Adobe Audition improving audio quality

[AlexRub]

Hello! I have a recording with sound quality that I would like to improve. Got Adobe Audition software and tried various things in there (mainly different Effects). However, I'm not a professional and whatever I do does not make much of a difference. The software is clearly designed for professionals (too many parameters to change). Thus, I'm seeking some professional advice. Here is the excerpt of the audio which should also be available in this message (it's my first post and I don't know if the file is attached properly). I would really appreciate it if someone could provide some advice on how to improve the quality of the audio (if it is possible). Thank you very much in advance!

[SteveG_AudioMasters_]

You can never 'improve' the basic quality of the audio you record (or indeed that anybody records) - that's inherently as good as it gets. Things like distortion and anything that's missing simply can't be fixed. You can get rid of extraneous sounds, and reduce background noise, and even EQ things, but that won't alter the basic quality - which is entirely down to the way you capture the sound and store it. For instance, if you store your recording only as an MP3 that's an instant quality loss that you can't get back - you need to store your original recordings as uncompressed wave files, not compressed MP3. Applying any form of effect randomly is inevitably going to make things worse, not better, I'm afraid.

[AlexRub]

Dear Steve! Thank you very much for your quick reply! Just to make sure: the hollow sound (talking like in a tube), hissing "s", etc. cannot be eliminated, right? Thank you again!

[AlexRub]

In addition to my previous reply: I forgot to mention that the original file (not the excerpt) is in M4A format. Can any improvement be done in that case? Once again, thank you!

[SteveG_AudioMasters_]

M4A is still a compressed format - but that makes no difference, really, as it's generally not as bad as MP3. But there is no getting away from the fact that the ultimate quality of a recording depends entirely upon how it's captured in the first place. That's why we have to use carefully treated recording spaces, and use relatively expensive mics if we want a good result.