Design an ACTIVE band-pass filter for the midrange part of a loudspeaker so that the bandpass region is 400 Hz-2000 Hz (as defined by the -3dB points). Design the circuit so that the absolute gain is 2. a. Draw the circuit diagram and specify the resistor and capacitor values. Assume you can use either 100, 330, 500, or 1000 Ohm resistors and can select any value of capacitor. b. Sketch the frequency response (Gain [dB] vs. frequency (Hz)). Note that you will need to convert your gain to dB before plotting. Magnitude (dB) 15 10 5 midrange 12 1 -5 -10 -15 -20 -25 10 100 1,000 Frequency (Hz) 10,000 100,000

Styles 1. The noise produced by a resistor is to be amplified by a noiseless amplifier having a voltage gain of 75 and a bandwidth of 100 kHz. A sensitive meter at the output reads 240 μV rms. Assuming operation at 37° C, calculate the resistance of the resistor. If the bandwidth were cut to 25 kHz, determine the expected output meter reading. (Ctrl) -

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In a Wien bridge oscillator circuit, the value of the resistor andnthe capacitor that form the RC series and parallel branch are given as 200 ohm and 10 mF. What will be the frequency of oscillation?

CR active filters find extensive use in communications and instrumentation measurements. a) By considering how the capacitor impedance in Figure 1 varies with frequency, explain if the circuit in Figure 1 acts as a low-pass or high-pass filter. p) Derive the closed-loop gain for the case of very high frequencies. c) Draw a graph that shows the frequency response of the CR active high-pass filter. The y-axis should correspond to gain in dBs and the x-axis to frequency. Make sure that you clearly indicate the 3 dB point and the equation that describes the relationship between w and CinRin at the cut-off frequency. Cin Rin A Vin Vout Figure 1