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    Monoprice 4 Channel Ground Loop Isolator
    Product # 6909
    Out of Stock ETA: TBD


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    Browse 1 question Browse 1 question and 3 answers
    Will this eliminate hum/buzz for home theater subwoofer?
    Riz P on Aug 29, 2017
    BEST ANSWER: Ground loops are troublesome when hooking up audio equipment to TV, Stereos and Computers. It appears as an AC Hum at 60 Hz in the US. By putting isolation transformer along you connected sub-woofer, if a ground loop is the cause you will have isolated the ground path between the equipment. The should stop. Give it a try. Product is a good deal and solved my problems .
    4.1 / 5.0
    43 Reviews
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Star
    Removed Hum
    I have two devices connected to my hdtv that were causing hum. The audio connection from my pc generated a very noticable hum. Ditto for the audio out connection from the tv to my Vizio sound bar. Connected both thru the ground loop isolator (since it has two stereo channels), and voila, hum gone. Great product.

    PROS: Removed hum.

    CONS: None
    April 11, 2012
    Happy and Happier
    Monoprice delivers: A great product, at a great price, and delivery can not be faster.

    I am impressed.

    PROS: Happy: Eliminated the humming from my PC to stereo connection.

    Happier: I ordered at 9:45 AM. It arrived the next day by 11:30 AM.

    CONS: None really. If I could think of anything to make this experience even better, I would like MONOPRICE to show all the products that can work together when you place your order. In this case a 3.5 mm Male to RCA cable that I didn't realize would make the perfect complement to the ground isolator.
    December 28, 2012
    Groundloop Not for A/C
    Apparently this is used for car audio, and searching for reviews I found that it could work on A/C too, but in my case it doesn't solve my problem. The buzzing increases and a radio station suddenly sound through my speakers, LOL!!!! Maybe next time I install a car audio system I'll used it.

    PROS: Neat and a great price for a 4 channel isolator.

    CONS: Doesn't work on my Dj Equipment.
    January 17, 2013
    Solved my interference problem
    I bought this hoping it would solve an audio interference problem that occurred whenever I attached my notebook's audio output to my stereo. It wasn't a 60Hz hum more like a digital "hash" noise (clicks, pops, and buzzes) that increased whenever the PC did something like read its hard drive, or transmit data over the WLAN.

    This product completely eliminated the noise. Since the problem was so frustrating to solve (I had tried grounding the PC, changing cables, etc.) I was amazed with this result.

    Next, I plan to use the additional pair to connect the tape out from the stereo to the PC's audio input. Haven't tested that yet, but based on the above I'm optimistic.

    PROS: Well constructedhas those finished "wet look" plastic cables (not sure how to better describe them, but I've purchased other cables and adapters and have always been happy with whatever type of plastic this is). 4 channels (two stereo pairs). Works well, looks good.

    CONS: It would be nice if the cables for each pair were labeled (though you can easily look at the circuit trace on the bottom of the board to make sure you aren't mixing up the pairs).
    April 29, 2011
    Worked like a charm. I was relatively certain it was a ground loop hum in my audio equipment beforehand though. Audio sounds fine through it, reduces the hum to my sub by 95%. Awesome.
    June 7, 2011
    At my Church we were having problems with a buzz coming in on the sound from the computer to the mixer. Put this between the computer and board and the buzz is completely gone!

    PROS: It works

    CONS: None
    December 28, 2012
    excellent value with some caveats
    I needed to provide ground loop isolation on 16 stereo line connections for an in-home audio distribution system and this was a very cost-effective way to accomplish that. Overall a great value as long as you can avoid AC interference on the leads and take the time to mark the L & R leads in case the identification bands fall off which they are very prone to do.

    PROS: Outstanding value for the money.

    CONS: 1. The lead in/out lines are not shielded so they must be placed well away from AC sources (e.g. transformers and power cords)

    2. The bands identifying the red & black lines are poorly glued to the connectors and easily fall off. Many were halfway off when I opened the package. I had to separately mark the lines so I would be able to tell in the future which lead is which.

    3. On the large side. Much larger than they need to be with a lot of unused space. Appears they leveraged an existing enclosure rather that building one appropriate for containing the 2 transformers.
    June 17, 2014
    Worked perfect... for 24 hours.
    If I had written this review yesterday morning after installing the product, it would have been an unreserved 10! I was so thrilled to get rid of the alternator whine in my Ford Expedition. I bought this isolator several months ago, but had been procrastinating on the installation because I didn't want to pull my in-dash stereo to get to the wiring. Then I found out that I could also install it in the back of the vehicle next to the amplifier, which was much easier. Everything worked great and I was completely satisfied.

    Went out this morning to run some errands with my wife, sounded great for about 45 minutes, then all of a sudden the whine came back all at once. I have no idea what happened or what caused it to stop working. Very disappointed.

    PROS: 4-channel
    Perfect length cables

    CONS: Lack of labeling to separate each plug
    Only worked for 1 day
    September 11, 2012
    Item does what it is supposed to do. The shipping time to get this was too long in my opinion. If I want something quickly I'll use ebay or amazon.
    December 29, 2014
    Crystal Clear
    I purchased the Radio Shack Ground Loop Isolator and had some disappointing results (sorry RS). I would still get some pops and buzz when turning on my amp which is connected to my HTPC. Found these at my favorite place to shop for electronics, MONOPRICE, and once again my expectations were exceeded in price, performance, and delivery. MONOPRICE ROCKS!

    PROS: Silent is golden! No perceived signal degradation. Affordable. Good build quality. 4 channels instead of two. Heck, I even like the color and the see through enclosure which reveals the circuit board...appeals to the geek in me. :)

    CONS: Like others have written, you have to track the inputs to the correct outputs but unless you are a complete incompetent it's not really an issue.
    November 12, 2011