Certes KLEAR AUDIO KLR1m, User Manual

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I have discovered that Behringer ECM-8000 microphone differs from my
Earthworks just for 0,5 dB in region of 20 kHz and that is why I can easily use them
both without any correction.
In most cases microphone curve errors are negligible in comparison to loudspeakers
ones.
FAQ
What level of measurement signal is optimal?
•
Output signal level should exceed present noise level or at least be equal.
Ordinary the level of human speech is fair enough.
•
Input level (sensitivity of microphone) could be any, but it should not start
clipping (0 dB FS)
•
If the difference between blue (interference) and green (measurement) curves is
less than 10 dB, then there are problems. Try to measure once more with
higher output level and if you see the same picture it means than there are
huge problems with room (resonances) or there is a problem with sound card
drivers. The Impulse Response graph can help in such case.
What is the recommended distance from the virtual measurement plane to
FOH?
The closer is the better. But not closer than distance commensurate to the loudspeaker
systems size. If height of the loudspeaker is 2m then the distance (radius of
measurement segment) should not be closer than 2m. If the system is hung in height
of 4m it means that the distance should not be closer than 4 m.
What should be a size of the plane “painted” by measurement microphone?
The measurement plane (segment) must reach reflective surfaces and must cover as
much as possible all main beam of loudspeaker’s sound field. It can be explained as
“painting” of some imaginary “fence” that is made from “boards”. If the surface is
large (concert hall case) “boards” of the “fence” can be more seldom. I t is important
to collect 12- 15 “boards” and 12 -15 points on every of them and those measurement
points and “boards” should be spread evenly. If you are not sure about equability, you
can perform various measurements and then put them together (merge) in “ Composite
correction”.
Time window
– what depends on it?
Measurement curve accuracy in LF depends on it. If the time window is narrow HF
are processed more accurately but you lose information on LF. If you are going to
work with very low frequencies, then you should increase time window till 100ms or
even 200ms. You should perform similar actions if you are working with problematic