I want to send multiple stereo audio channels over a short piece of cable, max. 2m. Naturally I'd like to keep crosstalk between L+R and between individual channels to a minimum. My first bright idea was to use a multicore audio cable, that works well but is just to thick. I can't fit it to any connectors I'd like to use and multiple connectors increases cost and looks unprofessional.
I've done some quick and dirty measurments yesterday using the multicore and using a shielded cable, type LIYCY.
The multicore excells at channel crosstalk as one would expect as each channel is individually shielded. L+R crosstalk attenuation is about 67dB. I have to say I've done the tests using unbalanced signal lines, so L and R signal are together in one core.
Now in a piece of LIYCY cable I measured crosstalk of 89dB, even better if I ground some of the wires in the cable.
The LIYCY I'm using is not a twisted pair, so am I right in thinking I'd get even lower crosstalk using a TP cable connecting one of the wires in each pair to ground?
My measuring setup looked ike this:
Audio sinewave generator @ 1kHz/1,55V/600Ohms impedance
feeding into "sending" wire
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cable under test, shield connected to ground
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termination into 560R resistors, both send and receive wires
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HP400F AC millivoltmeter
connected to "receiving" wire
Anything I'm missing here please let me know.
The crosstalk increases rapidy when I go over about 6kHz, that was expected and doesn't bother me too much...or should it?