mp3 and cd

[vanillavato]

<font color='#000000'>If you had some music like pink floyd to kind of test your system, would it make a difference if it was a real copy or a burnt one? Like normal MP3's seem to be 128 but does any one know what the quality of a real cd is?</font>

 

[Guest]

<font color='#000000'>Hi Vanillavato,

Audio CD's are recorded with a bit depth of 16-bits, and a sampling rate of 44,100 samples per second.  That's four bytes per stereo sample, times 44,100 samples per second, or 176,400 bytes per second (that's 172 kbps in computer lingo, or 176 kbps in any other field).

MP3 audio uses data compression to reduce the digital bandwith.  Since it is a lossy compression, it can have audible side effects.  Critical factors include the compression ratio selected (128k is better than 64k, for example), and the material being compressed.  I have yet to see an MP3 compressor that could do a credable job with recordings of Harpsichord music (as just one example of where MP3 can get into trouble).

Personally, I would not use MP3 files to evaluate equipment.  On the other hand, I don't use MP3 for much of anything.  If your primary goal is to listen to MP3 files, then it just might make sense to evaluate gear using the same kind of material you plan to listen to most of the time.

If you want the most from MP3, try to find an encoder that handles VBR (variable bit-rate) encoding.  Depending on the encoder, this can be an improvement over fixed data-rate compression.

My advice would be to audition gear with the same kind of material you expect to listen to most of the time once you get the gear home.

Hope this helps,

Chuck</font>

 

[Guest]

<font color='#000000'>Alright that sounds good. Thanks Chuck.

</font>

 

[vanillavato]

<font color='#000000'>One more thing, is 128 kpbs to 160 that much of a difference and those 2 compared too a real audio cd? Are audio cds worth buying compared to mp3 quality?</font>

 

[Guest]

<font color='#000000'>Whether you hear a difference when you change the data rate will depend in part on the kind of musical material being compressed, and the kind of system it is reproduced on.  Same thing applies to whether or not you'll hear a difference between a CD and an MP3 file ripped from the CD.  As to whether or not the better sound justifies the cost of the CD, that's something you'll have to decide for yourself.  As I said before, I don't use MP3 for much of anything, because I want the highest quality i can find.  The few MP3 recordings that I do keep around are performances that I can't get on CD, and they were only available as MP3 files.  Others find that the MP3 format is sufficient to meet most if not all of their listening needs.  To decide whether or not it's worth it for you personally, you might try comparing compressed and uncompressed files on a number of recordings.  Rip the files to your hard drive as a 44/16 .wav file, then create an MP3 copy using your compressor of choice.  Then play them both and see if you can hear any differences, and if the differences you do hear bother you.  Try a range of recordings, because it will make a difference.  As I said earlier, I have yet to hear a recording of a harpsichord that sounded right after MP3 compression.

Do a little experimentation on your PC, and decide for yourself.  Sorry, but that's the best advice I can give you on the value of higher quality audio.  To me, it's worth whatever it cost.  ;-)

Hope this helps,

Chuck</font>