I'd like to suggest a more systematic approach to answer your question, because the direct response is, indeed, "it depends." As someone wrote early in this thread, the answer to your question is not independent of your current audio system (components, sources and room). First try to answer the question, "what is the weakest link in my audio system?" The answer to that will probably prioritize your approach. Improve the weakest link, then repeat the process. Here is the rough sequence for me: new speakers, bi-wired the speakers, network streamer (with DAC), new integrated (with better DAC), better speakers, room acoustic treatments. Each step improved the SQ. Along the way I swapped out all cables and added a power conditioner but I didn't notice a significant improvement in SQ. So, OP, what do you think is the weakest link in your sound system, and why?