Notch filter

[qguy]

newbie warning...

I made notch filter for the woofer with 22 uF capacitor, 1 mH inductor and 15 ohm resistor. This tames the 1000 hz peak of my 2 ways

What would the effect if I reduce / increase the resistor value ?

Reduce / increase the capacitor values ?

I would appreciate responses such as "the mids would be increased" or the notch would move from 1000 hz to 800 hz"

[dieringe]

You know how a notch filter works?

The inductor "shorts" low freqs, the capacitor shorts the high freq. as they are in series, only the range between the two "cutoff-frequencies" is shorted. the resistor determines how strong the shortage is. larger resistor, less shortage, more mids (flatter dip).

larger capacitor, lower frequency. larger inductor, lower frequency.
to experiment you should take a response graph with each modification.

[sreten]

Hi,

Use something like Tina-Ti (free) to answer your own question.

http://focus.ti.com/docs/toolsw/fold...t/tina-ti.html

/sreten.

(to get passive circuits to work just add an unconnected op-amp)

[qguy]

Now I do !!!

This is very much appreciated, I think this is the best response that I got ever from the internet...

Originally posted by dieringe
You know how a notch filter works?

The inductor "shorts" low freqs, the capacitor shorts the high freq. as they are in series, only the range between the two "cutoff-frequencies" is shorted. the resistor determines how strong the shortage is. larger resistor, less shortage, more mids (flatter dip).

larger capacitor, lower frequency. larger inductor, lower frequency.
to experiment you should take a response graph with each modification.