XW-300d Subwoofer


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  • Perfectly anchors a home theater or two-channel system
  • DCS Technology caters to specific bass preferences
  • Front-firing 8-inch driver delivers hard-hitting intensity
  • 300-watt BASH® amplifier
  • Sealed enclosure



  • The back of the subwoofer is warm. Is this normal?

    A subwoofer will run warm when in use, by design. However, it should not be uncomfortable to leave your hand on the back panel for 5 seconds.

  • I'm not getting any sound out of the subwoofer. What should I check?

    Unplug the system to allow the subwoofer to “reset.” Also, test the speaker using another device. You can plug one end of an audio cable (you may need a RCA female to Mini-plug male adaptor) into the headphone output jack of devices such as a portable CD player or MP3 player; plug the other into either ‘line in’ RCA jacks on the sub to determine if the problem is with the subwoofer or the soundcard drivers. If problems persist, please fill out an online ticketwith our technical support team. 

    Subwoofer Direct CD Test: 

    If you get little or no sound from your subwoofer, perform a "direct in" test to determine if the problem is more than a simple cable or level-setting issue. Start by using a different set of RCA connector cables, then connect the analog audio out from a CD player or DVD player directly into the subwoofer's LINE IN connections. Then, turn the volume level on the subwoofer all the way down. While playing a CD, raise the volume level on the subwoofer; you should hear the bass portion from the source material. If the subwoofer still duplicates the problem, then the issue may be a blown woofer or involve the sub amplifier. However, if the subwoofer functions correctly, then the issue may be with a cable, the receiver and/or a level setting.

  • How do I set subwoofer phase?

    Depending on the absolute phase of your main speakers and amplifier and the distances of the subwoofer and the main speakers from the listening position, the bass in the crossover region may be smoother if you reverse the subwoofer’s phase. Typically, though, phase is left at 0° for most applications.

    While seated in your listening sweet spot, play music with bass content that is familiar to you and then have someone switch the 0/180 phase switch on the sub to 180-degrees. This will let you determine if the bass sounds louder in your seating position. The more bass-heavy setting is where the output of the subwoofer and the main speakers are most in phase. Use whatever position (0/180) is louder at your seating location. (Note: some subwoofers may contain a “variable” phase control, which provides variable control between 0 and 180 for even more precise phase control of your subwoofer.) However, if you do not notice any difference when changing the 0-180 setting, it only means there are no issues in your room and all is fine.

  • I’m experiencing a humming or buzzing noise with my subwoofer. What should I check?

    This could be a ground loop hum/buzz or possibly a transformer hum through the speakers. In fact, large subwoofer transformers are more susceptible to a slight hum noise.

    A speaker hum at your listening location is never normal. To determine if the sub amp is functioning correctly, the best thing to do is disconnect all of the connection inputs going into the subwoofer. Keeping the subwoofer plugged into the AC outlet, turn it on; if the hum still exists, there may be a ground loop issue or a problem in the sub amplifier. In that case, the amp should be serviced or replaced. If there is no hum at that point, the issue might involve the preamp or another ‘upstream’ source component. Some common causes of a ground loop hum are cable TV connections, digital recorders or satellite dish receivers.

    If the hum issue is found to be with a cable TV coax wire, then a device called a MAGIC box possibly may help eliminate the ground loop from cable TV, or an OTA antenna. Some, if not all surge protectors have a cable or satellite in and out cable connection; try that as well.