When a power cord could obviously affect SQ

@mclinnguy 

You don't need to buy anything to find the answers. Borrow it.

Stop thinking and start listening

Yeah, I should stop thinking while listening.

Your advice is not so easy to follow in Australia!

@richardbrand 

Shop, or er, borrow local, this list is a couple of years old so it may be more extensive currently: 

Cables from down under

I have read good things from Christiaan about Mad Scientist, see what Bob's lending policy is, or find a dealer who has them: 

https://www.hifi-advice.com/blog/review/cables-reviews/analog-interlink-reviews/new-mad-scientist-ranges-black-magic-ultra-and-black-magic-gold/

Yeah...you MUST have a "resolving system" to reveal the magic inherent in "special" power cables. I have a few of those cables I've gathered over the years and compared them (I actually did this so you can trust me!) to the cable that came with my Pass XA-25. The supplied Pass cable sounded exactly like the other cables (I currently use an AQ Powerquest 707 because it has plenty of outlets and fits in my rack) which means I may not have such a resolving system (I do have a couple of bespoke-ish noise killing power supplies), or the power cable industry is immersed in silliness. I assume the latter.

@mclinnguy 

Shop, or er, borrow local, this list is a couple of years old

I went to the recent Sydney HiFi Show, specifically to buy a balanced interconnect cable.  Nobody at the show was selling cables.  Two exhibitors did list Lenehan speaker cables, but the brothers Lenehan have split between cables and speakers.  Your list of local Australian manufacturers is interesting, but local HiFi stores tend not to stock any power cables except Isotek.

I don’t want to dilute this thread, which is about power cables.

There is a very interesting article in TAS The Great Proliferation: How High-End Audio Grew as a Global Industry - The Absolute Sound.  The article attempts to count the number of manufacturers worldwide active in the market, and classified by their primary product line.  I quote

The fastest growth is around the system 

Cables, power products, and accessories grew from a very small category in the 1960s to an estimated 400 companies in 2025. Racks, isolation products, and acoustic-treatment manufacturers increased from approximately seven to 190. 

Some of this growth reflects genuine technical specialization. As systems became more expensive, owners became more willing to address electrical noise, vibration, equipment support, and room acoustics. Measurement tools also made room problems more visible. But barriers to entry are comparatively low. A cable, footer, equipment platform, or acoustic panel usually requires less capital and engineering infrastructure than a loudspeaker, amplifier, or streamer. Products can be manufactured in small batches, sold at high margins, and shipped internationally. 

This makes accessories the easiest part of the industry to enter – and sometimes the hardest part for consumers to evaluate. The category contains useful engineering, luxury craftsmanship, speculative claims, and products whose prices bear little obvious relationship to production cost. Its growth reveals both the vitality and the vulnerabilities of the high-end market. 

The conclusion is fascinating: the hardest part for consumers to evaluate. The category contains useful engineering, luxury craftsmanship, speculative claims, and products whose prices bear little obvious relationship to production cost. Its growth reveals both the vitality and the vulnerabilities of the high-end market. 

as many people have said the recommended upgrade from the manufacturer is a great place to start
 

The reason that 6 feet of power cord matters is because we're dealing with alternating current that vibrates not direct current that flows 

if it was a direct current issue coming from 100 miles away, it would be a different world, but with alternating current, we're talking about a vibrational AC wave in the room and that 6 feet of power cord is an antenna

for noise above human hearing

why do we care about noise above human hearing? Because it affects the shape of the AC wave

and that affects the power supply

and that IS audible.

the better your system the more obvious it will be, but as a user of Shunyata research power cords, those are obvious in any system