Variable Low pass for sub

[ThSpeakerDude88]

hey I need to know how to make a variable lowpass filter for a cheap portable sub I'm making. Its only 22watts, so nothing hi-fi or fancy. I just need an opamp circuit that is simple, runs off of single supply ( 12v preferably)

I need a cut off frequency of 200hz, variable down to 50hz.

know of any good circuits? I'm new to designing low pass filters..

 

[Nuuk]

There are any number of cheap adjustable active crossovers sold for use in cars , ie 12 volt operation. Have a Google.

 

[GPE]

Low pass filter sch

I wish this attached sch will be useful for you.

 

[ThSpeakerDude88]

well I tried googling it, couldnt come up with much


I need it to run on 12v... not +/- 12v. I have a whole bunch of TLO72's so thats what i'll use.


All I need it to do is mix the left/right channels and have a boost/cut for only the bass frequencies, and I need 150hz up cut off.