Haha
Well you know the one and only reliable way to rule psychology out of the equation...
But despite my previous post, I suppose it's conceivable that a particularly poor cable could have an audible impact, although the electrical engineers here may be able to disabuse me of this belief too.
On two instances the Audioquest cables proved to be much better then stock market cables :
On the main floor, living room floor standing speakers with the top being passive mid/high section, active closed subwoofer the bottom part. The subs wood produce a consistent hum/buzz sound, faint, never the less audible for me. When i unplugged the hdmi cable from tv to amplifier the hum/buzz dissapeared. At first my impression was that fault comes from the tv. I contacted technical service (philips led tv), they came to investigate, they also heard the hum/buzz but didn't know what to do. They asked to take tv, amp and speaker to their technical department to investigate and eventual come up with a solution. Two week later they were brought back with an invoice stating : incompatible devices, no solution. At that time i was using generic cables. A friend visiting also heard the hum/buzz, went to his home and came back with two power cables (shielded Audioquest NRG 2 and two coax cables audioquest Forest, we connected those to the Subwoofer part of the floor standers and the hum/buzz was gone.
In my man cave (attic converted to computer room with audio/video corner) the settup is from computer to usb/spdif converter to dac. Audioquest cables. No problems here. Until i wanted to use an additional output from usb/spdif to another dac placed in the audio/video setup. A 5 meter Audioquest cable not being cheep i used a generic AES EBU connection. Every 2/3 minutes i would have a short hickup in the signal. Replacing this connection with a 5 meter AES EBU Audioquest Big Sur cable solved this problem.
So for those that ridicule the use of better cables (agree pricier than generic) the improvements i heard were not subjective or placebo. These were clear audible upgrades.
As stated above, i believe in good constructed/engineered cable. I do not believe in exotic expensive cables. Apart from the fact that the power cables are considerably more expensive, they are shielded, the interconnect used in my system are not that much more expensive than a good generic market cable.
Ps : heard the audioquest cables with battery in my setup and could not hear any difference to the audioquests i use.