Which cable is most important to spend money on...

You can do EXTREMELY well with inexpensive speaker wire and power cords, but not with interconnects. The important issue is to have power delivery/noise control and room acoustics worked properly prior to auditioning anything. Regarding the *order* in which cables should be upgraded I agree 100% with Thomas Heisig.

***

Well, Robert Ridgestreet's answer is theoretically correct. They day he can implement it (that is, marketing) for the average audiophile he'll become a millionaire! In the real world budget where I live, working on power delivery/noise control using 220V/110V isolation transformers/filters allows me to use much cheaper but still well designed power cords. I *am* waiting to save some money to purchase power cords from a friend who upgraded to Ridge Street throughout his system. He says they're the best--and this is coming from a guy who'll spend $2K on a digital IC. I'll settle for second best...and consider myself fortunate.

What a life!

***

>>Everything is system dependent<<

I've learned through experience that phrase is a cliché used to justifiy not so good stuff/choices...or stuff/choices that compensate idiosyncracies/biases.

Robert Ridgestreet has designed his power cords to address something no one has, to date. Please read and or call tha man.

***