Mere Adequacy is Never Adequate

There are five fundamentals of high-quality digital sound archiving and preservation for analog source material: accuracy, appropriateness, adequacy, consistency, and explicitness.

Previously we examined accuracy (with regard to the source).Today we tackle the next two fundamentals, appropriateness and adequacy (with regard to your processes).

[Image Credit: Sarah Tehan, Aporia, 2013.]

The process of sound archiving and preservation is like scholarly editing. Just as the scholarly edition's basic task is to present a reliable text, the sound preservationist's basic task is to present a reliable digital record of an analog source. In both pursuits, decisions have to be made concerning (re-)construction and representation of the original material to achieve reliability.

Reliability in digital construction and representation of analog sound is a direct result of:

1. Appropriateness: the extent to which a particular process (step) advances accurate sound representation, and the extent which the listener is satisfied with the sound produced.
2. Adequacy: the extent to which a particular process (step) can be shown to be as good as necessary for its purpose or requirement.

The appropriateness and adequacy of the major function groups in the audio archiving and restoration pipeline can be characterized as follows:

• Digital Recording
  Appropriate: Critical first step in the archiving process
  Adequate: 48 KHz minimum sampling rate; 24-bit minimum encoding depth
• Audio Import/Export
  Appropriate: Advances sound data through the processing pipeline
  Adequate: No information lost in transfer
• Format Conversion
  Appropriate: Ultimate sound output in format desired by listener or required by tools
  Adequate: No information lost in conversion; minimal information loss in compression
• Automated Clean/Repair
  Appropriate: Algorithmic processing of common audio artifacts
  Adequate: No artifacts introduced 
• Manual Clean/Repair
  Appropriate: Processing of artifacts unique to a given recording
  Adequate: Minimal audio loss; clipping eliminated; no artifacts introduced
• Track Isolation
  Appropriate: Facilitates playback of individual songs/chapters/passages, etc.
  Adequate: Envelope of silence before and after track
• Volume Normalization
  Appropriate: Addresses volume differences on playlists incorporating multiple titles
  Adequate: Target sound level -0.1 dB for all titles
• Metadata Editing
  Appropriate: Captures relevant information about the original recording
  Adequate: Accurate, and without typographical errors

Another way of characterizing appropriateness and adequacy is that every step in your process must be necessary and your process as a whole must be sufficient. For a step to be necessary, eliminating that step would produce a less-reliable result. A process is sufficient if it is not a failure for having omitted other steps. All magic formulas for success break down on one or both of these criteria. Don't let it happen to you.

             Vinyl-to-Digital Restoration #65            

Artist: Miles Davis
Title: Porgy and Bess
Genre: Jazz
Year: 1958





To quote Dan Epstein: "Take George Gershwin's Porgy & Bess, add Miles Davis and arranger Gil Evans, and what do you get? A classic jazz album that--despite the fact that the material has been rendered almost overly familiar due to countless interpretations--still sounds remarkably fresh four decades after its initial release. Miles' soft yet piercing trumpet style is perfectly suited [TGD: appropriate] to Gershwin's melancholy melodies, Evans' musical direction of his 18-piece orchestra is impeccable [TGD: adequate], and their version of 'Summertime' may well be the finest ever waxed."

© 2014 Thomas G. Dennehy. All rights reserved.

Of All the Charlie Browns in the World, Mine is the Charlie Browniest

The United States Library of Congress voted to designate the Vince Guaraldi soundtrack to A Charlie Brown Christmas a national audio treasure, including it among the twenty-five 2011 inductees to the National Recording Registry — America's sound heritage.

Trouble is, the Library did not have a copy of Charlie Brown among its holdings. So I gave them mine. Here's the story.

Since 2001, the Library of Congress has annually selected 25 sound recordings to be preserved in the Registry of "culturally, historically, or aesthetically significant" recodings. To give you an idea of the diversity among inductees, this year's group also included Prince's Purple Rain and a wax cylinder from an Edison Talking Doll. The press release made me curious: what exactly does the Library archive for any of the recordings and artifacts in the Registry?

In response to email, Library spokesman Cary O'Dell gave this explanation. "For each item selected for the Registry, we attempt to locate and acquire both the earliest and the best format. For example, if a work was originally issued on 78rpm, that is what we will attempt to acquire. Often as well we try to obtain a copy on CD (if one is available) for the ease of researchers." (Apparently we can count the US Government among those who believe the audio CD is a format of convenience, not significance.)

He continued. "Keep in mind that the Library of Congress already holds thousands of records and discs so many of the items named to the Registry we already have a copy of. When Purple Rain started to be discussed, I explored our holdings and found we did already have a vinyl LP. Though we have a digital copy of the Edison cylinder, the original remains in the historic archives of the Edison Labs in Menlo Park [NJ]."

Which brought us to the topic of Charlie Brown. "Another new title this year was A Charlie Brown Christmas. The [National Recording Preservation] Board has discussed it for several years with some members truly singing its praises and importance. This was the year it got enough votes. Surprisingly, we didn't have any holdings of that!" Mr O'Dell concluded, "The Concord Group has since been kind enough to donate a CD of the work to the Library and I am working to obtain an original vinyl."

This was an opportunity too good to pass up. My own vinyl copy of A Charlie Brown Christmas is in storage, having long ago been ephemeralized to 24-bit/96KHz weightless digital format for playback. So I offered to donate it to the Library for induction into the Registry. Mr. O'Dell immediately accepted; the government even paid shipping costs and sent a gracious acknowledgement letter (at right).

The work is currently undergoing a lengthy process of cataloging, curating and digital preservation before it can be counted among the Library's holdings. I'll let you know when the catalog number has been assigned so you can search for it. [Update 14-December: here's the link.]

I am proud that my humble LP is now the definitive audio copy of a beloved classic in the Library of Congress, preserved for posterity. Or, to paraphrase Linus: of all the Charlie Browns in the world, mine is the Charlie Browniest.

                Vinyl-to-Digital Restoration #2 (originally described 1-January-2012)              

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 weightless digital 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 (and a few mastering steps in software) to make it shine. For more on Vince Guaraldi's music, please visit the Impressions of Vince website.

© 2012 Thomas G. Dennehy. All rights reserved.