respice finem
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Now they probably matter
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PS Audio got a Klippel NFS
- Thread starter Randolf
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respice finem
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Here's a list, looks incomplete though:
I don't think many of those listed own a NFS. Klippel has many more products in its range,Here's a list, looks incomplete though:
EdW
Senior Member
I had gathered that. Not sure what the lower cutoff frequency is though. To accommodate 20Hz the 1/4 wavelength absorbent wedges would be approx. 14 feet. On all sides and top and bottom of the test space. So the overall chamber would be the size of a decent concert hall. KEF perhaps uses open air measurement for very low frequencies? Whatever the case not many other loudspeaker manufacturers do as good a job.
a4eaudio
Addicted to Fun and Learning
They likely use calibration below 80 Hz as Harman does with their anechoic chamber.
a4eaudio
Addicted to Fun and Learning
Yes. Based on this article, KEF was doing something similar back in 1994.
Note that calibration is a Band-Aid. It only works if the same configuration speaker is used together with the same distance from the mic of all low frequency elements. Tower speakers with complex ports, drivers, etc. all create situations where the calibration is wrong.
In early days, Klippel had problems with this region due to another reason: it assumed that the response at very low frequencies was omni and hence, only needed low order expansion. Again, complex port/drivers meant that there is some deviation from this. So a manual undocumented process was created to deal with this which we use. With this change, we are able to measure down to 20 Hz with high accuracy that you can't do with anechoic chamber.
In early days, Klippel had problems with this region due to another reason: it assumed that the response at very low frequencies was omni and hence, only needed low order expansion. Again, complex port/drivers meant that there is some deviation from this. So a manual undocumented process was created to deal with this which we use. With this change, we are able to measure down to 20 Hz with high accuracy that you can't do with anechoic chamber.
I learned a new word today.
kemmler3D
Master Contributor
My impression is that Paul kinda does his subjectivist YouTube thing but @Chris Brunhaver wants to go in a more objective performance kind of direction. Seems like they make it work. If you think about it from a pure business perspective with no investment in philosophy of audio, Klippel measurements are just another market trend to take advantage of, and one that is apparently picking up steam. Paul can't be too bad of a businessman, so it's possible they reach agreement on that ground.
WOW, I remember when the Klippel measurement system was a fairly rare piece of gear. !Here's a list, looks incomplete though:
"You've come a long way baby" since I bought his PS III phono amp back around 1981 on the basis of Peter Aczels review in the "1979 V2-#2 Audio Critic". Cost me the staggering sum of $222 plus tax! Sounded Good To Me, 47 years ago.
LumiAudioNut
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It appears that KEF utilizes a kind of rotating microphone array with the speaker being tested sitting at the center of the rotational axis, with the entire measurement process taking place inside of an anechoic chamber. Judging by the comments from the a manufacturing representative, this apparatus costs quite a bit more than the Klippel NFS.
BTW, keep in mind that Klippel is the name of a company and not a the measurement technique. Klippel’s NFS isn’t the only way to measure a speaker and not necessarily the best. “There’s more ways than one to skin a cat” as it were…
Here is link to the white paper for the KEF LS60 (a link to the PDF file)
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Tom C
Major Contributor
It is my understanding, from my very casual readings, that a Strad has never won a blind test. There may be other reasons to want one, but it does not sound better. So, I guess a lot like a luxury speaker.It is 1716, and Antonio Stradivari’s violin is rejected because it did not measure well enough.
This is not a list of companies that have bought the Klippel NFS, but anything Klippel makes.
That's correct. I think when I bought it, they had sold something like 10 to 15.
The name "Klippel" though, has become mainstream. And I like to take credit for that. That was a name that was known in speaker design and testing, but not by hobbyists and audiophiles.
That was a name that was known in speaker design and testing, but not by hobbyists and audiophiles.- Thread Starter
- #39
As already pointed out KEF uses a motorized microphone array (developed by KEF) in an anechoic chamber. The older interview of Jack Oclee-Brown from KEF by John Atkinson (Stereophile) from 2017 also provides some interesting measurement technique details (15ms quasi anechoic measurements, ground plane outdoor measurements) and is really fun to watch in general:
Sokel
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Judging by the cat, Ayre gear up there must truly operate at class A
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