There is a table in that article that tells you how long can be a cable of given gauge to power speakers with given impedance.
Momentum are 16 Ohm, and their stock cable is 5 feet long.
There is no entry for 16 Ohm in that table, but I have done some simple calculations based on one of the entries, and I have picked this one: 2 Ohm, 20 AWG, 5 feet.
The cross sectional area of 20 AWG cable is 0.52 square mm, and the Momentum 16 Ohm are 8 times 2 Ohm. So cable needs to at least have diameter equal square root of 0.52 divided by 8.
0.52 square mm / (16 Ohm / 2 Ohm) = 0.065 square mm
sqrt(0.065) ~ 0.26 mm
So each wire needs to be 0.26 mm thick for 5 feet cable. Momentum stock cable is 2 mm thick with insulation and there are three wires inside.
Let's assume Sennheiser did proper calculations and wire is just fine (which I doubt). But what happens with these three wires after time passes?
The cable with TRRS jack has four wires and it's also 2mm with insulation. The way TRRS is wired makes it even more suspicious.
According to sources one wire should go straight from jack to left transducer, while other wires are split in pilot into to parts.
So current has to flow from wire through some stuff in pilot, and then back to wire and to right transducer. This doesn't sound very promising.
I am not advocating here buying expensive cables, but for me stock cable looks too thin, and unreliable. I would prefer it to be twisted pair, then each wire would be separate. This doesn't have to cost fortune. At the end of day one can make such cable himself by simply twisting three cables. The only issue is small 2.5mm jack, and high precision soldering.
