WILSON AUDIO Subsonic, Installation And Care Manual

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Wilson Audio Subsonic Inst allation Guide
A u t h e n t i c E x c e l l e n c e
better yet, if available, the “Flat”/ non-weighted scale of your
instrument. See the illustration on the following page, which
compares dB-A & dB-C weighting. The more commonly used
dB-A scale, on the other hand, is intended to correspond to the
ear’s “frequency response” at low SPL and should never be used
to calibrate low frequency levels. Please note that, even at 50
Hz, the dB-C scale is still down approximately 2 dB relative to
800 Hz. Don’t be disappointed, therefore, if your dB-C scale
measurements show a gradual roll off in the bass. If your mea-
surements follow the profiled roll off, it indicates a very linear
speaker/room response. Use track 2 (pink noise) for spectrum
analysis measurements. For measurements using a SPL meter,
use tracks 6 through 16, (1/3 octave BLN beginning at 200 Hz
and going down to 20 Hz). Document your measured results.
Warning: Tracks 17 through 27 are sine wave tones at the 1/3-octave center
frequencies. These should not be used to perform in-room frequency re-
sponse estimates due to gross inaccuracies which will be created by stand-
ing waves. Pure tones are included to scan for mechanical resonances and
other distortions.
Notes Regarding the Interpretation of Measurements
• Use “slow” meter response ballistics to help average out the
reading… and to keep from going crazy trying to read it!