Hello, I want to make a 2nd order low pass filter to increase the power handling and limit the excursion of a pair of small speakers . Because the space is very limited I would like to use small caps/inductors in the line level side. I would like the filter to cut below 80-75ish hz. Would a capacitor-inductor (3.6 mF, 0.6mH) work? What would the q of such a filter would be ?
An active one would complicate things, and I am space limited. Ideally I would just use a amp with integrated dsp, but i cant find one relatively small.
Something like this ?
You persist with the inductor, ok. As an example say you were prepared to work into 1k. You'll want an inductor like this, maybe 3H
Such an inductor should be wound carefully so that it doesn't have its self resonance within the audio band.
Such an inductor should be wound carefully so that it doesn't have its self resonance within the audio band.
Sorry, I misunderstood your first reply. What, did you have in mind for a non resonant T filter
For example you could use CRCR. Using say R/4R or greater spread you could get a second order LR rolloff.
https://www.t-linespeakers.org/tech/filters/passiveHLxo.html
An LC passive at the impedances seen makes for very difficult to source sizes.
Second order CRCR is quite droopy (may not be an issue given the use), but one needs to have a fairly large input impedance on the amp to make it practical and serious drive and low output impedance from the pre-amp.
dave
An LC passive at the impedances seen makes for very difficult to source sizes.
Second order CRCR is quite droopy (may not be an issue given the use), but one needs to have a fairly large input impedance on the amp to make it practical and serious drive and low output impedance from the pre-amp.
dave