I don't own an N20, but I have a great streamer with an excellent power supply, the Innuos Pulsar. I recently had a chance to demo the Shunyata Alpha-X NR and the Snake River Audio Takshaka power cables in my home system, using the lending library at the Cable Company. Both of these cables should be available for less than $2500 new with appropriate discounts (and even less money if buying used). I compared these two cables to my regular power cords (Shunyata Theta and Delta, as well as Cardas Clear) when used on my streamer, DAC, preamp, and Atma-Sphere GaNET monoblock amps. I found that cable changes were noticeable throughout the streaming system, but were more apparent on the streamer and DAC than on the amps and preamp.
Comparing the Alpha-X and Takshaka cables on my streamer, the Alpha-X sounded significantly better. I was particularly impressed by its balance of high-frequency air, mid-range sweetness, and low-end impact. This was achieved with realistic body and tone, without any listening fatigue. It's possible that the higher priced Shunyata cables would sound even better, but I wasn't willing to make that large a financial commitment to power cables.
I haven't heard the Alpha-X on an N20, but you might want to see if you can demo one in your own system. I did notice that the reviewer who wrote the positive TAS review of the N20 (from a few years back) was using a range of Shunyata cables in his system when he produced that glowing review. Good luck with your power cable search.
