Certes KLEAR AUDIO KLR1m, User Manual

Page: 20 / 28

“smoothing” to 1 okt., press “ Calculate ”. Now you have edited directivity
curve. 2) go to first (initial) PFR measurement (select it) in measurement tree,
set check box in lowest place in “Compensations, corrections, targets”, brows
for *_PRS.dat file of previous recalculation, press “v” button to see is your
selection right, check the check box “Inv”, press “Calculate”. APL Workshop
software will sum two curves – initial PFR curve and directivity curve. Now
you have curve that represents PFR of loudspeaker with directivity
compensated.
Or you may evaluate that “raw” directivity curve “by eye” and use appropriate
parametric EQ.
Both actions can be combined in pursuit of an ideal result
.
Measurement microphone calibration and verification
For measurement microphone testing there is no need for measurement (anechoic)
camera.
This test may be
done by comparison of 2 or more microphones. You can use any “on
table” loudspeaker, which has wide frequency range, to compare those
microphones and find correction curve for one of them if you know curve of another
one.
Measure loudspeaker with one microphone, then with another one and then compare
curves in any manner you prefer. It is important that measurement “painted” area is as
equal as much as possible for both measurements.
For this reason you can practice with the same microphone by measuring the
loudspeaker for few times to train your hand to get highly repetitive results. You
should make marks on table to perform same “painting” for each measurement.
To find the curve of the microphone under test you must subtract loudspeakers curve
(obtained by the reference microphone - reference curve) from curve obtained by the
microphone under test. This should be done by adding the reference curve as
“correction” in APL Workshop software “Compensations, corrections, targets” for the
measurement obtained by the microphone under test.
Usually, the measurement microphone curves have sloping characteristics. There is no
sharp unevenness on them.
I recommend having available 2 microphones, whose you can compare any time and
one is always in reserve. If you have found a pair which is equal that means that both
of them are accurate.