Power Cables

Yes but as I mentioned the degree of improvement is similar. If I remember correctly you have Aurender N20 paired with MSB Discrete DAC. I would go up to Frey 2 or even Tyr 2 on a used market for the power cords. Heimdall 2 is very nice but Frey 2 is an audible step up. I have Frey 2 on pass mono amps. Nordost should be a nice match in your system with harbeth speakers.

Audio advisor , Pangea sig MK-2 awg 14  are very good for under $250 

using copper connectors far better then bright brass and 3x more conductivity

and use Cardas grade 1 Copper wire. Give him 150 hours to runin a very good value.

Wywires is running a sale. Both the Silver and Platinum Digital Series are fine cables. I started with all Silver Series throughout my system and have sold and moved up to the Platinum’s. To my ears they just get out of the way, being very transparent, and throw a wide and deep stage. Have both the HC - High Current and Digital type and on digital components the Digital build do sound better. They don’t come up often on the used market but when they do, they move so grab them when you can or wait for Alex to have a sale. 

-1 Audio Envy.

I have a couple sitting in a box in the garage (replaced them with Anti-Cables).  Contact me if you want one.

Best

Of course check the used market as there is thousands out there and thousands more made every day. Different colours, sizes, textures, gimmicks, satisfaction really depends on how many years you wanna play in the rabbit hole. With regards to the brand names, most produce their share of new product by yearly as well. May l suggest week on week off sampling with music you like, won’t seem like such a waste of time. 

Cheers