A subwoofer is an extra speaker that will extend the bass of your system. Active subwoofers have built-in amplification; passive ones don't so need to be connected to a separate amplifier. In the case of NaimUniti NaimUniti 2 and SuperUniti products you'll find a pair of dedicated subwoofer RCA outputs on the back panel for making a line level connection to a subwoofer. In the case of the UnitiQute you can use one of the preamp outputs.To connect the subwoofer to your NaimUniti/SuperUniti/UnitiQutee from one of the subwoofer outputs on the back to the input on the subwoofer. Use the second output if you wish to connect two subwoofers to your system as a stereo pair. Once you’ve made the connection run a RCA cabl go to the set-up menu on the UnitiQute by pressing the set-up key [spanner symbol] on the remote then selecting Speakers Next select Type; and you will have the choice of Large all or None. option when the UnitiQute preamplifier output is connected to a subwoofer to augment the low frequency performance of full bandwidth speakers. NaimUniti/NaimUniti 2 Once youve made the connection go to the set-up menu on the NaimUniti by pressing the set-up key [spanner symbol] on the remote then selecting Speakers; Next select Type this will specify the required signal routing and high-pass filtering settings Select the Large + Sub option when a subwoofer is connected to the NaimUniti and used to augment the low frequency performance of large (full bandwidth) speakers. Select Small + Sub when a subwoofer is used to provide the low frequency part of a speaker system incorporating small (restricted bandwidth) satellite speakers. When this setting is used a 100Hz high-pass filter is applied to the NaimUniti speaker output signal. If no subwoofer is being used select Large which means the subwoofer output will be switched off. Given that bass frequencies are non-directional in theory you can place the subwoofer anywhere in the room. However its best to experiment a little to get the best results. For the best integration with your room try to find a room 'node'. Place your subwoofer where you usually sit connect it and then walk around your room listening to the low frequencies. You'll hear lifts in bass in several places caused by the interaction of the bass notes and your room's acoustics. These are 'nodes' and your sub should go in one of these locations. Don't repeat don't turn the volume up too much on your subwoofer. It's one of the most common failings we hear in systems. Bass should underpin your sound contribute to it where appropriate but it isn't supposed to dominate the sound completely.ter-spacing: 0px">The best way to set your sub levels is to play a piece of stereo music that you're familiar with: turn the subwoofer's volume level up until you can just hear the bass starting to dominate a little too much and then drop the volume back a tad. This might not be a completely scientific method but it works