Yes there is an improvement. Whatever some other people think.
My very first turntable mod was to hard wire a better power cord onto the Basis motor. There was no IEC so it had to be soldered. It was a very inexpensive power cord. Well, I wasn't about to go cutting up an expensive one for an experiment now was I? Yet in spite of that it was a very noticeable improvement.
If a power cord is good it will be good on whatever you use it with. If not then guess what? Not a good power cord after all. It really is that simple.
I put a $500.00 Shunyata power cord on my VPI Prime turntable and heard no difference. I have that same cord on my Technics SL1200G turntable and still don’t hear a difference although it does look nice. I talked to Matt Weisfield @VPI about an aftermarket cord for the Prime and he laughed and told me the motor won’t know the difference. He was right.
The sound of a component starts with the power supply - not what comes before it! Physics 101!
Only if the power supply is perfect.
No power supply is perfect.
Whatever noise or fluctuations are on the incoming AC, some of that will always make it through the imperfect power supply.
Because: no power supply is perfect.
Therefore, the quality of the incoming AC does matter.
The same applies AC or DC. The main exception being if the DC involves a battery, and if the AC charging the battery is disconnected during play. Because essentially, as I just showed, as long as there is any connection to AC then some of the noise on the AC line is going to get to the DC. The one exception is when a battery is used, and even then only when the battery charger is disconnected from the line during play.
This isn't guesswork or rumor. This is actual experience running all these different ways.
Got rid of the wall wart and bought a linear power supply for my previous TT. And I did upgrade the power cord for it, albeit with a modest one.
Funny enough, I never bothered to A/B them. Perhaps I didn't want to know if I had wasted money...
However, it would seem reasonable to think that a more stable power supply would at a minimum provide better consistency with motor speed. And, when I sold it, it went with the manufacturers wall wart, which means I now have a very clean 12V power supply to play with:)
About to finish a heavy plinth Lenco L70 and will be using "better" wires throughout once the build is completed and its running properly.
Every little bit matters, and a big thing is just a whole lot of little things put together.
One reason for an upgraded power cord is RFI filtration. Most of us have our cords coming close or crossing other cords including speaker and other interconnects. Also,
Even though I have not tested it there might be something to the consistency of the speed. If you have a TT that governs the speed perfectly then it’s good to go. Last but not least is that most of us have an extra less expensive but good cable lying around. Those basic cables are very cheep. What if you move your power strip or conditioner and the power cable ends break off or short. It’s like owning a nice car and putting really bad lawn mower can gas it it. Not recommended.
I fitted a Furutech IEC to my Technics CH10E (PS for Technics SP-10 Mk2a) for the sole purpose to find out for myself if an upgraded PC would have any sonic improvements to the sound. Nordost V1 PC vs. $10.00 PC were used for comparison and I didn't heard any difference. This is NOT to say other TT manufacture's PS will yield the same results. Just not with the SP-10 Mk2a.
A few years ago I had to swap out the original lamp wire power cord on my Thorens TD160 because it had a small cut. Bought a fancy power cable, cut one end off and soldered the wire to the TT. Sounded ditto to the original. Unless its a hazard I prefer to retain the original cable. Helps the pocket.