GOLDBERG AND MÄKIVIRTA
AUTOMATED IN-SITU EQUALISATION
AES 114TH CONVENTION, AMSTERDAM, THE NETHERLANDS, 2003 MARCH 22-25
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Frequency [Hz]
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Figure 3. Case study 1, original frequency response (centre loudspeaker), (light curve) unsmoothed magnitude
response, (dark curve) the third octave smoothed response
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Frequency, Hz
Level, dB
Figure 4. Case study 1, room response control filter shapes.
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Frequency [Hz]
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Figure 5. Case study 1, equalised magnitude of the frequency response. Third octave smoothing.
4.2. Case Study 2
This is a case study of a compact three-way loud-
speaker
3
placed in a very well damped listening room.
In this case a reasonable improvement is shown to the
in-situ response, however the fundamental acoustic
problems in the room are not solved and can still be
seen in the final response.
3
Genelec S30D [1]
The loudspeaker has an eight-inch bass driver with a
low frequency cut-off of 35 Hz. There is also a 3.5-
inch midrange driver and a ribbon tweeter having the
upper cut-off frequency of 50 kHz. The loudspeaker
was mounted on a stand and placed next to a hard wall
in the front right position of a 5.1 surround sound
system [40]. The measuring distance was 2.95 m.
Room acoustic measurements are shown in Appendix
D (Figures 17-22). The octave and third octave
reverberation times of the room were calculated
according to ISO3382 [41]. The room is extremely
Level, [dB]
Level, [dB]
