Power cable from wall socket to power strip

Your power cable can't make up for inadequacies on the way to your devices. At best, you can minimize voltage drop without actually improving noise pickup, a balancing act.

The two rules I live by are to keep noisy things out of my clean power zone.  That is, after conditioning I avoid any cheap wall warts used for network devices especially but also sometimes streamers.

I also use shielded cables after the conditioner to minimize noise pick up caused by crossing paths with digital signals and/or noisy power supplies.

So, I focus on keeping the after conditioning power as clean as possible, but if the area around your equipment crosses digital (i.e. Ethernet) much I might put a shielded cable before it as well just to keep as much out.

I wrote more about my views here:

https://inatinear.blogspot.com/2019/04/power-management-for-frugal-audiophiles.html

A lot depends how good or bad your power strip is 

,with yours yes a moderate $2-300 power cord will make a improvement 

personally you need to spend around $3+ on up to truly get a line conditioner 

that truly makes a big noticeable difference .

yes the AC outlet and cables make a difference .

rule of thumb as I have stated many times ,having owned a Audio store 

onky 25% goes into the total of any product ,excluding cables , this includes all parts assembly and packaging ,the rest R&D overhead and marketing,markup

if you have a $1k conditioner maybe $200 went into it then packaging , bought in volume thsts why I state $3k on up is realistic if you want Good parts quality 

and a sizable improvement . Having been into modding Loudspeaker Xovers the biggest weak spot in most speakers, and electronics , the MFG have to make a decent profit or there is no reason to be in business,

cables can have markup up to 10x the investment in parts ,they can charge any price they choose per hr for their time that's why I look for quality and value with cables , No thanks on $3k power cords for me  !!

I just removed my isotek evo 3 polaris for a $75 hospital grade power strip and the faint hum in my subs disappeared.

The main reason I decided to get rid of it was the blades in the isotek inlets are crap - all the plugs were loose.

I'm ordering this to replace the power strip https://www.cullencable.com/gold-series-power-box-6-outlet-receptacle-strip/

You can probably get one made with a longer cable if 4ft isn't enough.

Go to the Nordost website. They have a presentation explaining what they believe is the order of importance of each cable in a system. The power cable out of the wall socket is number one, more important than connectors. I believe that was part of a demonstration they’ve done at audio shows. Hope this helps.

I have found that my sound is best from my superior cables being plugged into my components. I tried my best cable from the wall to distributor, but it did not work well. Currently, my wall to distributor is serviced by an adequate, but unspectacular cable. I think it would be good to upgrade the wall to distributor cable, but I am not certain if I would notice a large improvement. A little improvement would be nice, but I wouldn't expect anything dramatic at this point.