2 Packs Ground Loop Noise Isolator for Car Audio/Home Stereo System, Ground Loop Isolator with 3.5mm Audio Cable......

It's electronically a stupidly simple circuit any beginner could make, but the trick is containing it within a professional-looking, commercially-made housing that isn't made from a pill bottle or other reused container, and doing so for less cost than getting TWO of these for.... what'd I pay, eight bucks? nine? I have a Jeep with the aux audio port into which I have wired my amateur radio transceiver via a 3.5mm TRS patch cable. The alternator whine only came through on the receive audio, never went out on transmit, and honestly it was quite tolerable, but I really wanted to get rid of it. Knowing the circuit was a simple design, I figured it would be quite inexpensive to purchase a commercially manufactured product, and I was correct. Installation was a breeze, and fortunately I already have the radio bracket close enough I could zip-tie the filter to the bracket and keep it secured and out of sight. You can barely see it! It definitely works. After installation, I couldn't hear any whine. I'm not saying it's zero, but the engine with the tops off and windows down was loud enough that I couldn't hear it with the filter installed, whereas the whine was loud enough to hear through the engine noise with the filter not installed. I don't 100% understand the theory myself, but essentially it's a 1:1 audio isolation transformer inline that disconnects the lines electrically (DC) but still allows audio (AC) to pass electromagnetically via the transformer windings and core, thus breaking the otherwise direct connection between audio equipment and a variable ground potential (voltage on the audio ground instead of chassis ground) from the alternator. Anyway, bottom line, it works, and I have two for the same price some sellers are selling only one.

Left side sound is much lower than right in both isolators, and quality of sound is poor (less bass and treble) -- the bandwidth is very bad. The ground loop noise went down, but so did the sound quality! Doesn't do what it claims. Also, I've been using a low cost bluetooth receiver to isolate my speakers -- I thought this would simplify things. The bluetooth receiver sounds great, exactly the same as if the speakers are plugged directly into my PC. This isolator is a piece of junk -- don't waste your time.

It does get rid of annoying electrical noise and feedback, problem is your sound becomes muddy and not as crisp.

Had that low hiss in my PA system when I connected my PC to it. It was there when recorded my band. Hard to remove the frequency in DAW's. This fixed the problem. A must have and a cheap fix to improve your sound quality and save time when editing in your DAW.

I had the wise idea to connect my MacBook Pro, IPad, and Teenage Engineering EP-133 KO-II to an audio mixer so I could share all of them with one set of headphones. And yes, all are powered by USB. I quickly learned this was a perfect recipe for some kicking ground loop hum. If I disconnected two of the devices from USB power, no more hum. But I didnt want to have to unplug and replay them in to charge. A quick Google search lead me to this solution. But I had my doubts. Do these really work? Some mixed reviews. But I figured these are cheap enough to give a try. AND BOY OH BOY DID THEY WORK!!! No more hum! Clean audio from all devices through my audio mixer into my headphones. Amazing!!! Money well spent