Hi,
Without any doubt Triode Wire Labs cables. The lesson I've learnt after buying them is that people in most cases don't need a new amplifiers or new speakers, just a good power cord or good cables.
For the Dac the "Digital American" is highly praised, I'll get one soon.
At the moment I own "American cable" which is for speakers. It totally changed the dynamic adding a lot of energy, engagement and a very meaty sound.
Then I bought the interconnects and power cord "Seven Plus" for the amp and it outperformed anything I tried before. The bass is totally different, more defined, natural and deep. It felt like I bought a new amplifier indeed!
Plus Pete is a joy to deal with:)