The greater the capacitance per metre the more top end you will lose, as essentially, the cable is acting as a tone control; the longer the cable, the more top end roll-off you will hear.
Almost all FX Pedals change the high impedance signal from the instrument to a low impedance signal which is not subject to deterioration by cable capacitance. So, provided the effect is turned on (i.e.and not bypassed), you do not need a low capacitance cable to link your FX. If however you have a series of FX with true bypass and you sometimes bypass all the FX, you will need our cable on every connection and onto the amplifier.
I have been working for years to sort this problem out as you will see in my four-part series search for the ultimate tone :)
It's been a long process and some years ago I started using George L's cable, which at the time was the lowest capacitance cable out there. This is great sonically, but the connections can be unreliable and the cable easily damaged.
Supertone has sourced the lowest capacitance cable in the world, even lower than George L's and manufactured by SOMMER Cable in Germany.
It is rugged and worthy of any stage and Supertone are putting these together ourselves using a choice of Neutrik angle or straight gold plated 'silent' jack plugs.
There is lots of bullshit out there on this subject and people charge crazy money for cables!! These are the best out there and have deliberately kept them within the financial reach of the working musician.
Treat yourself. It's the cheapest and most effective way to improve your tone!!!
P.S. Message me if you want chapter and verse or a bit more information. If you are a tone geek, why not join our Supertone Products Facebook Group - it's full of people like us :)