Is it me or MP3?

Now I know my old ears have been through a lot over the years but ...  I have noticed on some mp3's, I have exported from Sonar using Lame (192bps, constant bit rate), some of the quieter background parts get even quieter after the export.  Even to a point where they are almost gone??  Anyone else hear this?  When I export I am never sure about dithering but I export Power2 16bit out of habit.  Is this me or mp3?  Hey good song title.

try CDEX

Or you could just get with the times and crush the life out of the song until there are no quiet parts to worry about. I think the example above is using SONAR's "sausage" setting... LMAO!

Hi,
 
Can't say I have noticed that but now you got me thinking ... I usually just mp3 the CD's off Windows Player on my computer, and so far, all the rips have been fine, as far as playing them in my car is concerned, including Tangerine Dream, but I have not done any Klaus Schulze in my car, for example.
 
I imagine that I would have noticed something like that a long time ago, as that is not good ... and I find it totally strange that Sonar/Cakewalk, would use a cheezy mp3 tool, and do something that poor ... you're talking about a major program/DAW, using a sub-quality tool! That doesn't add up, and I wonder if something else is the issue ... now, I'm even concerned that using Sonar is not a good idea, considering how much mp3 stuff I do, from my CD's. I'll have to try it with a few pieces of my own stuff ... but I find this very scary! And bad news!

I've got some old ears, too. And a high frequency hearing loss in the left ear (thank you, Led Zeppelin ), so take the following with a grain of salt...
 
I was doing some tests ripping the same CDs and converting the WAVs to MP3s at different sample rates (LAME codec) and playing them back in different environments. I wanted to see if I could hear differences.
 
For me, anything below 192K (all constant; I never use VBR) lost way too much source material. Note that I don't listen to simplistic pop vocal type material.
 
I noticed some more subtle differences between 192K and 256K. 320K seemed to add nothing except larger file sizes, until...I played it in the truck I owned at the time that had a great sound system and a really good (fast/accurate) subwoofer. THEN I noticed the difference between 256K and 320K...the low subharmonics were significantly attenuated at 256K compared to 320K.
 
There's also the "deconvert" aspect. I use LAME to convert to whatever deconverter is in the player I'm using (my Android phone or built in to the CD player in the vehicle (playing a data CD with MP3 files in folders)). I've gotta wonder what that does with the dynamic range vis-a-vis the original. I suspect the decoder brings up the noise floor. It's almost like we need a Dolby codec like the original one for cassette tapes...record with a bias and push that bias down (along with the noise floor) during playback.
 
Or am I really from outer space?