“I have wired my own cables, but I still always seem to end up with a few that are too long. I realize they should stay as far from power cables as possible, but is there any better way of dealing with the length rather than coiling them?”
Coiling up audio wires is not the greatest of ideas in general. In many situations, it is easier to have hum induced into coils of wire than straight lengths or random ‘wads’ of wire. When you coil audio wire, you are building a transformer or coil. It’s a very weak transformer so it usually it isn’t a problem. We’re not suggesting you redo all your wiring if everything sounds okay, but this is something to be aware of. It is worth noting that I have seen neatly coiled piles of electrical extension cords get so hot they caught on fire before. This was no doubt partly due to heat generated from the energy converted to heat from the inductance of the coils. In high current applications (stage lighting) you need to pay particular attention to this. Spread the cords out so they can cool and do not react with one another.
So what can you do besides coiling wire when you have too much length? Well, basically the choices are to make it shorter or coil it up. However, there is more than one way to coil wire. A random ‘wad’ of wire is best at rejecting unwanted signals, however, most users aren’t anxious to go this route. We suggest coiling your wire in a figure 8 pattern. The two loops of the figure 8 are wound backwards from one another and will pretty much cancel each other out. For sensitive signal cables this is usually enough. Try not to run them alongside power cables. The magnetic field generated in a simple, straight piece of wire can be strong enough to induce a small voltage in a wire lying alongside it.