It's Simple


Cables have properties Inductance L, Resistance R and Capacitance C.
Ditto loudspeaker, connectors, electronics in and out. 

LRC are used to create filters aka Tone Controls.
Filters cause amplitude and phase changes.

Cascading LRC creates a very complex filter.

Another's opinion on a particular cable may not be valid unless they have a very similar system.
128x128ieales
The varying degree can range down to 0. The less it matters, the fewer who should care. Some will care no matter what because individual perception itself is a HUGE factor always! Maybe the biggest!
@shadorne  
“faithful to the source recording”
Ain't no such thing. Sound suffers the death of a thousand cuts. I once missed out on a Grammy nomination because the record company head ordered Bernie to add 3db of compression overriding the producer and I. The disk you get is often not the music recorded. A pal on the nominating committee said we were a shoo-in but for the compression.

I recently did a bit analysis of Fagan's Nightfly. Pals and I have pre & post IMEI versions covering multiple decades. The post version I have is markedly inferior. It has been eq'd and compressed. Happens all the time that marketing types order changes and 'engineers' who've never been in a studio make arbitrary changes because "Anything I do will make this .... better"

I recently purchased a replacement Moby Grape CD. It sounds like it was made from MP3. Record companies can be butchers!

Speaking of MP3, either it is turned off or I leave. Here's why:
http://www.ielogical.com/Lossy/LossyEncodingSoundsBad.html

A high fidelity setup will allow you to hear what the mastering engineer intended.
The mastering engineer is just another colorist in the chain. Depending on the project, Doug and his setup could work wonders. On another, not so much. His 'Direct to Disk' work was incredible.

If the budget would support it, we'd master at Doug's, Bernie's, Steve's, etc. The monitor system itself alters the sound. It could expose or mask, turning a feature into a flaw or vice versa. Sometimes, we'd cut multiple lacquers [refs], each from a different manufacturer, at the same place. The lacquer itself added coloration. As did the tape deck, desk, EQ, cables and cutting head. 

Once the refs were cut, they were checked in the studio for fidelity to the mix and also on multiple home systems. On cheap systems to make sure they would play and mega systems to make sure they had as close to studio quality sound as possible. On one project, Side 1 was cut at one lab and Side 2 at another.

If the artist had enough clout, we'd request the pressing be done at a specific plant and limit the number of impressions per stamper.

All of the above added far more coloration than decent cables.

Sadly today, too much "music" is done on a laptop and for a phone.

@people - please be civil.
dave_b

big fan of Transparent cabling here. I have only heard the MM2 series.
Give a shout-out for your local Transparent dealer/retailer.
Happy Listening!