Saturday, January 5, 2013

The Beatles Remastered

I often start things I don’t finish. I’ve written almost 200 articles (or themes or monographs or whatever) in my blog. Included in those writings are several “series” I’ve started, but have not finished. I was writing about recording studios and physics topics that were intended to include several episodes, yet I’ve only completed one or two. I wrote a dozen articles about the science of photography, but there are more to come. I also wrote a lot of pieces on music and science, and there are more planned for that too.

In the latter case, I was working toward an explanation of why digital really isn’t as good as analog recordings. You know, CDs vs LPs. I started by describing just what music recordings are made of: sine waves and Fourier Analysis. From there I wrote on noise and frequency response and psycho-acoustic effects. But there is more to come.

Yes, it is true that albums are better. I intended to describe this scientifically and technically, specifically for a good friend of my in Montana that is very, very into albums … and the Beatles.

I haven’t completed that series yet, but I recently ran across some information on the Beatles that just forced my hand. Hence, this short article.

The Beatles recorded between 1963 and 1970. At that time all recording was done on analog tape that were turned into records or albums. That was all that was available for the Beatle’s fans until 1986. Eighty-six was the year that the entire Beatles catalog was digitally remastered and turned into CDs. That was only four years after the CD was first introduced, and these CDs were not very good, even for the state-of-the-art at that time.

There are two specifications that matter in digital recording. The first is called “bit-depth” or number of bits. This value determines the dynamic range of the digital recording. Dynamic range is the amplitude or “volume” capability. The range from softest to loudest music recorded. The more bits, the larger the number of discrete amplitude values that can be recorded and played. More bits is better.

The second is the sample frequency. That’s how often per second the analog values are sampled or turned into bits. I won’t get into the details now, but save that for my longer article that will be added to the “Science of Music.” In that more detailed writing I’ll explain Nyquist’s Theorem and a lot more. Basically the sample frequency must be twice the highest frequency to be captured.

Although it depends on things such as the quality of the playback system and the age of the listener (younger people can hear higher frequencies than oldies … old people that is), digital frequency response depends on sample frequency. We assume that a frequency response at the high end of 20KHz is pretty high fidelity. Standard CDs can reproduce frequencies up to 22 KHz.

The technical specifications for CDs and CD players are given in something called the “Red Book.” All CD producers and manufacturers of CD players follow these technical instructions. That assures compatibility, so a CD can be played on any standard player.

The first edition of the Red Book was released in 1980 by Philips and Sony; it was adopted by the Digital Audio Disc Committee and ratified as IEC (International Electrotechnical Commission) 60908 (published in 1987). This standard set the bit depth at two-channels of 16-bits and a sample rate of 44,100 Hz. This sets the maximum frequency response at 22.05 KHz, but yields a very limited dynamic range.

The common Waveform Audio File Format (WAVE, or more typically known as “.wav” due to its filename extension), is a Microsoft and IBM audio file format standard for storing an audio bit stream on Personal Computers. The format of a .wav file matches a CD’s 16-bit/44.1 KHz sample rate.

When I record in my studio, I typically use a bit depth of 32 bits, but that is more to eliminate “rounding errors” when I use digital effects. The bit rate is always down-converted to 16-bit when I burn a CD. (You’ll hear more about down-conversion as you read on.)

A recent, new production of Beatles material in the album “Love,” created by the original Fab Four Producer, George Martin, and his son Giles for Cirque du Soleil in 2006 brought me hope. I knew that the Martins had digitized from original analog tapes in their production of the mash-up Beatles work … a work that I found very interesting and new, in an old-fashioned sort of way. So I was expecting to “hear” more about the Beatles collection.

Most Beatles music collections today consist of the original CDs that sold very well all through the 80’s and 90’s and right up to 2009. In ’09 the catalog was remastered again. This time high-resolution 24-bit/192 KHz standards were used.

That is wonderful. However the high-resolution digital versions of the albums remain safely in the vaults. Down-converted versions were used to master the standard 16-bit/44.1Khz CDs in 2009. (Down conversion is the digital process of reducing both dynamic range and frequency response.)

In 2009, these new digital versions were used to master 14 new LPs on thick 180-gram, audiophile quality vinyl. The down-converted versions were used to master new 16-bit/44.1KHz CDs. Fortunately, the 24-bit/192 KHz masters were used to produce the new LPs.
The music publishers and their engineers claim the analog masters are too fragile to withstand the rigors of mastering, but why go with the dumbed-down CD masters?
You might be asking, “No matter what specs the masters follow, don’t they have to be “dumbed down” to put on a CD?” The answer is, “Yes.” BUT, they could be put on DVDs with 24-bit depth and 192 KHz sample rate. High quality audio is more common on DVD movies, but you can get DVDs of music. 
DVDs also supports "surround sound" recordings such as Dolby 5.1 or 7.1, but back in the '60s, the Beatles primarily produced mono recordings. They did make stereo versions too, but left the engineering of the stereo recording to their ... wait for it ... engineers. The great music producers of the 60s from the Beatles to Brian Wilson produced mono mixes and left the stereo to the technical people. Phil Spector wouldn't even do stereo versions. He thought mono was the purest sound. So don't expect to see authentic surround sound recordings of these classical rock products.
They could also be used for download on services such as iTunes and Amazon, but downloaded music tends to be even lower fidelity than standard CDs. Typical downloaded music is in some compressed format such as AAC or MP3 which are even lower fidelity than a .wav file.

Whatever the engineering and math, it is good news. New versions of Beatles LPs,  "Rubber Soul," "White Album," "Abbey Road," and others.

There are differences with the new LPs.  It is reported that they're a little warmer, but the new pressings have more surface noise than the earlier pressings. Apparently there are some quality-control issues with the new LPs.

Amazon sells the new albums for $249.90 each in a boxed set, and I don't think the new records justify the premium pricing. I recommend searching out the old all-analog British pressings. But I don’t have to tell my friend Ron that.

No comments:

Post a Comment