300HZ - 3KHZ Audio Filter

The human speech apprehend a small area of frequencies, that is extended from 300HZ until 3KHZ. This spectrum is also internationally recognized for the transmission of speech via telecommunications networks. This is also the mainer use of this circuit, one and it can be used in uses that we needed this concrete spectrum of frequencies, rejecting the spectrum on and under what, making comprehensible the speech. The circuit is constituted by two active units, filters of second class (calculated for critical damping). The first filter round the IC1A rejects the low frequencies (under 300 HZ) [high pass] and the second IC1B high (above 3KHZ) [low pass], composing thus a total filter band pass of area (300HZ-3kHZ). In order to has good yield the filter, as with all the filters, it should are used resistances metal film 1% and capacitors polysteryne.
300HZ - 3KHZ Audio Filter - schematic

Part List R1= 120Kohm R7= 150Kohm C6= 100nF 100V polystyrene R2= 100Kohm R8= 47Kohm C7= 560pF R3= 470Kohm C1-2-8= 2.2nF 100V polystyrene C11= 150pF R4-7= 8.2Kohm C3= 150pF C12= 10uF 25V R5= 6.8Kohm C4-9= 100nF 100V IC1= TL072 R6= 33Kohm C5-10= 47uF 25V All resistors is 1/4W 1-2%

Leave Comment

characters left:

New Circuits