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We do not recommend modifying the headset cable. Headset extension cords or headset "Y" cables are also not recommended. Extensions should be limited to no more than 15ft due to the possibility of capacity capacitive coupling between the microphone signal and the headset signal which would cause a loss of high frequency response or oscillation.
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We recommend a 2 pair individually shielded snake type cable to make headset extension cables out to 15 feet in overall length. Canare Cable MR202-2AT snake cable is a 100% foil shielded multichannel audio snake cable for general purpose studio applications. Each individually isolated channel consists of 2 twisted conductors under an easy-to-strip PVC jacket extruded over a foil shield and drain wire. The color striped PVC
channel jacket alleviates the need to use costly shrink tubing. Flexible, this multichannel cable is perfect for control room layout and interfacing between equipment racks, audio patch bays, mixers and tape decks.
A PDF of the cable specifications is attached below.
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