I hope you have really done double blind testing to convince yourself that indeed there are differences that you can hear.
For most people 160 kbps mp3 becomes equivalent to lossless. For few golden ears it is 192 kbps.
F00bar has a plugin that allows you to do double blind testing and statistical analysis to determine whether really you can hear any difference or is it guess work.
Yes mate, I have done numerous ones... Not double blind tests but those harmless comparisons...
The true difference I felt was when I strated to listen to more modern English music via flac files, the amount of detail, width and separation is pretty obvious....
Let me share my long term observation wrt mp3..
I have had many hifi systems in past and mp3 came into general domain in front of me in the late nineties.the systems that I owned around the time were not that great like the Panasonic ak20 and another sony one that I had in late 90s like 96 to 2002
I still have like 200 to 300 branded mp3 cds (around 60 of English songs from Sony DADC and rest from hmv of classical and Bollywood old and new ones) apart from a selected few (no idea why) they used to sound so damn average (few wer 256 and others 128kbps) no clarity (the sort that I like) that one expects from cds (obviously) hence I stopped listening to music by the end of 2005..(I realised I might have to buy something expensive to enjoy and the priorities had changed altogether at the level of family..) didn't really realise that mp3 files aren't for me.
I have so many mj songs in my iPod, and iphone all in 320kbps mp3 versions but they are so average, to listen to..(via Earbuds or via chromecast and amp) .
If the same song is listened via streaming services at highest quliaty they sound pretty good, but when you stream them in the same setup using flac files the sound is more wide and sweeter...
Just yesterday I made an audio cd of remastered hits of Ella Fitzgerald using flac files and it sounded so good, exactly like the flac files but through different medium..
Flac file >streamed via netwirk to >Google chromecast >analogue output >fosi bt20a pro >Sony speakers
VS
Flac files>converted to cda on an audio cd >played on a humble LG dvd player >coaxial output >fiio taishan>3.5mm output to rca ports of >fosi bt20a pro >Sony speakers
The sound is exactly the same (may be a tad better on audio cd, I dunno though, need to check again)
But all in all, 320kbps mp3 in my view is no match for the kind of music I like to listen to with audio cd or flac files...
How I wish I knew this back in the day and would have created an awesome setup gradually when things were readily available and were not very expensive... Discarded many things without assessing why I am not enjoying their performance...