I agree with Rich, shorter SC and longer ICs. Let's check out some data.
Imo, less than 25 foot cables, the EE who stated no sonic up to 25 feet is way off, as the data below clearly demonstrates.
I am currently using (10) 18 gauge wires in parallel, which are
only 6 foot lengths, and the perception is clearly realized in my years of testing.
Whereas DC wire resistance is not frequency dependent, wire inductance is. For comparison, the dc resistance, inductance, and impedance of various wire sizes and combo are listed below. These calculations are based on only 5 foot lengths, and at 20khz. We will interpolate to lower frequencies later. (nh is nano henries.)
Single Single Single 5 parallel
18 gauge wire 13 ga. 11 ga. 18 ga.
2410 nh 2232 nh 2162 nh 482 nh
DC resistance
.0325 .0104 .0066 .0065
Inductive reactance
.30 ohms .28 ohms .27 ohms .06 ohms
For simplicity, a single 11 gauge wire, 0,27 ohms reactance is approximately 1/7 the impedance (Z) of a 4 ohm speaker Z. The response is Down somewher, guessing around .75db at 20khz.
At 10khz, the Z is still 0,135 ohms. At only 5khz, 0,0675 ohms. Remember, this is for only a 5 foot length speaker wire.
A 25 foot length of single 11 gauge solid wire, at 20khz; we are talking 1.35 ohms reactance. At 10khz 0,675 ohms, at 5khz 0,34 ohms, and at just 2.5khz, still 0,17 ohms reactance.
Also note that while the 5 parallel 18 gauge wires equate to an 11 gauge wire in terms of DC resistance, the inductive reactance is nearly 1/5th that of the 11 gauge wire at 20khz.
Olsen's work demonstrated that harmonics are weighted. Thus the ear is extremely sensitive to harmonics being altered. (We are not discussing SPL changes across the entire audio band.) As the harmonic number rises, it takes less change to be perceived. The 3th harmonic is more sensitive than 2th harmonic, the 5th more than the 4th harmonic, the 9th harmonic than 8th harmonic etc.
The inductive reactance of the speaker wire will alter both the phase and the amplitude of the harmonics. Thus minimum Z is advantageous.
I live within 7 miles of megawatt TV stations, and no problem with interference entering via interconnects. Those ICs are not shielded. And any small 60hz hum, I simply dial out.
As I mentioned earlier, I agree with Rich, but I suppose there are some circumstances where the opposite could be advantageous.
I hope this helps one to more fully understand what is occurring in their own system.
All the best.
Steve