A simple L-,pad to drop gain by 26 to 30 dB from speaker output and feed to your subwoofer low level inputs. This has following advantages,
- subwoofer picks the sound signature of your main amp.
- you need to setup the subwoofer level only once. Every time you adjust your main volume the sub volume follows.
- subwoofer picks the sound signature of your main amp.
- you need to setup the subwoofer level only once. Every time you adjust your main volume the sub volume follows.