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Let's suppose I'm interested in measuring the voltage response of a DUT to some imposed voltages. The DUT takes V1, V2, V3 as inputs relative to some GND, and outputs V4 relative to the same GND. All signals are below 100 kHz, and there's a 4 m run of wire. Is there any benefit in using four twisted pairs (V1, GND), (V2, GND), (V3, GND), (V4, GND), where for each twisted pair, one of the leads is bonded to ground, and the twisted pair is either stimulated (in the case of an input) or sensed (in the case of an output) by a differential circuit. The DUT can not be extended with differential drivers (it will be deep inside a cryostat at 300 millikelvin.)

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Yes there is a benefit from using twisted pair for this kind of messurement as you minimize the chance of external electromagnetic fields to induce Energy into the messurement circuit and such change the mesurement result. If you can't use coaxial shielded cable, twisted pair is among the next best solution...

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It really depends on the sensitivity of the signals, twisting them will make them less susceptible to magnetic field noise from magnetic loops creating noise. Twisted pair are still susceptible to electric field coupling (which is why ethernet uses a differential signal because differential signals are less susceptible to noise).

So it would still be good to provide a shield around the cables up to the Cyrostat if they are very low level signals (like accuracy in the 10s of microvolts or below)

But if they are digital signals then don't worry about it it will be fine

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