How to explain something completely ass-backwards. Plots don't 'obtain' equations: equations lead to plots. The concept of upper and lower cutoff frequencies is redundant in low-pass or high-pass filters: there is just a cutoff frequency. There's not much point in talking about cutoff frequencies before stating what w0 means. Cutoff frequencies and band-passes and band-stops and orders appear in all filters, not just Butterworths. Many filters tend to flat cutoff slopes, not just Butterworths, and the graphs drawn with the little curls near zero do not illustrate that correctly. Butterworth filters are not just flat but _maximally_ flat in the passband, and _this_ is what distinguishes them from all others. The gain of an HPF does not decrease with frequency. f0 does not represent the frequency of the signal. The cutoff frequency is not 'about' but _exactly_ the 1/sqrt(2)) point, by definition. _n=1_ defines a 2nd-order Butterworth filter, not s first-order, and there is no such thing as a first-order Butterworth. Similarly _n=2_ defines a fourth order.The rate of change of gain in a Butterworth filter with _n=1_ is not 'about 20 dB/decade' but _exactly_ 40dB/octave, again by definition, and again there is no such thing as a 20dB/decade Butterworth filter.. Filters are not confined to radio frequencies. The ideal for _any_ filter is A=1 in the passband and A=0 in the stop band: not just for Butterworths.Too much waffle and nonsense here, and several major errors.
Very clear and a good introduction to Butterworth Filters !
Awesome Job! summary was on point
Nice sir
I am from India .👍☺️
thanks for the help for my presentation
Thank you so much, this help me a lot
Thanks a lot very clear explanation
How to explain something completely ass-backwards. Plots don't 'obtain' equations: equations lead to plots. The concept of upper and lower cutoff frequencies is redundant in low-pass or high-pass filters: there is just a cutoff frequency. There's not much point in talking about cutoff frequencies before stating what w0 means. Cutoff frequencies and band-passes and band-stops and orders appear in all filters, not just Butterworths. Many filters tend to flat cutoff slopes, not just Butterworths, and the graphs drawn with the little curls near zero do not illustrate that correctly. Butterworth filters are not just flat but _maximally_ flat in the passband, and _this_ is what distinguishes them from all others. The gain of an HPF does not decrease with frequency. f0 does not represent the frequency of the signal. The cutoff frequency is not 'about' but _exactly_ the 1/sqrt(2)) point, by definition. _n=1_ defines a 2nd-order Butterworth filter, not s first-order, and there is no such thing as a first-order Butterworth. Similarly _n=2_ defines a fourth order.The rate of change of gain in a Butterworth filter with _n=1_ is not 'about 20 dB/decade' but _exactly_ 40dB/octave, again by definition, and again there is no such thing as a 20dB/decade Butterworth filter.. Filters are not confined to radio frequencies. The ideal for _any_ filter is A=1 in the passband and A=0 in the stop band: not just for Butterworths.Too much waffle and nonsense here, and several major errors.
very useful...thank you sir
nice jpb man!