Why don‘t servers/players incorporate polarity switches


Why is it that most digital servers don‘t incorporate the ability to switch polarity whereas in my experience only ~20% of recordings are in polarity? It‘s a standard feature in Puremusic and other PC/Mac based software and really makes a noticeable difference in sound quality. So much for progress and golden ears...
antigrunge2
Some listeners are better at noticing this, as are some systems better at picking it up... And so true that a single recording can have some but not all aspects in a diff phase.

my DAC has a switch. I like that, as I can sometimes easily tell. Other times I have to switch it back and forth to tell. But it does really help, other times, seems to not mater as much. Maybe those are the recordings with both going on.
70% of the time it can be heard every time. I agree the difference can be heard and I used to spend the time but I gave up years ago messing with polarity. Both my preamp and DAC have switching. Problem is often the entire recording may not be inverted but possibly in the studio a mic or one or more piece of equipment may be out out of phase from the rest but not all. I find the more my system has become refined the less I mess with some of these tweaks but might revisit as both remotes have invert button so why not. Cool thing is on my preamp from the vents on the lid, the blue LED’s turn off when polarity is inverted so it’s easy to see from my seat.
I was at a hifi demo of some fancy Wilson speakers a year or so ago. One of the store's sales people could tell the difference of polarity right away. He tried to demonstrate it to the customers, but unfortunately for me I was not able to tell. Perhaps after some time it would be something I could notice. This just goes to show there are things in audio that others can hear even if we can't at the time. I don't think he was making this up. He could walk into the room and would say "switch the polarity" which of course was just a button on the remote. Since each recording could be about 50/50 chances you would be switching this feature a lot as we were sampling all different kinds of music. If you can't hear it, that does not mean it does not matter. Kind of like the tree in the forest.
Many preamplifiers include this function. I don't see any advantage to having the feature in a server.
@lalitk 

Your comment shows your profound ignorance on this topic, lest you care to elaborate
@jaybe 

As I mentioned, I had this feature on Puremusic and am missing it now on my server/player. Also, there is a distinct split in recordings out of polarity which I estimate to be 80/20. In any case your comments seeks more to take a swipe at me than advance the thread.
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Wonder if the OP is aware that some audio equipment is out of polarity as a result of the design. And they usually don't tell you.

Wouldn't it be funny if the OP's bad sounding CDs were because of his system. 50/50 chance.
“It‘s a standard feature in Puremusic and other PC/Mac based software and really makes a noticeable difference in sound quality”

Your answer lies within learning the differences between mass produced PC/Mac’s and streamer/server’s designed for the sole purpose of audio only.
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As a simple albeit cumbersome check you can change the polarity of your speakers and listen to the same piece of music
Recordings out of polarity have a dulling of the leading edge of notes that is quite distinct. (e.g. woodwinds sound like they are sucked in rather than blown)