Showing posts with label FLAC. Show all posts
Showing posts with label FLAC. Show all posts

Monday, January 9, 2012

A Xerox of a Poloroid of a Photo of a Painting

What format and bit rate should you choose for ephemeralizing your LPs?

While it may be popular, lossy compressed audio has its detractors. In an interview, Grammy-winning producer T. Bone Burnett likened its fidelity to the sonic equivalent of "a xerox of a poloroid of a photo of a painting."

[Image: low-res Beatles Sgt. Pepper album cover.]


Nonetheless, the 256 KBit/sec MP3 has become the de facto standard for purchasing and streaming music in the cloud.

Like WMA and AAC, MP3 is a lossy compressed format. (The three formats are interchangeable for the purpose of this discussion.) You can't uncompress an MP3 and get back the original audio. Some information is thrown away in the compression process to gain additional compaction over lossless compressed formats.

Lossless uncompressed formats incorporating linear pulse-code modulation (LPCM) capture a direct digital representation of an analog wave. "CD-quality" uses 16-bit samples taken at 44.1 KHz. The equivalent bit rate of 1411.2 KBit/sec transmits more than 5x the information in MP3 audio, with no loss due to compression. (See figure at right.)

Even a CD-quality copy introduces downsampling from the original. Most digital studio recordings are made with 24-bit samples taken at 96 KHz. The equivalent bit rate of 4608 KBit/sec transmits 18x the information in MP3 audio and more than 3x the information in CD audio.

It is possible to make 24-bit/96KHz recordings at home, 18x richer than a "good" MP3. Gigahertz computer clocks facilitate high sampling rates. Near-zero cost of storage makes compression unnecessary.  But is it worth generating and storing all those bits? Can anyone really hear the difference?

My Harman colleague Dr. Sean Olive, Director of Acoustic Research, is actively seeking a scientific answer to that latter question. My answer is simple: I don't care.

When it comes to information, more is always better. The digital transfer pipeline is software-driven. You may or may not be able to "hear" the difference, but your software tools can "see" the difference and work better when they have more to chew on. I'll use use the next couple posts to try to convince you to seek and preserve as many bits as possible when recording and processing, even if you ultimately choose a compressed format in which to store and enjoy your end products.


              Analog-to-Digital Restoration #8             

Title: Diamonds and Pearls
Artist: Prince & the New Power Generation
Genre: Soul and R&B
Year: 1991



Everything we've said regarding digital transfer of LPs applies identically to other analog source material. If you still have the equipment to play something, you can usher it into the digital future. I recently bought a like-new Denon DRS-810 at an estate sale for $25—a real find—to add to my recording station. My wife's equally like-new cassette copy of this Prince title is now ephemeralized.


© 2012 Thomas G. Dennehy. All rights reserved.

Sunday, January 1, 2012

LPs and CDs are Just Install Discs for Music

Rather than being crushed as a relic of the past, vinyl can be an active participant in the digital music future. Let me explain.

Before I embraced my inner Detroit-ness and got into the automotive business, I worked for a CAD software company.

When I started, our products were mostly delivered as "shrink-wrapped software"—a sealed box containing a CD and a manual. You used the CD to install the software, then put it in back in the box and stored the package in a closet never to be seen again (barring the need to re-install after disaster).

In later years it became more common for customers to download an installer and purchase an authorization key to enable use. Today many software products have now been replaced with cloud-based software services, requiring no local installation.

The parallel to music is obvious. The industry has evolved from physical media to digital downloads to cloud-based streaming.

Now that dematerialized play is the norm in my house, my preferred delivery mechanism for music is a download in lossless format. If a lossless download is not available, I reluctantly purchase a CD. The CD is used exactly once, to "rip" its content to the Library, then stored away in a cabinet never to be seen again.

Basically, the audio CD has been reduced to an install disc for music.

If you enjoy the sonic characteristics of vinyl but want the cool features of dematerialized play, the LP can just as straightforwardly be a music install disc for a given title, using a high-quality digital transfer process. For me, that covers all music purchased before 1985 or so. But an LP can be used to install new releases from artists like The Black Keys, She & Him, Leonard Cohen, Wilco, and the late Amy Winehouse — all available on vinyl.

While ripping a CD is a mindless install operation — a background task — the LP install process requires your full attention: recording at high resolution, carefully repairing old wear-and-tear, meticulously isolating and labeling tracks for export, and studiously suppying metadata. An LP is "decidedly invonvenient, which is the very reason it appeals." (Eric Felton)

Another example of how CDs and LPs are fraternal, but not identical twins.

               Vinyl-to-Digital Restoration #2              

Title: A Charlie Brown Christmas
Artist: Vince Guaraldi Trio
Genre: Jazz/Christmas
Year: 1965



There are two CD copies of A Charlie Brown Christmas somewhere in my house. But when it came time to install this title in my dematerialized Library, I decided to dub the old LP copy rather than ripping a CD. Like the homely Christmas tree selected by Charlie Brown, all the LP needed was a little love to make it shine.


© 2012 Thomas G. Dennehy. All rights reserved.