• Most, but not all, problems with a humming subwoofer are caused by ground loops. If your powered subwoofer hums due to a ground loop between amp and sub, this transformer will fix the problem by breaking the ground connection while allowing the signal to pass through..
• This transformer will NOT fix hum caused by other causes, e.g., power supply issues within the sub, ground loops between devices other than the amp and sub, induced hum from power cabling placed too close to the subwoofer cable. See troubleshooting tips, below..
• Comes with instruction sheet describing causes of hum, and how to track it down and eliminate it. If this transformer doesn't fix your hum issue, this means something other than a ground loop between amp and sub is responsible for the problem -- and you're welcome to return it for a full refund..
• Works with any powered subwoofer with an RCA-type (unbalanced) input; no separate power required..
• Made in the USA..

• Imported from USA.

Blue Jeans Cable Subwoofer Isolation Transformer / Subwoofer Hum Eliminator A good subwoofer can transform the home theater experience by adding a movie-theater feel to your surround sound system. But a powered subwoofer, built to amplify low-frequency sounds and effects, is also susceptible to one of the most vexing home theater problems: hum. Troubleshooting Subwoofer Hum: There are a few possible causes of subwoofer hum: (1) internal noise from the power supply, (2) induced hum in the subwoofer cable, (3) hum getting into the signal path prior to the subwoofer cable, and (4) "ground loop" hum from a difference in ground potential at the source and the sub. This transformer will eliminate (4), the most common cause of subwoofer hum, but will not resolve the others. Specific troubleshooting tips: - Cause (1), a bad subwoofer power supply, can be checked by simply unplugging the input cable from the sub and seeing if hums with no input. - Cause (2), induced hum in the subwoofer cable, is normally caused by the cable being too close to power cords -- check cable spacing. - Cause (3), hum getting into the signal path prior to the sub cable, is harder to diagnose, but usually the way to proceed is to test what happens when you switch or disconnect individual sources from your amp. If the more common ground-loop issue, (4) above, is your only problem, this transformer will resolve it. This isolation transformer is a quality, US-made audio transformer which eliminates the need for a straight-through ground/ground connection between your receiver and your powered subwoofer. With the grounds on both sides isolated from one another, ground current won't flow down the shield; the result is elimination of ground loop hum. We recommend it be used with Blue Jeans Cable LC-1 subwoofer cables, which are heavily shielded to reduce induced noise, for a truly quiet, low-noise-floor subwoofer.