The quality of music or audio in individual CDs will differ. It will be very difficult, for example, to get good CDs of old films songs as the original tape itself would have scratch noises. At the same time, I have over 200 CDs of both Hindi and Tamil film songs. These have been remastered by companies such as HMV/RPG. I have heard these on systems costing 100,000$ and more and cannot find any fault. When I go for audition I usually carry a wide variety - hindi/tamil film songs, Ravi Shankar's Concerto for Sitar and Orchestra, a Veena/Saxophone, a Fusion (Rhythm House), Breathless by Shankar Mahadevan, an orchestral number (Beethoven/Mozart), and a Japanese Album. I have used Breathless so many times, I ended up buying 3 or 4 copies. Most systems would fail to play Latha's old songs well as her pitch in many songs is very high. This is not a problem with the CD as much as it is a problem with the fact that there are very high frequencies in these songs. If you play a Mukesh or a Rafi on the same system, they would sound heavenly.
RPG had released a set of 65 odd CDs called 'Classics Revival' that has excellent songs from 1950s to the 1970s. They have take extraordinary pains to cut each CD properly. I have all the CDs, excepting a few Unfortunately these are not available now. I am ordering what I don't have as individual songs and completing the set.
I the recent past, the music of some films are being released as DVD-Audio with superb 5.1 sound. Some example as Vetayadu Vilayadu in Tamil, and Dhoom in Hindi.
I have heard a lot of people say that all Indian CD and DVDs are of poor quality. This has made my hair stand on end. For the last 15 days I have been working on the Net and talking to music directors, film directors, music companies to find out what they are doing. The results are very interesting. Please wait for my posting. hopefully I will have it up by middle of next week.