Whirlwind ISOXL Line Level XLR Inline Isolation Transformer

These seem well made to me, though I don't know where the transformer comes from. Could be an OEM USA or elsewhere, but it seems to keep the integrity of the signal. I use these in my studio between my interface line outs and my monitoring station. They have taken the significant noise I had down to nil. Testing back and forth it seems to me that the signal is 95-99% intact sound wise. The only product I would imagine to do better in this regard is the Jensen P0-2XX. Their transformer designs are the most incredible in existence, in my opinion, for audio applications requiring transparency. That unit is also $135 per channel. These Whirlwinds are only $48. I also use these to block DC phantom power that might accidentally be turned on when using a channel strip as an insert in a mixing session. Fluke tests confirm that the transformer does indeed not let phantom power DC through, though I don't know the stress factor on the transformer of the Whirlwind nor the output of the channel strip at that point. I would rather they be stressed than the capacitor coupled outputs of a very expensive interface.

I switched my home theater over to XLR connections from my processor to amps and subwoofers hoping to reduce hiss and ground loop noise (a big issue in a system running across four dedicated AC circuits). I had been unsuccessful in mitigating these issues with RCA connections to my subwoofers with a variety of products. XLR connections almost got the job done by itself - all that was left was a faint hum that only occurred when my projector was turned on with an HDMI connection to my processor. I initially tried using ART transformers that I had on hand on the inputs to the subwoofers but they still left a faint hum that was audible from my listening position 12 feet away. It was not too distracting but I tried these to see if they could do better. There is no trace of hum that I can hear with these and I am now experiencing the lowest noise floor that my theater room has ever had.

Well...if i were to judge its effectiveness from 1 to 10.....10 being perfect. I would say its effectiveness is a 7.5 It did indeed knock out the majority of hum as a result of a system gnd loop, but not completely. This is very difficult to do though. Would recommend.

This is an audio transformer that provides galvanic isolation. It also interrupts the ground connestection (pin 1). The transformer windings are shielded. It is useful for connecting balanced to unbalanced device. Unbalanced connections (different impedance to ground) can turn common mode noise into normal mode noise. This transformer fixes that, if you put it close to the unbalanced side. Often, just interrupting the ground/shield at the destination end works as well. Shield interrupting devices are a lot less expensive, try that first. Note: it's an isolatolation transformer.-- it will not pass phantom power.

complete waste of 50$ the hum on my sm7b sounds even worst with this product. Don't waste your money!