Archive for the ‘Bit by Bit (Digital Audio)’ Category

For years now, I’ve been happy to rip all my CDs to MP3 at 320 Kbps using the CDex digital audio extractor, which is open source software and does an excellent job. Many people (i.e. not audiophiles) consider MP3 320 Kbps “CD quality”. It isn’t CD quality, but it’s generally good enough. I rip the CDs so I can put them in iTunes and copy them to my iPod, of course, and I use MP3 compression because it allows me to store about four tracks in the space that it would take me to store one WAV (CD) track.

I’ve recently realized that this one-size-fits-all approach isn’t always the best choice.

I purchased Animal Collective’s most recent album, “Merriweather Post Pavilion” through iTunes. I rarely purchase through iTunes because I’d rather buy the CD and rip my own. However, it was late, the shops were closed, I had a craving for some new music, and after a solid recommendation from All Songs Considered I decided I couldn’t wait.

Lossy Compression

iTunes supplies their music in 256 Kbps m4A file, which many say is on a par with a 320 Kbps MP3 file. Lossy compression is used to convert WAV files to each of these file types, which means information is lost during the conversion process, but at these high bit rates the theory is that most people’s ears won’t notice the difference.

The few iTunes albums I purchased previously sound decent enough. On this occasion I wasn’t satisfied. There was a dense, muddy quality to the recording, and I found the album increasingly unpleasant to listen to with each play.

To be fair, when I wrote to iTunes regarding my issues with “Merriweather Post Pavilion”, they replied with a letter saying that they take the quality of their music very seriously. They also gave me a full refund, even though I didn’t ask them to do that.

Wondering what this album really sounded like, I went off to HMV, where I was lucky to find it in the “2 for €12” rack. As usual, I ripped it to the aforementioned MP3 320 Kbps format…and it still sounded like crap! Hmmm, could it be that my ears were waking up from the induced coma caused by years of listening to compressed music, or was there something else going on here?

“Merriweather Post Pavilion” is a great and unusual album pop album. It sounds a bit like what might really have been going on in Brian Wilson’s head the first time he tried to record “Smile” with the Beach Boys – Lush harmonies and clever melodies overlaid with electronic loops, bleeps, synthesized arpegiators, and other subterfuge, This might not sound very appealing on paper, but it all makes sense when you hear the album. Consequently, it is chock full of sound, which means it is loaded with digital information.

Trying to put this simply, this type of compression works by removing information that isn’t being used, and by making compromises with information that is being used. The less information there is, the happier you are going to be with the results. The more information there is, the more compromises there are. Generally speaking, the differences between WAV and MP3 320 Kbps aren’t glaringly obvious. For example, you might notice a little less sizzle in a cymbal, or the guitars might not be as smooth as when they were captured. However, when there is an above average amount of information, as there is with “Merriweather Post Pavilion”, the compromises can be overwhelming, and MP3 simply isn’t good enough.

The obvious alternative might be to copy the Wav files into iTunes. That is, the files as they exist on the CD (which, by the way, was as sonically pleasing as I hoped when I finally listened to it in this format). In such a case there is no conversion, therefore there is no compression. iTunes and iPods play WAV files, although they do require more processing power, so they’ll run down the battery faster. There are also two other issues with WAV files:

  • Storage space overhead (1 WAV album = about 4 MP3 320 KPs albums).
  • Tagging is not supported (i.e.album information and artwork).

Apple Lossless Compression

Up until now I hadn’t tried any of the so called “lossless” compression formats, which provide some compression but render a file that can be converted back to a WAV file without losing any of the information. You can’t do that with an MP3 file. Also, a lossless file should sound more authentic because you’re retaining significantly more of the information.

In this case, I used the Apple lossless encoder, which I had seen referred to in the discussion boards. Even though I’ve used iTunes for years, I wasn’t aware I had this capability, or what it was, or where it was. It’s well hidden in the preferences (at least to me), and the help file is not particularly illuminating. To set iTunes to rip CDs using the lossless encoder:

  1. Select EditPreferences.
  2. On the General tab click the Import Settings button.
  3. Select Apple Lossless Encoder from the Import Using dropdown list.

“Merriweather Post Pavilion” sounded much better in the Apple Lossless format, but it still wasn’t right. There was obvious coloration so that the overall sound was “darker” and still somewhat compressed. In addition, the expected 40%-50% file size reduction from WAV looked to me more like 30% – definitely not worth it for an inferior version. I should point out that this is the only album I have converted to this format. I suspect that the encoder produces better results with most other albums.

AIFF files

At this point I decided to give up on compression for “Merriweather Post Pavilion”, but I wasn’t satisfied with using WAV files without tagging capability. Tagging is what allows you to include information like artist, album, album cover, genre, etc. When you’ve got ten thousand plus tunes on your box, you want to be able to sort them for easy access. However, there is a format that allows you to have the uncompressed music file with tagging – AIFF.

Even though you may never have heard of them, AIFF files have been around long enough to have wide support. In a nutshell, they place the WAV file information in a new container that can be tagged just like compressed audio formats, although placing that information in the file can require more manual labor than when ripping MP3s, depending on how your software is set up.

What did I learn?

Since having this experience I’ve started ripping new CDs to MP3 and AIFF. Most albums, even my Beatle’s remasters, aren’t as dense and complex as “Merriweather Post Pavilion”, so differences between MP3 320 kbps and AIFF files are far less noticeable, although there is no denying they are there.

MP3 320 Kbps is fine for the road 99% of the time. When you have an album like “Merriweather Post Pavilion”, you’re far better off using the extra space to have a version on your iPod you can stand to listen to. That’s easy for me to say, with a 160GB iPod Classic. But it is worth doing this for the few times it will be necessary.

When at home, why wouldn’t you want to hear the best version of the recording? Sure, this requires more storage space, but hard disk costs have been continually dropping for years. For example, I can now buy a 1 TB external hard drive for half of what it cost for a 300GB hard drive four years ago. There is also something to be said for having a back up copy of your CDs in the event they are lost or damaged.

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Before meandering further through whatever my attention is drawn towards, I thought it might be a good time to ground, center and describe the base of operations that is my computer/music studio/stereo.

A few years ago, I decided to spend some real money and buy a full version of Cubase, a high-spec computer that could run it easily, a professional sounding RME Fireface 400 (we blow our noses in the general direction of SoundBlaster), and a pair of Tannoy active monitor speakers on which to hear it all. If most of that washed over you, never mind. My point is that this is the best sounding (and most expensive) stereo I’ve ever had.

Along with the aforementioned gear, I have an old, beat up mixing desk that I picked up cheap when it was walking past the house one day, under the arm of two musicians looking to upgrade. I also have an assortment of musical instruments. We have five children between us. We live in a big house, but not so big that there is a spare room. But we do have a big kitchen. At least it was big until I annexed one side of it. I am lucky that Trish is a tolerant partner who doesn’t mind. I say “tolerant”. Perhaps she is simply resigned to it and suffering silently. I’m afraid to ask.

When I ordered all the computer-based recording gear, I neglected to order an unlimited supply of time. Also detracting from any serious music production is that this “studio” is located at the somewhat major intersection of living room, backyard, and refrigerator. Anyone with children can appreciate how congested this intersection can be. Now throw in the fact that this is the only computer in the house. So unless everyone is out of the house, or it is very late at night when everyone is in bed, and I’m very, very quiet, the music production just doesn’t happen.

But I can listen to music, a lot of music. Mine, Trish’s, the kids’ – Dad rock, modern pop, rock, country, jazz, hip hop heavy metal – ABBA to Zappa and back again from Zutons to Animal Collective. Don’t think there are any Gregorian chants in the house, but I could be wrong.

Several years ago, every CD in the house was digitized and put on an external hard drive. As a matter of course, all new CDs are ripped to the box the moment they come in the door. In part, I do this because the DVD drive just refuses to play CDs – within a minute the sound speeds up or warbles beyond all recognition. This happens only on the home PC side of the dual-boot computer. On the music production side CDs play just fine, but you can’t do any of the things you might normally do while listening to them, such as check your email, log on to Facebook, or type lengthy, rambling essays. Despite all my tinkering, I haven’t made any impact on this problem.

Having said that, the most important reason I rip is so that I can fulfill my childhood dream of having my own big honking jukebox, which I can use to skip easily between albums or tracks ad nausuem. A little too easily perhaps. For example, if I’m listening to Miles Davis and decide to take out the trash, I may find that when I return a half minute later I’m listening to AC/DC, which was selected by either Not Me or I Didn’t Do It, depending on who you want to believe.

But late at night the house goes quiet and I have the jukebox to myself. One song reminds me of another. I play that, and it leads to the next, and so on. Then suddenly it’s two AM. It’s not my fault. I was abducted by iTunes.

So you see, I spend a lot of time in the kitchen. Good thing I can cook.

No.

Here’s the problem: When CDs first came on the market, record companies were basically taking analog recordings and simply converting them to digital. They didn’t really have the tools or experience to do any different, and even though there were muffled protests, they kept at it with few modifications (after ditching some of the truly awful initial attempts).

Analog (vinyl) has a soft, rich quality to it. It is often smooth and diffused. I’m referring to the auditory feel of the format, not the type of music. Digital, on the other hand, captures everything with unrelenting clarity in 1s and 0s. Back then, straight analog to digital conversion could come out as unnatural as taking your favorite pair of suede shoes and giving them a coat of patent leather shoe polish.  It wasn’t always something you could point to in a tangible way, but it might show up in your ears getting tired easily, or the music feeling a bit brash or harsh, the midrange instruments setting your teeth on edge, that sort of thing.

There is nothing inappropriate about recording music in a digital format, and the results can be as spectacular as vinyl, but you have to understand the properties of each and be able to compensate for them in order to achieve those results.

Mastering includes balancing frequencies, compensating for volume levels, and basically getting an album to feel consistent and sound good throughout.  Like mixing, it’s more of an art form than a science – you can’t just push the Master button. Like other art forms, the materials you use impact on the end result. And that is part of the problem with re-mastering a vinyl album for CD – it can be like one artist trying to create a perfect copy of another artist’s work, while doing so with a completely different type of canvas.

Take, for example, another album that I have now purchased three times: Layla and Other Assorted Love songs by Derek and the Dominos.  Similar to my experience with the various versions of the White Album, I got my first copy shortly after it came out, and it was one of the first albums I replaced when I went to CD. So of course it was one of the initial, dodgy first wave of analog to digital conversions. I tolerated it for years, before buying the Polydor re-master, from the Eric Clapton Remastered series. 

The original vinyl album was one of the best sounding albums I’ve ever bought. I’ll try not to stomp too hard on the hyperbole pedal, but the feel of the album could lift me in ways that few albums ever have. The Polydor re-master goes a long way towards capturing that analog feel, and like the White Album, the clarity of the instruments is outstanding – I can easily distinguish five guitars playing simultaneously during the louder sections of Layla, for example. However, the album is not a 100% match for the vinyl version, and expecting it to be so would be like expecting lightning to strike the same spot twice. Don’t get me wrong. The Polydor version sounds fine, but the original has a wall-of-sound feel that the digital almost, but doesn’t quite, reproduce.

On the other hand, when played next to each other the Polydor version makes the original CD release feel like nails scraping down a chalk board.

Before you go out to replace a well loved vinyl recording, or make a first-time purchase of a legendary classic album, your best bet is to do your homework first. Find out whether there are different versions; each version will be mastered differently. Find out what the audiophiles are saying about it. You may not be able to articulate the differences between versions, but they are there, and you will notice them, even if in subtle ways. Why wouldn’t you want the version that most closely resembles the one that people fell in love with the first time around?

When a CD claims to be re-mastered, what does that mean? Generally speaking, mastering is the art of taking a mix and polishing it to make it sound as good as possible before release. So you would think that re-mastering implies starting that process again, maybe from a fresh mix, to restore the intended sound quality.

The truth is there is no definitive, generic definition of what re-mastering is in the context of digital CDs made from albums originally released in vinyl. To a large extent, it depends on the intentions of those responsible for the release, and what materials they have to work with.

I’ve discussed re-mastering in the context of the Beatle’s White Album, and how a spectacular re-mastering job made it sound pleasantly like the vinyl release. To me, that should be the definition of re-mastering, at least in the context of vinyl to digital conversion.

However, re-mastering can also imply making older recordings sound louder by compressing them, which also produces the adverse effect of flattening out the dynamic peaks and valleys, so that even the “quiet sections seem loud. Whether you’re aware of it, this is one of the ways in which the music industry has been dumbing down your ears over time.

Why are they doing this to our old records? Because that’s what they do to modern recordings. Dynamics used to be a significant tool that record producers would use to evoke feeling. Now, compression is used as a marketing tool to make sure that a track jumps out and grabs your attention while you’re driving 120 KPH down the motorway with the windows down, for example. The track is screaming “pay attention to me!” Problem is, most of the tracks are doing that these days, clamoring for your attention like bored and restless children in the backseat.

It’s exactly the same as when you’re watching TV, and there’s a soft, romantic part, and the man and the woman are whispering so that you can barely hear, and then the HARVEY NORMAN AD COMES ON AND IT BLOODY WELL SOUNDS LOUDER THAN THIS!!!!!! That is compression at work (and in this case, a loud, annoying announcer), and that is what modern pop is giving you on a daily basis. If you’ve been around as long as I have, you shouldn’t be surprised. 40 years ago, Pete Townshend was saying that you had to keep getting louder (i.e. upping the ante) to keep commanding people’s’ attention. Ha ha, remember when the Who were the upper extreme of loud.

If you want to prove this point to yourself, take out some CDs that you’ve had for 20 years and play them next to CDs that have come out in the last few years. I know this is a gross generalization, but in most cases the discrepancy should be obvious.

The best advice I can give you as a CD buyer is this: For a given “re-mastered” album, your best bet is to go online and see what comments or criticisms you can find from listeners, then add a few grains of salt.

Next time: Can’t they just leave the old CDs alone?

I hate buying the same album twice. Three times is definitely too much. But that is exactly what I’ve done with the Beatles White Album.

Why would anyone do such a thing? To illuminate, let me first say that I purchased the vinyl version not long after it was released in the late 60s. As you can imagine, overuse and abuse wore down the grooves and scratched the surface, until it contained more snap, crackle and pop than a family-size cereal box.

When I finally acquired a CD player in the late 80s, I had little hesitation in replacing some of the better loved, but well worn, vinyl releases in my collection. CDs were hot items, as portable as cassettes but much better sounding. No matter how many times you played them, they would sound the same as the first time, they would last forever. There’s a topic for another day. My point is, I bought into CDs big time, and I replaced the White Album with a version that sounded fresh compared to the decrepit one I was replacing.

When the Beatles released the re-mastered versions of their albums last year, I was curious to know whether there would be a noticeable difference, and reluctant to spend any more money on the same album. But when I saw it at Tesco’s for half of what the pre-re-mastered version cost at HMV, my curiosity got the better of me.

I took it home and played it through my stereo/home recording system, which includes a Fireface 400 DA converter and a pair of Tannoy active speakers. Results may vary depending on your system, but my impression was that you would need to have damaged your hearing more than I have over the years not to appreciate the difference that re-mastering made. To me, it was as stark as the difference between 2D and 3D, leaving the older CD sounding rather flat and lifeless.

The first thing I noticed was that you can really hear, and easily distinguish the instruments, especially in the mid range. This is despite the fact that there is loads going on, and was already permanently bounced around a mere 8 tracks and mixed before the mastering came along. For example, the tinny piano that was fighting for attention in “Back in the U.S.S.R.” now has breathing space, and sounds much more natural. Each guitar part is distinct in “Dear Prudence”. On “Ob-La-Di Ob-La-Da”, the hand claps toward the beginning of the song nearly took my head off, not because they were over loud (which they weren’t) but because they were so clear and sharp. Each track brought similar revelations, and I felt like I was listening to the album for the first time.

The second thing I noticed was how the album felt. What I mean is, there is a certain “ahhh” factor of smooth richness that analog (vinyl) recordings had naturally and digital (CD) does not, although there now seems to be the technology and experience to make the latter sound very much like the former. The re-mastered White Album puts the “Ahhh” back in the album. After all these years, Apple has finally released a digital version that sounds as good as the original. Maybe better, since I don’t recall the bass coming out quite that prominently in Helter Skelter, for example.

Verdict: If you’re wondering whether it’s worth upgrading to the re-mastered version, the answer is an emphatic yes. My ears are impressed, my wallet is not.

The downside of this exercise is that it has alerted my ears to the fact that I now own a great number of substandard sounding albums that need to be replaced…again, only this time in the same, if updated, format. The Beatles are only the latest in a long line of artists who have released re-mastered versions of their old vinyl albums on CD, a good few years after they were originally released on CD. I think I’ll be looking into the history of the vinyl to CD transition in the near future to try and understand how this happened.

Those of you who mostly listen to downloaded tracks are probably wondering why you should care about an old workhorse such as CD. Aren’t these being phased out someday soon? Hopefully not, because compared to most commercially available MP3 or MP4 files, CD is the new vinyl. That is, sonically superior. And there is no technical reason why this should be true. In fact, there are some web sites providing a much better download alternative to more popular and successful sites, and that is another topic I’ll get to soon. But for now, if you want a wide selection of good quality recordings, you’re better off with CDs than downloads.