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Old 04-16-2018, 11:58 AM
BobTurner BobTurner is offline
Join Date: Dec 2011
Location: Livermore, CA
Posts: 5,622

Originally Posted by Abbygirl1 View Post
Bob, could you explain in a bit more detail about the use of the resistors?
If you just tie together the headphone, SL30 output, and IPad output wires, most of the IPad current will flow into the SL30, not the headphones. And most of the SL30 current will flow into the IPad, not the headphones. Technically, one would say that the SL30 output has a low input impedance. To prevent this, put a resistor (200-500 ohms) in series with each output, before connecting them both to the headset. This will limit the unwanted current flow back into an output. It will also reduce the desired signal levels to the headset, so you’ll have to turn up the volumes (compared to having just one device attached). The proper way to do this is to spend $5 on an op-amp based mixer, which isolates each input. But for just two devices, there’s a good chance the resistor trick will work.
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