You'll find circuits that operate in the RF bands, even pretty high ones, that have twisted wires and other things that increase inductance and capacitance. In high-frequency work, it naturally begins to have an effect. When you do alignments on a radio, if you move components around you'll affect the alignment. So the wires and parts should be in a fixed position because those parallel paths and twists and bends have an effect.

But for audio, it becomes a little less of an issue, particularly in the output circuits. If you're running low impedance circuits at low frequency, inductance and capacitance have to be huge to have any reactance. The inter-element inductance and capacitance between paths have little effect. But when impedance is high, the effects start to become more and more in scale, particularly as frequency goes up. If impedance is high enough, even relatively low frequencies might be influenced somewhat.

All this strays a bit from your question. If you're talking speaker outputs, then the best splice is to wrap two wires together so that they are a good connection even without the solder, and then heat the ends and melt solder to flow uniformly over them. That will protect the joint. If it's preamp level stuff, try to limit connection path length and keep it shielded as much as possible. Twisted pairs are good where shielding isn't possible.