TAS3001CPWR datasheet(35/56 Pages) TI

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8−3

Figure 8−3. Typical Small Loudspeaker Response

In addition to equalization of the frequency response, the TAS3001 can be used to notch out specific frequencies that

excite mechanical resonances in the speaker. The removal of mechanical resonances improves the temporal

response of the loudspeaker, so that it more accurately reproduces a recorded signal. For small and ported

loudspeakers, a high-pass filter eliminates signal energy that is lower than the speaker can reproduce. This filtering

improves the loudspeaker power handling and intelligibility by eliminating large cone excursions produced by signals

that are below the loudspeaker resonant frequency.

The kinds of corrections being discussed here begin with a thorough understanding of the inherent operation of the

particular loudspeaker. This information can best be obtained by means of a measurement such as that shown in

Figure 8−3. The measurement information allows the equalization designer to find the resonances and other

problems associated with the speaker and to correct them.

8.3

Sound-Based Speaker Correction

While a high-quality speaker measurement can be extremely valuable to the equalization designer, many good

equalization designers also rely upon their own perception of the sound from the speaker. Based upon what they

measure and hear, designers are able to design filters to achieve a specific frequency response and desired sonic

character. Digital filters can be used to provide these corrections and shape the produced sound.

8.4

Loudspeaker Equalization Example

An example of loudspeaker equalization follows. In Figure 8−3, a loudspeaker has the frequency response shown.

In Figure 8−5 the designer specifies the desired response that is the center of the three new lines. The lines above

and below the center line are the + and − tolerances. The tolerances can be adjusted.

TAS3001CPWR Datasheet(PDF) 35 Page - Texas Instruments