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Jun 102014
 
My lovely old Garrard 401 turntable, SME 3009 tone arm and Shure V15 cartridge.  Is this 50 year old technology the zenith of music reproduction?

My lovely old Garrard 401 turntable, SME 3009 tone arm and Shure V15 cartridge. Is this 50-year-old technology the zenith of music reproduction?

This is the first part of a new series on digital music.  Part two is here, stay tuned for more.

There’s an interesting contradiction when we consider trends in listening to music compared to watching video.  Video quality has massively improved but audio quality has got appreciably worse.

With video, just think about the enormous improvements in picture (and sound) quality that have occurred over the last few decades.  We’ve gone from black and white television screens that were as much circular as rectangular to enormous wall sized wide-screen color behemoths, and what was formerly thought to be wonderful quality video at 220 line resolution (ie VHS) has gone to laser (330 line), DVD (480 line) and on to Blu-ray and HDTV (1080 line) and now up to 4K resolution (2160 line) with hints of continued improvement in the future (anyone for 8K?).

Video has improved almost 100 fold in quality, and has done this not only via recorded physical media (ie Blu-ray disc) but also via internet streaming as well.

But what about audio?  The original audio recording technologies (primitive wax cylinders) evolved into 78 rpm records which in turn started to be supplanted by 33 1/3 rpm (so-called ‘long play’ or LP) records in 1948.  Stereo sound appeared ten years later, and a series of incremental improvements in both recording and playback technology followed over the next couple of decades.

The Rise of Digital Audio – the CD

An apparently enormous enhancement occurred in the early 1980s with the release of compact discs.

They had several major and obvious advantages over LP records.  They had a much greater dynamic range between the quietest and loudest passages recorded, they had much better stereo separation, and they could hold almost 2.5 times as much music on one side, while being much smaller in size.  Best of all, they lasted almost for ever, and seldom/never suffering from the annoying scratches and wear/distortion that unavoidably developed on LP records.

CDs store sound in digital rather than analog format, with a sampling rate of 44.1 kHz and a sample size of 16 bits.

These obvious advantages more than outweighed any detailed consideration of the ‘best case’ sound quality of the analog LP compared to the digital CD – while the man in the street could understand ‘plays 75 minutes without stopping’ and ‘almost impossible to scratch or wear out’, who could really understand the implications of sample rate and depth?

(Note this ultra-brief history ignores tape and various other formats that never became universal – in general, consumer tape devices were never as good as LP and CD products, and as for all the other failed products – 8 track cartridges, Minidiscs, and so on, because who really cares.)

Was the CD an Improvement over LP Quality?

In years subsequently, some people have suggested that the CD sound quality is actually not much better and maybe even slightly inferior to LP sound quality – here’s a 2013 article, for example, that makes this suggestion.

We find such commentary unpersuasive, and suspect it is similar to people who advocate spending ridiculous amounts of money on ‘ultra quality’ cabling.  In particular, the weakness we see is that the people who talk about the better quality of analog rather than digital sound generally ignore the fact that much of the sound processing between the microphone and the ultimate CD or LP is done digitally.  Pure analog audio is very rare these days, making the argument about analog vs digital rather moot.

But we will concede that CDs did not greatly advance the underlying audio quality, and their original specification could well be revised and upgraded to a faster sampling rate and greater sample depth.  Unfortunately, although there have been various attempts to introduce new enhanced digital music formats (increasing 16 bits up to 24, and the sample rate from 44.1 kHz to 48 or even 96 kHz), none have gained any market traction or acceptance, and the CD format remains the ‘best’ there is for almost all music.

The Big Backward Step – MP3

Now for the interesting part.  After the leap forward presented by the CD, which first appeared in the very early 1980s – almost 35 years ago, back when standard VHS was battling it out with Betamax for video format supremacy – what has happened since then?  Video quality has improved something like 100-fold, and indeed, the audio portion of a movie has gone from poor quality mono to now sometimes dazzling quality eight channel (ie 7.1) surround sound.

For audio, the next ‘big thing’ in audio formats was the advent of the MP3 format and the new portable music players – a field quickly taken over and dominated by the iPod.  But, whereas a CD has a data bit rate of 1.4 Mbits/sec, MP3 music typically has a data bit rate in the order of 64kb – 256kb/sec.

Now, be careful in comparing these numbers.  MP3 format music is compressed, so in theory there is ‘more music information/quality’ per unit of data in an MP3 than in a CD.  But, the other side of that coin is that MP3 format music is what is called a ‘lossy’ compression format.  It ‘cheats’ and takes some shortcuts in compressing and then re-expanding the music it stores, a bit like a jpg image, which also uses a lossy rather than lossless compression technique.  It is hard to describe differences in sound quality without sounding pretentious like a snobby wine reviewer, and so a picture analogy is helpful.

An image with only slight jpg compression and still highly detailed.

An image with only slight jpg compression and still acceptably detailed.

 

An image with much more jpg compression and perceptible loss of picture detail.

An image with much more jpg compression and now perceptible softening and loss of picture detail.

As you can see with the jpg examples above, the difference in quality is subtle rather than substantial, but if you know what to listen for and hear, you will start to notice the results of lossy audio compression.  In particular, you’ll perceive a loss of quality in louder passages, and a fuzzy lack of sharpness in quiet passages.

You’ll see a loss of sharpness and fine detail in the picture texture in the more compressed picture above, and the same is true with lossy audio compression.  For example, with uncompressed audio, you can hear the sound of the bow being drawn across a string on a violin, and can sense the slight raspiness of it, but when played in MP3 format, it sounds smoother.  You can hear the whisper/breath of a woodwind instrument as well as the tone of the notes the player produces, but in MP3, you just hear the sound and not the underlying additional detail.

In percussion music – for example, a piano (which is one of the hardest instruments to record/playback) – you can hear the ‘attack’ of the hammers hitting the strings as well as the sounds they create.  And in loud crescendos, if you turn the volume down when playing it back, you can clearly hear the different instruments in the ensemble all contributing to the totality of the sound, whereas if you turn the volume down on a loud bit of an MP3, you realize there’s just a mush/mess of almost static with some detail on the top but nothing underneath.

Some of these issues may not matter so much with some forms of music – in some types of more modern music, distortion is deliberately introduced for effect anyway, and people don’t seek to listen to it for an exact replication of a live performance but rather simply want to have a general background experience to distract them.  If you’re listening to music in a noisy environment, or through low quality equipment, then the quality loss is again insignificant.

But for an audio purist who seeks to enjoy not just the musical piece itself but the sound quality of its performance too, MP3 compressed music is a backward step.

To use a possibly unfair analogy, some people drink whisky as a social experience and perhaps to get drunk.  Other people sip single malts so as to savor the taste sensation.  If your approach to music is akin to savoring your single malts, you’ll be disappointed by MP3 format music.

Whether it matters to you or not, the ‘evolution’ of music storage from CD to MP3 format saw sound quality decline rather than improve.

Digital Downloads Displace CDs

CDs are no longer the dominant way of storing and distributing music.  Unfortunately, the successor to CDs is massively inferior rather than an improvement – which is probably the first and only time that a new technology, displacing an older technology, has been worse rather than better.

Digital downloads, and more recently, digital streaming of music, arguably offers you convenience, and possibly offers you some value benefits too, but in return for these benefits, you are required to sacrifice quality.

A No-Longer Necessary – But Still Common – Compromise

It is true there were arguably valid reasons for the quality compromises inherent when the MP3 format first started to become popular (the first iPod was released in 2001).  Back then, internet speeds were much slower, and hard disk capacity much smaller (and more expensive) than it is today.

But in the intervening almost 15 years since MP3 technology first came out, what has happened?  Typical internet speeds are at least twenty times faster, and data storage prices are at least twenty times lower.

But sampling rates have only slightly increased, usually by less than double.  It is now common to find sampling rates of 128kb – 256kb, but even at the maximum sample rate the format can handle (320 kb/sec, a bit less than one-quarter the sample rate of a CD) the sound quality is still poorer than on an old-fashioned CD or an even older fashioned LP.

Of course, it has always been possible to simply copy the digital data on a CD onto your computer, or possibly onto a portable music player, and then play that directly, with no loss of quality.  But that sees each hour of music consuming about 630 MB of space, which limits the amount of music you can have.  That would mean a 16GB iPod could store about 25 hours of ‘pure CD’ music, compared to almost 140 hours of MP3 at a 256kb sample rate.  Most people felt (and still feel) the trade-off in music quality was acceptable in return for the much greater song storage capacity per GB of capacity.

Strangely, music streaming services have also stayed with low bit-rate streaming.  Indeed, if you look at ‘internet radio’ stations, you’ll see some offering streaming rates as low as 64 kb/sec, and it is very rare to find any over 128 kb.  Yes, if you go to Netflix and watch a high quality video, you might have the data streaming at 5 Mbit/sec, but if you go to an internet music service, your audio stream will be maybe only 128 kb/sec – and probably less than the sound portion of the Netflix movie stream!

Music and its quality has become the overlooked orphan of the digital era.  One can only guess as to why this is, but no-one can dispute the reality of the situation.

But now, after all of this, it is time for some good news.

A New Way to Enjoy High Quality Portable Digital Music

We are not limited only to MP3 type music storage.  Indeed, we never have been, but the arguments formerly favoring MP3 are no longer as relevant as they were ten and twenty years ago.  There are better ways to store music that give a better compromise between storage space requirements and sound quality.  Particularly now that storage is much less limiting – either in terms of capacity or cost – there is less need to compromise in quality.

There are a number of music formats that store CD quality music in a compressed format, but without any quality loss when the music is compressed and then expanded back to its original form.  Perhaps the best of these formats is called FLAC, and it can reduce the size of a CD by about 50%, with no loss of sound quality at all.  This is the best possible way to store and play back your music.

If you are an audiophile, then your best approach to storing music these days is probably to buy CDs, which most of the time remain the highest quality source material we can obtain, then to convert (ie ‘rip’) them to FLAC format, copy them to an appropriate portable music player (Apple’s iPods do not support FLAC format, although most Android devices do), and play back through high quality headphones (not the disgusting little ‘ear bud’ things that one sees everywhere) or a decent hi-fi sound system.

There’s a certain irony in that we’ve ended up with something remarkably equivalent to the technology obsoleted by MP3 players.  Remember ‘Walkman’ type portable CD players?  This new technology ends up with a similar net audio result, albeit in much more compact space – you can have hundreds of CDs stored on micro-SD cards the size of thumbnails, rather than the old-fashioned ‘wallets’ bulkily containing mere dozens of CDs.

This is the first part of a new updated series on digital music.  Part two talks about digital music quality parameters.

We”ll be adding a follow-up article that gives you the specifics of the best software to use to rip CDs to FLAC format and how to do so, and the best portable music players to then store/play your music with.

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  9 Responses to “The Devolution of Digital Music”

  1. Very good article, thank you David. I am quite fussy when it comes to listening to audio music. Even so, I have discovered that transferring my huge collection of CD’s to mp3 has not diminished my listening experience at all. My PC is hooked up to premium quality speakers including a modest size sub-woofer. I suggest you try this for yourself as this helps to create a really powerful sound. My stereo system is also premium quality, and I have found using high quality headphones leaves little to be desired.
    A similar debate about camera optics goes on where some photogs swear that this brand or that brand is the best. I’ve been shooting professionally for 30 years and know darn well that the best is only in someone’s imagination and those who praise this or that lens to the max , are often expressing their egotistical viewpoints. Same with vinyl analog and C.D.

    • Hi, Hugh

      It is true that, in many cases, the weakest link in the total sound reproduction chain are the mechanical ‘moving parts’ – ie the speakers or headphones. A low bandwidth MP3 track played through truly high end speakers may well sound better than a CD fed directly into a ‘boom box’ type device.

      I also agree that there is some remarkable nonsense written about sound quality, with some people clearly having a better developed imagination than actual aural sense.

      On the other hand, and at the risk of starting to express the same nonsense I’ve just been condemning, I can’t conceive of how a PC could ever create ‘powerful sound’; at least not unless you take the digital output from the PC then feed it through an external DAC and then into/through a decent amplifier. My reference system uses twin 1000W per channel Carver amps, and while that might seem excessive, it truly isn’t. Remember that sound levels are logarithmic – there is only a 30dB difference in sound level output as between a 1000 W and a 1 W amplifier.

      However, back to reality, and I mean this in the most positive way possible, if you are happy with the sound quality you are experiencing, then you should consider yourself blessed accordingly, because you are able to get good enjoyment out of moderately priced equipment! But I would be curious as to if you could notice the difference if you did a side by side comparison between your MP3 based system and something else.

      Out of curiosity, what rip rate did you use for your MP3s (ie how many kb/sec)?

      • Thanks for your valid comments, Dave. I’m fairly sure that measured side by side, I could notice the difference between mp3 and something of a higher quality – especially if it was pointed out specifically what nuances I was missing. Quality classical recordings would then be the likely medium for comparison, wouldn’t you say?
        And once pointed out, I would probably not go for mp3 and opt for the higher quality medium in that case. But as you mentioned in your article, the space saving mp3 files are a strong reason for changing over, and as most of my 400 CD to mp3 conversions involved pop, rock, jazz and some classical, it was a no-brainer to switch.

        The rip rate I used for conversion was 256kb/sec. which I was more than pleased with. I experimented with 128, but noticed a flatness, or lack of “oomph” in the sound.

        On the subject of audio music, you will recall the first years of transistor radios, where those units used a speakers of approx. 1″ diameter. Those produced a particular sound that we got used to (and really had little comparison to measure against. The family stereo system of the day was good, but wasn’t portable. By all standards the transistor sound was crappy, but the music we listened to was mostly rock, and the bands were often of the ‘garage’ variety – crudely recorded, but did we care?
        Fast forward 50-60 years and nostalgia had us buy CD’s of those golden years. They were re- engineered, tweaked and technically refurbished, andthe result? They didn’t at all have the sounds we were used to. In summary, better is not always so.

  2. Hello again Hugh

    Thanks for continuing to add to this discussion.

    It is interesting that you talk about quality classical recordings. Both the lp record and the CD were both introduced by the release of classical pieces, but I think that too betrays another side to the music/quality snobbishness that sometimes infuses the field (and I say that as a classical devotee, so I feel able to make the comment).

    It is true that many classical music lovers place more importance on the actual sound/texture of the music than do lovers of some of the more modern extreme forms of what is laughably described as music these days. And it is also true that some of the modern/pop/rock music of our youth – ie the 60s/70s or thereabouts – was never recorded to a high standard to start with, meaning that even with the best playback equipment out there, you can’t get more quality out than was present to start with.

    But I think that most forms of music can benefit from better quality. I had an offline exchange of emails with a jazz lover who is passionate about music quality too. And I find, when I do stray into some guilty pleasures of popular music myself, that I prefer it being played back well rather than poorly!

    I do disagree about your comment about space saving however. A decade ago, it was true that there was both a cost and a limit to disk space available, but these days, particularly on a PC, neither really applies. With 1TB and larger external hard drives costing $100 and less, there is no reason to give a second thought to the cost or limits of storage space.

    256k is starting to get acceptably good in terms of quality. It is interesting for me to trace the evolution of my own ripping strategies. When I first started ripping music, I did so at 160k, then when space became more plentiful, I treated myself to 192k, then I went all the way to 320k, and now I’ve of course redone everything in FLAC format which is about 600-700kb/sec.

    The only good news part of this lengthy series of re-rippings is that now I’m maxed out at full CD quality, and until such time as something better than CD should ever appear and become affordable and offer a wide variety of content, that’s as good as it will probably get.

    • Regarding the space saving feature, you are correct. However, I meant it as not having physical CD’s to store, rather than hard-drive space issues. I live in a quite confined space, and not having to deal with the CD volume was a bonus. When transferring, I never fully investigated options other than mp3 as they seemed to satisfy.
      Thanks again. Get better soon Dave.
      Hugh

  3. Apple does support their own lossless format – ALAC. So CDs can be ripped in iTunes and played on iPhones or other IOS devices. Being lossless, the ALAC or FLAC file should each be an exact copy of the CD information. Not sure what the affect of various music apps might be on playback quality.

    • Hi, Frank

      You are correct about the ALAC format, but one is almost always better advised to use an open format that is widely supported rather than a closed proprietary format that is limited to one manufacturer only – even if the manufacturer in question is currently (or was until recently) a dominant player in the relevant marketplace.

  4. The consumer has always chosen portability, or use of use over quality.
    1/2 track Reel to Reel was superior over LP discs.
    When records were popular, so were cassette decks which offered portability with inferior quality to LP.

    The Ipod was basically a Walkman that held hundreds of songs.
    Part of the genius of Steve Jobs was knowing to build what consumer wants with the technology available and make it easy to use. The Ipod when released did push the limits of the technology at the time.

    Today, disks and memory are far larger and can certainly store digital products in higher resolutions than ever before. In order to use better quality headphones to play these mediums as suggested requires more precision or power than most consumers will spend. This will improve over time as well.

    The question is will the consumer pay a premium for better quality, or buy their existing catalog again, or is the existing quality good enough? If they won’t why would the record labels go through the effort?

    Steve Jobs understood better quality, as do many in the industry. It’s rumored that the NeXT computers used a magnesium alloy because he liked the look and feel of it from using his tonearm.

    An SME Model V.

    Thanks.
    Dan Gelman

  5. […] Paradoxically, in the last 15 years, while technological advances now allow for a theoretically better quality of music to be recorded and played back than our ears could ever hope to appreciate, at the same time, issues of convenience and commerciality have seen music quality decline rather than improve. […]

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