Naim recommends 3.5 meters minimum for proper inductance and capacitance.
Naim is an unusual situation. They traditionally designed their amplifiers with a certain amount of impedance expected in the cables. Their older amplifiers could become unstable without it. Amps built by everyone else and pretty sure the newer Naim amps do not need this to be stable so this recommendation does not apply.
In regards to shorter is better, I once had a set of monoblocks and took it to the extreme by configuring it all so the speaker terminals were very close to the amp binding posts and used very short jumpers, a few inches. It sounded horrible. Shrill and basically unlistenable. Longer cables made it sound great. I repeated it several times and there was no doubt a huge difference.
I only bring it up to reinforce what many others have said.... it depends. The only way to know is to try it.... I know that isn’t much help but it is the reality
