by NTK, me and Klippel documentation, the system is far superior to anechoic chambers used for audio. The low frequency response is absolutely superior and its resolution is one degree which is far, far better even fine grained anechoic measurements. Even companies like Harman that have more than one anechoic chamber, also own Klippel NFS.
- NFS is a cost down thing, the anechoic chamber is too expensive.
The advantage of anechoic room is speed. There is no computational phase. What you measure is what you get. And if you build a microphone array and use a turntable, you can get your 10 degree measurements much faster. It can also be extremely quiet (if built that way) allowing measurements of THD+N that would go very low.
Gated response gives you perfect anechoic above 1 kHz or so. The reflection is completely removed by the time slice. The problem with it is that you lose low frequency resolution which Klippel solves with field separation.
- I remember that the high frequency of NFS is filtered by the time window, which is different from the anechoic chamber in principle. Mainly low frequency and SNR of the algorithm.
This is complete nonsense. NFS doesn't even come with a microphone. You can buy/use any you want. Klippel does resell some other microphones from GRAS and Microtech Geffell. I own the latter which is an incredible microphone with very low distortion. But again, you can use any microphone and enter its calibration into the system.
- The microphone for NFS is relatively low-end GRAS.
My NFS measurements have been compared to anechoic measurements by both Genelec and Neumann and they are extremely well correlated. The slight difference between mine them has no answer: that is, whether they are wrong or I am. It is very small and only in bass where room impacts anyway.
Here is my measurements of Neumann KH80DSP:
And here is company's anechoic chamber measurements:
It doesn't get any better than this. Or better proof of your FUD in this regard.