Noticeable hiss or hum or distortion -- Cassette quality.
A digital recording of a live event. An accurate representation of what the audience heard, but probably not what the performers wish the audience had heard.
A studio recording with some barely noticeable flaws such as background traffic noise.
A virtually perfect studio recording.
Many glaring problems such as singing out of tune, rhythmically not together, etc.
Occasional glaring problems as above.
Definitely amateur, with many subtle problems.
Occasional and barely noticeable performance errors.
Professional in all regards.