Audio filter with the TL 071 or the 741 Opamp to make speech better intelligible: schematic/demo

Please read the description/textbox first. An audio filter made with an Opamp (the TL 071 or the standard “741” Opamp) that “pushes up” the audio bandwidth that goes from 2000 Hertz to 4000 Hertz.

Thus pushing down (say) the lower and the higher frequencies in the audio band, that goes from 20 Hertz to (say) 20 KC (or 18 KC).

Correction to the video: Potentiometer 2 (P2) is 50 K (50000 Ohm), so not 1 M. Somewhere in the video I suggest that I have used 3 x a potentiometer of 1M. That is/was thus not true, one of them is 50 K. Even 10 K could work better there (P2, in the schematic).

The video speaks for itself & everything is explained in the video.

Music: "In Albany, New York", from the 127 ers. Copyright music from You Tube.

Feel free to test it and use for the two crucial capacitors (that are for a big part responsible for the audio bandwidth) instead of 10 N (=0.01 uF) other capacitors.

E.g. two 47 N (=0,047 uF) or 100 N (=0,1 uF) caps. Try/test/evaluate/experiment. Or use this circuit directly in practice.

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