LM1036M Datasheet, PDF (8/14 Pages) Texas Instruments – Dual DC Operated Tone/Volume/Balance Circuit

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FIGURE 4. Tone Characteristic (Gain vs Frequency)
Figure 8 and Figure 9 illustrate the loudness characteristics
obtained with C_b changed to C_b/2 and C_b/4 respectively, C_t
being kept at the nominal 0.01 μF. These values naturally
modify the bass tone response as in Figure 2 and Figure 3.
With pins 7 (loudness) and 12 (volume) directly connected,
loudness control starts at typically −8 dB volume, with most
of the control action complete by −30 dB.
Figure 10 and Figure 11 show the effect of resistively offset-
ting the voltage applied to pin 7 towards the control reference
voltage (pin 17). Because the control inputs are high
impedance, this is easily done and high value resistors may
be used for minimal additional loading. It is possible to reduce
the rate of onset of control to extend the active range to
−50 dB volume control and below.
The control on pin 7 may also be divided down towards
ground bringing the control action on earlier. This is illustrated
in Figure 12, With a suitable level shifting network between
pins 12 and 7, the onset of loudness control and its rate of
change may be readily modified.
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FIGURE 5. Tone Characteristic (Gain vs Frequency)
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FIGURE 8. Loudness Compensated Volume
Characteristic
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FIGURE 6. Tone Characteristic (Gain vs Frequency)
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FIGURE 9. Loudness Compensated Volume
Characteristic
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FIGURE 7. Loudness Compensated Volume
Characteristic
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