How to improve my low quality audio?

Hello, people. I need help.
I got some videos with really bad audio, which causes headache. I am just used to do simple stuff with Audacity (converting audio, cut some parts, things like that).I’ll attach in the of the post a sample extracted from one of my many problematic audios (it’s in Portuguese).

The audio is awkward. I’d like to improve it, but I have no idea of what I should do. The only “advanced” stuff I know how to use is noise reduction (by selecting the noise and removing it, don’t know if there is any other way), but I don’t think if it’ll be useful here. Sound seems sometimes very muffled and sometimes it seems to pierce your eardrums. I don’t know any audio slangs to describe it better.

Please listen to it and help me to know what features/tutorials/plugins I should use to improve it as best as possible. If it’s even possible, of course.

There’s plenty of echo on that , there’s no way of removing echo from a recording , sorry.

In future try turning off (unchecking) “software playthrough” in Audacity preferences (Ctrl+P) to prevent the echo being created …
uncheck the box I've coloured yellow.gif[b]Why_is_there_a_delay_or_echo_when_listening_to_what_I_am_recording[/b].3F

If that doesn’t stop the echo see the link below …[b]if_they_were_made_in_a_tunnel[/b].3F

Please ignore the echo. It’s normal from the original recording (it was not recorded by me). Here is other sample.

I’d like to focus on making this unpleasant sound “cleaner” and “more pleasant” to ears. Deepest sounds are too muffled, sharp sounds are too high and hurt my ear-drums. It surely causes headache if you listen to it all the time.

I’m out.

The posted sample was overly Noise Reduced and I can hear the wobbling sound in some of the words.

Anything I do to make the woman’s sound less harsh kills the man’s voice. So even if I do find a filter to help, you would have to go through the show one dialog line at a time and only patch the woman’s voice.

I’m guessing somebody held their cellphone up to a radio or TV and pressed Record. That means there’s a list of errors in the clip.

Open the show and select a portion of it with both voices (like to gave to us). Effect > Equalization…: [X] Graphic Eq. Pull down some of the sliders around 3000 like I did in the illustration and [OK] apply it. 3000 is the rubbing screaming babies on a blackboard frequency. Does it sound better? Edit > UNDO equalization and run it again with different sliders until you get a combination you like.

Screen shot 2014-07-06 at 4.16.00 PM.png

Audacity doesn’t do real time processing, so you’re stuck with successive approximation.