What to do with bad recorded CDs

It depends on how bad. Try to find a better copy, tolerate it, don't listen, or adjust the tone controls to mitigate the mix. I know it's just plain impossible on some recordings. Face it, you can't make silk from a sow's ear and you may just have to toss the recording and go eat barbaque instead!

Why not a machine that can uncompress and restore the recording to its original dynamics? It seems this should be possible.
It is a shame that bad recordings can't be returned. To me after I pay $15.00 for a CD (or more) and it sound is hideous I should be able to return it and buy a new CD (not a exchange it for the same one).

Bad news for you LP fans, I've purchased just as many records that were poorly recorded as CDS.

It is not the format, it is the recording engineer, artists, etc. Some labels are noted for poor recordings while others tend to get it right.

I propose a machine (something like a DAC) that would take the digital hi rez feed and then give the user a choice on how it is mixed for car, mp3, redbook, no compression, natural dynamics, etc. This would give the enduser the choice.

My poorer recordings sound much better ripped to hardrive with EAC and then played through squeezebox/benchmark. What is unlistenable through my Esoteric is tolerable through the squeezebox.

I have some CDs that sound better than others, but very few that sound bad (<10%).

I strongly believe that the % of CDs that sound "good" on a system is a useful measure of overall system quality. If a lot of CDs do not sound good on a system,that is an indicator that a change needs to be made. The change, if done right, does not have to even be very expensive, I have found.

Bad is a matter of opinion though. The only CDs I have that I would say sound bad are those that have extremely bad dynamics, excessively limited frequency range and significant background noise in the mix. Almost all CDs on my system nowadays are enjoyable within their inherent limits. Those limits are a result of lackluster production process in making the CDs. The same truth applies to vinyl records...some are good, some are poor, and some are great.

My recent satisfaction with CDs as a source overall I can attribute to several factors I've introduced into my system over time:

1) external (tube)DAC as an upgrade
2) Audio Research Tube pre-amp
3) careful matching of amp to speakers
4) careful choice of speakers to fit rooms
5) the MIT terminator interconnects seem to let the best attributes of the components connected by them shine through, ie the ICs are not a bottleneck
6) my music server has become my prime source of digital material over CD player and has enhanced my listening pleasure as much due to convenience and flexibility factors as due to the fact that it sounds fantastic as well, as does my Denon player/recorder through the same external tube DAC.

Why not a machine that can uncompress and restore the recording to its original dynamics?

There is a pretty simple answer to that question. There are just too many variables for that to work across the board.

First, there are a lot of things that get adjusted besides dynamics. On a typical modern recording, there are dozens and dozens of mike tracks that get mixed down. Take drums for instance. There will be multiple mikes on the drums and each one may get a different adjustment for frequency response, dynamics, and position in the stereo field. (Ever notice that some drummers seem to have a 15' wide arm span?) There are dozens and dozens of signal processing effects that can be added and many have nothing to do with dynamic range.

I've got Adobe Audition that I use. Without running over to that computer to check exactly, I think it supports up to 128 channels and the processing effects seem endless.

In other words, a final recording is basically a scrambled egg and you're asking to have it unscrambled and put back in the shell.

Just taking compression, the settings for that parameter are infinitely variable in Audition and I'm sure most other studio recording programs.

As a practical matter, you're not going to find many artists or record producers who will release an unmixed/processed album. It sounds the way they want it to sound, even when it is not to your liking.