Monday, May 21, 2018


Nine months after promising myself that I would upgrade my iPod nano to a Sony Walkman [link], I have done exactly that, when the iPod stopped working for a few days. I have now launched headlong into the devotional task of loading my CD collection of twenty-plus years onto it – the first purchase, from Virgin Megastore in Portsmouth, was of “Jagged Little Pill,” by Alanis Morrissette, and “Now 35.”
Apparently, my NW-A45 Walkman can play “HD Audio,” which Sony defines as anything above CD quality. I had not looked into this before buying it, as my main intention was to find something that can accept a 200 Gb micro SD card – Sony says it can take a card with ten times that capacity, but none has been made yet. However, if this Walkman is expected to beat CD quality, then I can leave MP3 behind: in 2015, Ryan Maguire reconstructed a version of Suzanne Vega’s atmospheric song “Tom’s Diner,” used in the 1990s as a control when testing the “lossy” codec that compresses sounds into MP3 format, that only plays the sounds that were, in effect, discarded – enough sound is left behind for you to still identify the song as “Tom’s Diner.”
After some research, I now have the definitive advice for converting your CDs, which I will be using on my entire collection: only use FLAC (Free Lossless Audio Codec) format, setting it to 44.1 kHz 16-bit if you have the option, because this matches the settings of the CD.

The “lossless” element of FLAC, a format that has been around since 2001, means all the available information on your CD is being retained. Because of this, you do not set a bitrate of kilobits per second like you would with MP3, because that rate will change with the song. Using the first CD I converted, “Hot Potatoes: The Best of Devo,” there is a difference based on the type of song: “Devo Corporate Anthem,” a simple fanfare, reaches a maximum of 655 kbps, while “Through Being Cool,” a more involved, complicated, recording has a maximum of 871 kbps. A few Bee Gees tracks I have break the 1,000 kbps barrier, louder and richer than the Devo recordings, which proves what you can still get from a CD if it has been mastered correctly.
Put in as simple a manner as I can, CDs use a 44.1 kHz sample rate because it is twice the 20Hz to 20 kHz range of the human ear – it also matched the highest usable rate for recording digital audio on video tape - while the 16-bit pulse-code modulation used to digitise the sound, the latest development of a technology initiated to reduce the noise in long-distance phone calls, means the amount of detail picked out by the technology is more than “enough,” with a grove that won’t wear out like vinyl will.
What this does mean is that, if you have a CD that is “24-bit remastered,” this is talking about the digital master used to make the CD, which will still be 16-bit, even if more detail is available to sample. As an example, I have a 24-bit remastered copy of David Bowie’s album “Never Let Me Down,” but I also have the original 1987 release, because Bowie hated the song “Too Dizzy” enough to leave it off all subsequent reissues. The song “Beat of Your Drum,” with a chorus sounding like Bruce Springsteen’s “Glory Days,” is 34.3 Mb in size when taking a FLAC copy from the 1987 album, but the 24-bit mastered version raises this to 36.6 Mb – the difference is there, but you need a very quiet room to start with.

But with Sony highlighting the enhanced “experience” of HD Audio, the extra resonance adding to the recording, I feel like I have already achieved that, for now, by leaving MP3 behind, regaining the lost layer of sound from my, in some cases, decades-old CDs.

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