LM1036 Datasheet, PDF (8/10 Pages) National Semiconductor (TI) – Dual DC Operated Tone/Volume/Balance Circuit

Applications Information (Continued)
When adjusted for maximum boost in the usual application
circuit, the LM1036 cannot give additional boost from the
loudness control with reducing gain. If it is required, some
additional boost can be obtained by restricting the tone con-
trol range and modifying C_t, C_b, to compensate. A circuit il-
lustrating this for the case of bass boost is shown in Figure
13. The resulting responses are given in Figure 14 showing
the continuing loudness control action possible with bass
boost previously applied.
USE OF THE LM1036 ABOVE AUDIO FREQUENCIES
The LM1036 has a basic response typically 1 dB down at
250 kHz (tone controls flat) and therefore by scaling C_b and
C_t, it is possible to arrange for operation over a wide fre-
quency range for possible use in wide band equalization ap-
plications. As an example Figure 15 shows the responses
obtained centered on 10 kHz with C_b=0.039 µF and
C_t=0.001 µF.
DS005142-16
FIGURE 13. Modified Application Circuit for Additional Bass Boost with Loudness Control
DS005142-17
FIGURE 14. Loudness Compensated Volume
Characteristic
DS005142-18
FIGURE 15. Tone Characteristic (Gain vs Frequency)
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