It's really not that critical, just don't use those that comes with the devices which are very thin. Just get any thicker coax type and it's good enough. Just make sure the connectors fit tight and won't fell off.
The more important thing is DO NOT get cable longer than is needed. This is very important if you worry about cable capacitance, loss and all that.(not that I think it's that important) I use a lot of the 18" cables if they can reach.
For example, the best cable is say 15pF/ft. The worst cable is 40pF/ft. If you use 18" of the worst cable, it will be 60pF of capacitance total. By comparing to 6ft of the best of the best cable, it's 6 X 15pF = 75pF total. so an 18" bad cable has lower capacitance than the best and most expensive 6ft cable. This is the same as resistance, inductance and everything else. Keep it reasonably short and don't worry about it.
Don't listen to people that claim what metal the cable is made of and all, it doesn't matter. Input impedance of preamp and power amps are very high, you don't worry about needing a lot of drive. Most modern devices ( DAC, preamps etc.) have very low output impedance, a little capacitance, inductance etc. will not affect the sound. These preamp low level signal is nothing like speaker cables that has to drive down to 2ohm load where inductance becomes importance. It's NOT that critical.
Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
Last edited by alan0354; 04-25-2019 at 08:21 PM.