These numbers should be ADDED to the readings from the Radio Shack SPL
meter.
Negative numbers will subtract of course.
The first column shows Frequency.
The second column shows the actual theoretical C-weighting
curve
.
The third column uses the C-weighting curve in the bass and My
corrections for My meter in the
treble. I
compared My measurements of my Hivi RT2's
using Pink Noise and 1/3 octave Warbled
Sine Waves to measurements from the LMS system at my friend's speaker
company.
Hence the square baffle to fit their
test
rig. I did get slightly different values for the Pink noise
and
warbled
sine waves so I have printed the corrections for the Warbled Sine Waves
as
I believe they are more accurate (with less overlap) than those for
Pink
Noise. Actually, these corrections aren't too terribly
different
than
the HTF corrections except for more correction in the upper treble
(which
is also hinted at in the correction curves in the meter's booklet).
Also,
I think the HTF corrections in the bass are a little excessive, so I
just
stuck to the normal C-weighting curve values.
The forth column uses the Home Theater Forum's
measured
corrections for Their meter in both the Bass and in
the Treble.
IMPORTANT!!!!!!
Keep in mind that MY corrections apply to MY meter and HTF's correction
applies to THEIR meter, and that the curves in the RS sound level meter
booklet
isn't exact for any meter. But it is a relief to see that my
curves
and HTF's curves don't vary too much. I guess this shows that
at
least
the HTF corrections are more acceptable than the printed curves in the
booklet
if perhaps a bit "optimistic" in the bass corrections.
FREQUENCY
ACTUAL
THEORETICAL C-weighting Curve (dB)
C-weighting
Correction
in the Bass
and
MY
ADJUSTED
RS
Corrections in the Treble
(dB)