Human hearing and standard CD Vs. SACD / DVD-A

I am sorry, but I must disagree with you on this. MP3 at whatever KBPS is nowhere near a Redbook CD, let alone a DVD-A or an audio CD. I have heard clearly audible differences and lack of depth in an MP3 version of the same musical number as compared to a simple Redbook CD. Please understand that to covert a 40 MB to something like 4 MB, you are losing a lot of data irrespective of whatever compression techniques you use. That is the reason, MP3 is called 'lossy' compression.

Please take a look at Stereophile: MP3 vs AAC vs FLAC vs CD where John Atkinson has very clearly proved that MP3 is not good. I have personally listened to both a MP3 version and a Apple lossless (AIF) version of a song that I ripped myself. On the same audio equipment and on a brand new Classic iPod with good earphones. the difference was like day and night.

John concludes in the article as follows.

QUOTE
Basically, if you want true CD quality from the files on your iPod or music server, you must use WAV or AIF encoding or FLAC, ALC, or WMA Lossless. Both MP3 and AAC introduce fairly large changes in the measured spectra, even at the highest rate of 320kbps. There seems little point in spending large sums of money on superbly specified audio equipment if you are going to play sonically compromised, lossy-compressed music on.
UNQUOTE

I am not a great admirer of Stereophile or John Atkinson. But this is one point I will wholeheartedly agree with him.

Cheers

Ms. Shanthi:

I have a Oppo 983 that plays SACD and a DVD-A. This is connected to an Onkyo 875 that can understand and decode LPCM data.

I have listened to a number of DVD-A such as Dhoom 2, Vettayadu Villayadu, and Wagners Overtures Preludes, played by Berliner Philharmoniker conducted by the great Herbert Von Karajan. The Wagner, in particular, was mastered from the original analogue tapes by Abbey Studios, and is a masterpiece. The Dhoom 2 and Vettayadu Vilayadu were also recorded at 24bit/48Khz from mult channel original analogue tapes and sound excellent when heard.

DVD-A envelops you in a way that a Redbook CD can never do. It is a different feeling altogether and has great effect in music that has multiple instruments and singers.

In a Redbook CD called "Ragamala' by Ravi Shankar who plays the Sitar alongwith the Royal Philharmonic conducted by Zubin Mehta - there is a number that I just love. In this number, an artist takes a small bell that he plays in tune with the number and 'walks' across the stage. If you close your eyes, you can actually visualise the bell moving from one end of the stage to another. I would any day pay a premium if I can get a SACD or DVD-A of this great album.

Cheers.

Srinath opened this thread with a article hea read somewhere. By a strange coincidence, I came across an article by John Atkinson of Stereophile written in 1995 on the same subject. This sounds like a lesson in History.

QUOTE

Perfect Sound Forever?

By John Atkinson • May, 1995

When some unknown copywriter coined that immortal phrase to promote the worldwide launch of Compact Disc in late 1982, little did he or she foresee how quickly it would become a term of ridicule. Yes, early CDs and players offered low background noise, a flat spectral balance, and freedom from wow and flutter. But all too often, the music encoded in the "perfect-sounding" pits seemed to have taken a vacation, leading the renowned recording engineer John Eargle to offer, in the medium's defense, that if you were to hear just one CD that sounded good, digital technology would be proved to be okay.

While we waited for that exception to truly prove the rule, we found that neither was the word "forever" a guarantee. I remember one radio station proudly proclaiming its allegiance to the future by promising to play CDs exclusively, only to have its very first broadcast marred by a skipping CD.

But even as "perfect sound" and "forever" were being recognized as marketing hype, the problems with both the CD medium and with digital recording were starting to be addressed. It was known even before the CD launch in 1983 that professional digital recorders needed word lengths longer than 16 bits if there was any chance that the data on the CD would have anything approaching true 16-bit resolution. Dreadful digital editors were replaced by transparent hard-disk systems. The performance of analog/digital converters took a quantum leap forward in late 1988 with the introduction of the Robert Adams-designed 20-bit UltraAnalog ADC module. The realization that datastream jitter could significantly reduce signal resolution took rather longer to develop; but coupled with the introduction of quieter, more-linear DAC chips and high-resolution digital filters, this enabled even inexpensive playback systems to achieve true 16-bit resolution in the mid-'90s.

However, even as that was happening, engineers started to realize that significantly better sound quality could be achieved with digital word lengths longer than 16 (see the January 1994 "As We See It"). Mastering techniques and processors such as Sony's Super Bit Mapping, Apogee's UV-22, DG's 4D, and Meridian's 618 the latter used on Concert all preserve a significant amount of 20-bit sound quality on the 16-bit CD. And now we have the commercial availability of High Definition Compatible Digital CD (see our interview with its inventors in this issue), which uses a buried subchannel to take 16-bit replay to a new level of sonic performance at least in the opinions of Robert Harley and myself.

Yet so far, the overall reaction to HDCD has been mixed. Putting aside commercial questions regarding Pacific Microsonics' licensing policy and the fact that only one record company, Reference Recordings, is currently releasing HDCD-encoded CDs, not all who have heard decoded HDCD think it offers significantly improved sound quality. This puzzles me, as I feel HDCD's opening up of the reproduced soundstage and its clearer presentation of recorded detail are reminiscent of what I have heard from true 20-bit digital media. But some denizens of cyberspace have found decoded HDCD recordings to sound merely different rather than better, leading me to muse that if we actually heard perfect sound quality, would we even recognize it for what it was?

The answer to that question will become clearer once more record companies release HDCD-encoded CDs and as more D/A-processor manufacturers incorporate the Pacific Microsonics digital filter chip. I wonder, however, if a more serious criticism of HDCD is that it might be too late. As you will have read in April's "Industry Update" (pp.331-37), the 16-bit CD itself could be superseded. Both Toshiba and Sony/Philips have announced CD-sized media two different "Digital Video Discs" that can carry between four and twelve times as much data as a CD. Although this new technology is aimed at the video market, many see its potential for carrying a music signal encoded with up to 24-bit data words or with a higher sampling rate either of which might render moot the need for HDCD.

Don't throw your CD and laserdisc players in the trash just yet. HDCD offers a real jump forward in sound quality right now, and I don't think a high-density CD medium whichever of the two wins out will be a commercial reality much before early 1997.

But I am excited about the potential for the true coming-together of video and audio offered by DVD. I envision a common-carrier future in which a header on every 5", high-density disc tells a universal decoder what it is: an MPEG-2-encoded movie with a Dolby AC-3-encoded, 5.1-channel soundtrack; or a movie with a DTS Zeta-encoded six-channel soundtrack; or a movie with three different-language, Dolby Pro Logic stereo soundtracks; a 24-bit stereo music recording; a 16-bit, 44.1kHz-sampled, HDCD-encoded, six-channel music recording; a 20-bit, 88kHz-sampled, Ambisonics-encoded surround-sound recording; and so on. All the signal processing would be handled by a versatile DSP engine, the player automatically adjusting the playback decoding algorithm video and/or audio to whatever was appropriate.

And if a new recording technology was introduced, the owner would simply upgrade her player's software. Or, more likely, the disc itself would contain the new instructions for the decoding DSP much as Dolby Stereo Digital films include the AC-3 decoder software in the data area before the movie starts. (The cinema's system automatically updates itself if it detects a more recent software version on the film.)

As with all future-gazing, I'm probably more wrong than right. But one high-density medium for many high-quality formats that's an idea that excites me even more than the introduction of HDCD.

UNQUOTE

I am sure John must be chuckling to himself.