I am trying to build an equalizer for my circuits class. I just need some pointer in the right direction. Right now I think I am just using lpf, hpf and bpf with "*****" to adjust their cutoff frequencies. Then I will have "*****" to increase the gain on each of these? Does this sound right? If not please point me in the right direction. This is only a basic circuits class so I will be using caps, resistors and opamps to build first order filters, not second-order. Yes, these filters will "suck" compared to real ones but hey, it still gets the job done.

 

Well it's a little more complex then that. What you have described is an active filter that you can adjust the gain of the opamp based on a ****.

This should get you going on the right track
http://www.nuhertz.com/filter/

Their software does a good job at calculating gain and frequency. You can also spec the poles,zeroes and Q, and have it calculate what values to use to achieve that. It still requires you to know what your doing and set realistic expectations.


Modified by nsxxtreme at 3:20 PM 11/13/2008

 

Yea thats a great link, also to note what he said, you can get a boost at certain freq levels, or you can set the boost at crossover points, but i would not do that, what kind of xover slops are you looking to go with? 12db ?

 

This is going to be comprised from single-order ciruits so I don't know if I can get 12 out of it.

 

Why are you restricting yourself to single order filters? With active filters its much easier to find realistic part values.

 

I figured that would be easier. But if it isn't then I can do active filters. I just need to figure out the math as well.

 

Both are "easy" that software even solves the equation for you so you can check your math


*side note*
Honda-tech switched to Vbulletin now huh? Original owners must be gone.