Many different people do 'Mastering',. and each one does it in his or her own special way that they want to convince you is better than everyone else's. The main steps in mastering are eq, compression, and level matching. Very few cd's are printed with clipped samples, because this data is out of range, it can't be reproduced, if the playback of the cd results in a clipped waveform it could be either a perfectly recorded clip or it is a failure of your hardware to faithfully repoduce the waveform as it is encoded on the disc. Most generally it is the latter.
When finished tracks are sent to be 'Mastered', they are usually compressed a little bit, or a lot, depending on the taste of the Mastering Engineer. Compression in this case doesn't refer to encoding audio in a compressed format, rather a compressor is a dynamics processor, with it you can set a threshold above which the sound will be modified based on a ratio like 2 or 3 to 1. So for a 2 to 1 ratio any sound that is above the threshold will be reduced by half.
This was initially done back in the old days when you had at best 45 dB of dynamic range to work with on your recording medium, a very noticable noise floor, and material with a dynamic range of 120 dB (Live Rock). Obviously you can't stuff 120 dB into a 45 dB (cassette tape(if you are lucky)) dynamic range, So the material was compressed to fit within the dynamic range. Also because of the quality(lack thereof) of consumer audio equipment and the previously mentioned very noticable noise floor, most music is compressed into the top 3-5 dB of whatever medium it is recorded on.
Nowadays, we have a playback medium with a 96 dB dynamic range and close to a 96 dB noise floor, but because people got used to the way it used to sound, they want to keep hearing it that way. Pretty much the only recorded materials that truly benefited from the increase in dynamic range allowed by CD's and digital recording are orchestral works, and the people that listen to these avidly, and care about the recording truly reflecting the performance, still want more!
The other aspects of 'Mastering' are a great deal more subtle, equalization and level matching between tracks are things that most people do not notice unless it is done badly. At the end they turn the result up to the top of the mediums allowable dynamic range and start printing tens of thousands of them at a few cents apiece.
If you think a cd has clipped samples recorded on it the best way to check is to rip the track off the disc into a PCM (Non Lossy, Non compressed, Non MP3)format at 16 bit/44.1 (Redbook native format) and look at the samples in question with a wav editor. If you have blown up the waveform to the point where you can see a single sample, and the tops of the waveform are at the cieling and flat, then complain to the recording engineer, because it is probably his fault.
BTW make sure it is a clean non scratched cd, any unrecoverable data loss can appear as a clipped waveform, and is heard as such depending on the smoothing filter on the output side of your cd player.
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Many different people do 'Mastering',. and each one does it in his or her own special way that they want to convince you is better than everyone else's. The main steps in mastering are eq, compression, and level matching. Very few cd's are printed with clipped samples, because this data is out of range, it can't be reproduced, if the playback of the cd results in a clipped waveform it could be either a perfectly recorded clip or it is a failure of your hardware to faithfully repoduce the waveform as it is encoded on the disc. Most generally it is the latter.
When finished tracks are sent to be 'Mastered', they are usually compressed a little bit, or a lot, depending on the taste of the Mastering Engineer. Compression in this case doesn't refer to encoding audio in a compressed format, rather a compressor is a dynamics processor, with it you can set a threshold above which the sound will be modified based on a ratio like 2 or 3 to 1. So for a 2 to 1 ratio any sound that is above the threshold will be reduced by half.
This was initially done back in the old days when you had at best 45 dB of dynamic range to work with on your recording medium, a very noticable noise floor, and material with a dynamic range of 120 dB (Live Rock). Obviously you can't stuff 120 dB into a 45 dB (cassette tape(if you are lucky)) dynamic range, So the material was compressed to fit within the dynamic range. Also because of the quality(lack thereof) of consumer audio equipment and the previously mentioned very noticable noise floor, most music is compressed into the top 3-5 dB of whatever medium it is recorded on.
Nowadays, we have a playback medium with a 96 dB dynamic range and close to a 96 dB noise floor, but because people got used to the way it used to sound, they want to keep hearing it that way. Pretty much the only recorded materials that truly benefited from the increase in dynamic range allowed by CD's and digital recording are orchestral works, and the people that listen to these avidly, and care about the recording truly reflecting the performance, still want more!
The other aspects of 'Mastering' are a great deal more subtle, equalization and level matching between tracks are things that most people do not notice unless it is done badly. At the end they turn the result up to the top of the mediums allowable dynamic range and start printing tens of thousands of them at a few cents apiece.
If you think a cd has clipped samples recorded on it the best way to check is to rip the track off the disc into a PCM (Non Lossy, Non compressed, Non MP3)format at 16 bit/44.1 (Redbook native format) and look at the samples in question with a wav editor. If you have blown up the waveform to the point where you can see a single sample, and the tops of the waveform are at the cieling and flat, then complain to the recording engineer, because it is probably his fault.
BTW make sure it is a clean non scratched cd, any unrecoverable data loss can appear as a clipped waveform, and is heard as such depending on the smoothing filter on the output side of your cd player.