It depends ...
signal level, impedance, EMI level/type, acceptable cost/performance
properly terminated sheilded wires will have better electrical performance in nearly all cases
ribbon -with alternating gnd-sig-gnd layout can be pretty good in some applications the cost/assembly savings wins over terminating many sheilded wires especially when electrical performance differences could be way below source or amplifier thermal noise limits
signal level, impedance, EMI level/type, acceptable cost/performance
properly terminated sheilded wires will have better electrical performance in nearly all cases
ribbon -with alternating gnd-sig-gnd layout can be pretty good in some applications the cost/assembly savings wins over terminating many sheilded wires especially when electrical performance differences could be way below source or amplifier thermal noise limits
Ribbon vs. Shielded
Consider the type of signal that needs to be transported and the environment it is in. Sticking to audio signals below 30kHz-ish, you need to consider whether it is a sile ended signal with a return via GND or a differential signal that uses GND only as a voltage reference. Single ended signals beg to be shielded in noisy environments, especially on high impedance nodes. It is easy to develop noise voltage on high impedance nodes. Differential audio signals don't need as much shielding. If properly routed, which means keeping the two signal lines close together in your PCB layout and on connecting ribbon cables, no shielding is needed. The noise impings on both lines in the same amount and subtracts out at the differential receiving point. At higher frequencies above the audio band this may start breaking down a bit, but that is not relevant here. Digital signals need another approach, but I think you were talking about routing analog audio signals in your question.
Consider the type of signal that needs to be transported and the environment it is in. Sticking to audio signals below 30kHz-ish, you need to consider whether it is a sile ended signal with a return via GND or a differential signal that uses GND only as a voltage reference. Single ended signals beg to be shielded in noisy environments, especially on high impedance nodes. It is easy to develop noise voltage on high impedance nodes. Differential audio signals don't need as much shielding. If properly routed, which means keeping the two signal lines close together in your PCB layout and on connecting ribbon cables, no shielding is needed. The noise impings on both lines in the same amount and subtracts out at the differential receiving point. At higher frequencies above the audio band this may start breaking down a bit, but that is not relevant here. Digital signals need another approach, but I think you were talking about routing analog audio signals in your question.
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