Hi, I got this circuit out of a book and it wasn't clear what the OP-AMPs were but will these be right?
Thanks
Boscoe
An externally hosted image should be here but it was not working when we last tested it.
Thanks
Boscoe
Not really.
U2 & U3 - why are you summing the output back in?
U3 & U4 - may lead to instability as you are asking for less than unity gain as frequency rises, also the response will be droopy and to make a 2nd-order active filter there are proper ways that only require one op-amp.
Take a look at the sub-woofer controller project on my website, it is exactly what you need.
U2 & U3 - why are you summing the output back in?
U3 & U4 - may lead to instability as you are asking for less than unity gain as frequency rises, also the response will be droopy and to make a 2nd-order active filter there are proper ways that only require one op-amp.
Take a look at the sub-woofer controller project on my website, it is exactly what you need.
Hi,
A MFB filter will allow both low pass and summing of multiple inputs with just one opamp.
You can use an inverting summing opamp and a Sallen & Key unity gain filter requiring 2 opamps.
You can also use an inverting summing opamp and a Sallen & Key equal component value filter again requiring 2 opamps.
A MFB filter will allow both low pass and summing of multiple inputs with just one opamp.
You can use an inverting summing opamp and a Sallen & Key unity gain filter requiring 2 opamps.
You can also use an inverting summing opamp and a Sallen & Key equal component value filter again requiring 2 opamps.
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