Low pass , high pass circuit design

[electronic_satya]

Hi all,

For the understanding of the low pass and high pass circuit using operational amplifier, i want to design the following circuit. Could someone please let me know will it work properly? My requirement is i will try to speak from the mic and would like to hear from speaker 1 and speaker 2 and I expect that some words will be distorted (what exactly will happen can someone please explain?). Am I correct in the design? One more clarification is do we need to give any power to mic or it is present internally?

Thanks in advance,
Regards

 

[Ow@i$]

a typical adult male will have a fundamental frequency of speaking from 85 to 180 Hz, and that of a typical adult female from 165 to 255 Hz, now what i am trying to say is that you need to design very fine filters to separate your high frequency threshold and low frequency threshold as bandwidth is very small....
moreover u will need audio amplifiers to able to hear what you say

 

[udhay_cit]

Satya,
It all are depends to the mic quality & pre-amp design. While selecting a microphone you need to consider good frequency response, impedance of the mic(low imp is good), directional property, sensitivity, etc...., If you select an audio opamp like TI OPA series & if the pre amp section is properly designed(to respond all frequency), then you can get very good output.
We have some dedicated mic preamp like MAX4063, MAX9814, etc...,

Look this....
https://www.microsyl.com/index.php/2010/03/29/very-high-gain-microphone/
**broken link removed**

We need to provide bias current for microphone to operate. Its a simple pullup resistor but the value will vary with impedance of the mic or bias current, etc...,

- - - Updated - - -

Satya,
It all are depends to the mic quality & pre-amp design. While selecting a microphone you need to consider good frequency response, impedance of the mic(low imp is good), directional property, sensitivity, etc...., If you select an audio opamp like TI OPA series & if the pre amp section is properly designed(to respond all frequency), then you can get very good output.
We have some dedicated mic preamp like MAX4063, MAX9814, etc...,

Look this....
http://www.microsyl.com/index.php/2010/03/29/very-high-gain-microphone/
http://sound.westhost.com/project66.htm

We need to provide bias current for microphone to operate. Its a simple pullup resistor but the value will vary with impedance of the mic or bias current, etc...,

 

[electronic_satya]

moreover u will need audio amplifiers to able to hear what you say

Thank you all for quick replies. I just wanted to understand one thing, is the operational amplifier not like audio amplifier in the sense that i can obtain a gain with operational amplifier as well. Could you please calrify this?

thanks in advance,
regards

 

[Ow@i$]

it all depends on configuration in which you are using....
as active filter it won't... as in case like differentiator or integrator... have a look.. it will help you in designing filter..

https://www.vyssotski.ch/BasicsOfInstrumentation/FilterDesignIn30Seconds.pdf

 

[udhay_cit]

is the operational amplifier not like audio amplifier in the sense that i can obtain a gain with operational amplifier as well

Audio amplifiers are specifically designed to drive low impedance load like 4ohms, 8ohms, etc...., Truly audio amplifier is also an OPAMP but specifically for audio. You can not expect to drive 4ohms load using OPAMP...

Regards
Udhay