Spectrum Filter Offset and Current

It was found than when a pull-down resistor is connect to pin 5 (signal input pin) of the LM3915 IC, the port would output ~0.14uA = 140nA, therefore limiting the value of the resistor to 1kohm so that a voltage of no higher than 0.14mV DC would develop
Therefore, for the high-pass RC filter to be appended to spectrum filters, R = 1 kohm
- Sub-Bass and Bass: C = 100uF
- Low-Mid and Mid: C = 10uF
- Upper-Mid, Presence and Brilliance: C = 1uF
The capacitors I have at home that have a capacitance of greater than or equal to 10uF are polarized, but ceramic capacitors exists for up to 100uF, maybe even higher, but they get more expensive
- 1u: $0.11 to $0.138
- 10u: $0.138 to $0.152
- 100u: $0.607 to $0.713
Calculated max current each filter and internal stage will output when amplitude of input voltage signal is 5V (output at final stage will be saturated to 3.5V):
Say signal was completely in the Brilliance spectrum, max outputted current would be 5.345mA. The 3.6mA output of stage 3 is completely due to the 1k ohm resistor of the high-pass RC filter. Assuming each op amp IC which contains 4 op-amps requires 1.5 mA, which there are 6 of -> 6*1.5 = 9 mA
- 9mA + 5.345mA= 14.345 mA. Negative Voltage multiplier can output a current of 17mA and still stay below 8V, so we are in the clear

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