The Bose Wave Music Systems are reputed to have the fullest sound of any audio component in their class. But if you want to get even more sound out of one, you may be considering adding a powered subwoofer. Unfortunately, the most recent Bose Wave models don't have regular output jacks, only a single headphone jack. That makes adding a subwoofer out of the question with the entry-level Bose Waves, but you can still add a subwoofer to a Bose Wave II. You just need to use the right adaptor cable and make a programming change in the unit's set-up menu.
Plug the 3.5-mm plug on the adaptor cable into the headphone jack on the back of the Bose.
Insert the two RCA plugs (white and red) into the input jacks on the rear of the subwoofer.
Press and hold the "Menu" on the top of the Bose until the words “SETUP MENU” show in the LCD display.
Press the "Play Mode - Options" button until the “HEADPHONES JACK” option shows in the display.
Press the "Menu - Adjust" button to change the option from “HEADPHONES” to “LINE OUTPUT."
Press any buttons except the Menu or Play Mode buttons to exit the set-up menu.
Turn on the subwoofer.
Start playing either the radio or a CD on the Bose. Adjust the Bose and subwoofer volumes to get a pleasing balance.
It's always a good idea to make sure your powered subwoofer and your Bose Wave are plugged into the same circuit. Otherwise, any problems between the two circuits could cause noise on your Bose or possibly damage the circuits. Set your subwoofer volume while the Bose is playing at a comfortable level. After that, you shouldn't have to touch the subwoofer volume, as it will rise and fall with the volume of the Bose.
Make sure the subwoofer is off when you power up the Bose. If the Bose was left at too high a volume, it could start playing loudly enough to damage your subwoofer—or your ears!