12V Battery powered Subwoofer filter (Tested)
This circuit is useful for someone with DIY car stereo, portable active speaker or for 2.1 single supply audio amplifier... Made in Slovakia
Cut-off frequency is set to 160 hz, which is just fine. If you want to tune it, change R10 Value.
500 Ohm - 318 Hz cutoff
2k -80 Hz cutoff
Use this tool to calculate cutoff:
http://sim.okawa-denshi.jp/en/CRtool.php
I used double OpAmp, because they're easier and cheaper to buy here :)
Contact me, to show where you used it please :)