The Source CD and SACD

High end sound reproduction starts with good source material

The last two decades the quality of source material has improved enormously. For home audio music, the record has been replaced by the high quality of the CD. Currently a new standard is being set by Sony and Philips. Both companies are the inventors of the so called Super Audio CD (SACD). SACD is meant to replace the older CD standard. SACD has even higher performance than CD. For every audiophile it is important to invest in good CD players to get out of what is in the original recording. However, the source material often lacks a good recording and high end music perception is compromised.

CD and the new SACD standard

Since the introduction of the CD standard in the 80s, the quality of audiophile sound reproduction has been improved tremendously. Also in the high end area CD truly sets the standard for listening music. From CD it is long known that good professional analog recording performed better in frequency domain (~50kHz) and dynamic range (>110dB). SACD claims to overcome these shortcomings and can truly be competitive with professional analog recordings.  

CD versus SACD

I am not convinced about the commericial success of SACD and so about a long existence of SACD. In fact, I believe MP3 might set the new standard for consumer source material (not for master recordings). Despite the said low quality of MP3, the record industry will follow the biggest commercial success and SACD might end in the background.
For audiophiles, SACD is an improvement and these people will buy SACD anyway, but the large mass of people is satisfied with the quality of MP3. They probably don't even hear the difference between MP3 and SACD. Besides, MP3 music compression makes use of the knowledge that can be found in psychoacoustics. Understandig this theory, MP3 does not need to be so bad when the correct compression algorithms are used.

SACD also features multichannel sound in soem cases. Although nice, the large mass of people only want multichannel for watching movies and that's already on DVD. Besides, for movie theatre you don't need a very high quality sound system. The multi-channel SACD can be advantageous for a real live audiophile sound experience unless properly recorded. And that last thing is the pain. My experience is, that these additional channels are may times used for a "ping-pong" sound and not for creating spatial sound. Compare with the quadrophonic years, it has never become a real success. Then, most likely, SACD is for high quality stereo sound and I doubt the commercial success of that. It would be a pity.

How does SACD sound?

Characteristic about SACD compared to CD is, that the sound is absolutely more natural. This is clearly noticed for speech/vocals. The voices are more airy and fills the room. It is less "thin" and much more realistic. If you think that your speakers sounded great with CD with the openness for vocals than you should have SACD. It's even more open and really gets loose of your speakers. The multichannel feature is impressive for getting more spatial sound if you have a good recording. Nonetheless, it is expected that high end will remain in the  two channel music reproduction since the multichannel is often wearying.

From audiology it is known that speech/vocals are the most complex sounds that the human hearing can process. And especially for vocals, SACD proves its value. From an audiological point of view, I believe that the good sound quality of SACD comes majorily from the improved 110dB dynamic range (CD =95dB). The human hearing has a dynamic range of at least 110-120 dB (normal hearing). This means that SACD has reached the limits of normal hearing concerning dynamic range whereas CD is smaller. The increased dynamics change the perception of amplitude, say timbre and this is noticed for voices becoming "richer" and more natural.
The improved frequency range can affect the pitch of the sound but is most probably not a decisive factor. For CD, 20kHz was already available. SACD goes up to 40kHz. The pitch of normal hearing is limited to frequencies up to 16 kHz. SACD can change pitch with the higher harmonics from the source material. But even for the higher harmonics CD already or at least is very close to the limits of human hearing. Nevertheless, the pitch of the highest frequencies can be improved with SACD which can, in turn, make voices and instruments sound more natural.

How about the quality of SACD recordings?

It must be noticed that the quality of currently available CDs is often compromised. Although the CD standard makes it possible to have a dynamic range of 95 dB and a frequency range of 20-20kHz, most CDs (and especially the popular CDs) do not have more dynamics than 70-80dB. Also, recording of the highest frequencies are limited. It is very dissapointing to see (or better: hear) that source material is often quickly recorded in studios under pressure of time. Often, little attention is paid to good recording and mixing of instruments and vocals.

What to think of SACD when it is becoming a commerical success and it replaces the normal CD? Most probably the source material will not become better in the studios and, as a result, SACD recordings will have a dynamic range of 70-80 dB, poor mixing results and frequencies limited to about 20kHz. This would cause the SACD not to be better than the normal CD.
The small amount of SACDs currently available are recorded with great care and as such do have a large dynamic range. Indeed, they are better sounding than CD. But I fear that the capacities of SACD will not be fully used in the future.  


More on this Topic

speaker

Psychoacoustics determines to a large extend how we perceive sound and music. 
More on psychoacoustics ...

VFD display
The filters and amplifiers are controlled by an MCU.
More on amplifiers ...

Also in this section