How to design active filtersIf you need a special active filter, e.g. for building active loudspeakers or medical electronic equipment, there are many ways you can go for designing this filter. You can use a book like Lancasters Filter Cookbook, "The Art of Electronics" by Horowitz and Hill or the books by Tietze-Schenk or von Wangenheim. You can also use a filter design software. We have read many books and have tested lots of programs. Finally we have arrived at the active filter software AktivFilter. This software is easy to use and does a good job when you need an active filter with opamps. They offer a demo edition of this program which can be downloaded from their website for free of charge (freeware). The demo edition of course has some limitations but we have found that it is a very useful tool. Here is a sample: |