Difference between revisions of "Audio Specifications and Standards"

From UA Libraries Digital Services Planning and Documentation
(Resources and Links:)
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====Associated Hardware/Software====
 
====Associated Hardware/Software====
 
*see [[Digital Audio Workstation (DAW)]]
 
*see [[Digital Audio Workstation (DAW)]]
 +
 +
==Care, Handling, and Storage of Analog Audio Materials==
 +
 +
Audio preservation
 +
Potential degradation issues:
 +
*Open Reels
 +
**Obsolescence – lack of equipment being manufactured of available to play the format
 +
**Cellulose acetate base – Cellulose acetate degrades in water so tapes with a cellulose acetate base are susceptible to hydrolysis which creates vinegar syndrome. Vinegar syndrome occurs when acetic acid is released and accelerates the degradation process.
 +
**Sticky shed syndrome – polyester based tapes have a urethane binder that when subjected to hydrolysis sheds the backing when played across the guides.
 +
**Fungus – tapes in high temperature and humidity causes tapes to grow mold or fungus.
 +
*Laquer discs and aluminum discs
 +
**Plasticizer exudation – failure of the coating and loss of content
 +
**Oxidation
 +
 +
Casey, M., & Feaster, P. (2009). Media preservation survey: A report (pp. 1-132, Rep.) (A. Burdette, Ed.). Bloomington, IN: Indiana University Bloomington.
 +
 +
===Best Practices for storage and handling:===
 +
*Wash hands
 +
*Keep materials stored in a clean place
 +
*Don’t touch playing surfaces
 +
*Keep playback equipment clean
 +
*Allow time for acclimation between storage rooms
 +
 +
Discs
 +
 +
*Handle discs by the edge
 +
*Handle optical discs by the hole
 +
*Store discs upright and on edge
 +
*Do not store discs with different diameters together
 +
*Store in polyethylene sleeve
 +
 +
Open reel
 +
 +
*Store on unslotted hubs
 +
*Handle by the edge of reel or by the center
 +
 +
Cassettes
 +
 +
*Handle by outer shell
 +
*Don’t touch spools
 +
*Store played tapes without rewinding just rewind them right before you play
 +
 +
General Storage
 +
*Keep in a cool dry room, 65-70 F and 35-50% relative humidity
 +
*Keep materials away from light, magnets and sources of vibration
 +
 +
Library of Congress. (n.d.). Care, Handling, and Storage of Audio Visual Materials. Retrieved May 02, 2016, from http://www.loc.gov/preservation/care/record.html
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 +
 +
  
 
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<hr>

Revision as of 14:43, 2 May 2016

Introduction:

The following provides a brief overview of our standard audio specifications.



Technical Information:

Default File/Output Settings

  • masters: .wav/WAVE at 24-bit/44.1khz
    • note: IASA TC-04 calls for a minimum sampling rate of 48kHz (preferably 96kHz). We will discontinue use of 44.1kHz sampling rates pending confirmation of appropriate storage space as 24/48 vs 24/44.1 should yield only an 8% increase in space requirements. Projects already underway at the 24/44.1 spec will maintain that specification. - arora, 062910. Update: given remaining storage concerns, we will continue with 24/44.1. - arora, 030911.
    • typically, 2s of silence is left or created at the beginning of each .wav, with 1s at the end.
    • RMS levels are typically set fairly low, to -25db
  For information on derivatives, see For_Creating_Derivatives

Associated Hardware/Software

Care, Handling, and Storage of Analog Audio Materials

Audio preservation Potential degradation issues:

  • Open Reels
    • Obsolescence – lack of equipment being manufactured of available to play the format
    • Cellulose acetate base – Cellulose acetate degrades in water so tapes with a cellulose acetate base are susceptible to hydrolysis which creates vinegar syndrome. Vinegar syndrome occurs when acetic acid is released and accelerates the degradation process.
    • Sticky shed syndrome – polyester based tapes have a urethane binder that when subjected to hydrolysis sheds the backing when played across the guides.
    • Fungus – tapes in high temperature and humidity causes tapes to grow mold or fungus.
  • Laquer discs and aluminum discs
    • Plasticizer exudation – failure of the coating and loss of content
    • Oxidation

Casey, M., & Feaster, P. (2009). Media preservation survey: A report (pp. 1-132, Rep.) (A. Burdette, Ed.). Bloomington, IN: Indiana University Bloomington.

Best Practices for storage and handling:

  • Wash hands
  • Keep materials stored in a clean place
  • Don’t touch playing surfaces
  • Keep playback equipment clean
  • Allow time for acclimation between storage rooms

Discs

  • Handle discs by the edge
  • Handle optical discs by the hole
  • Store discs upright and on edge
  • Do not store discs with different diameters together
  • Store in polyethylene sleeve

Open reel

  • Store on unslotted hubs
  • Handle by the edge of reel or by the center

Cassettes

  • Handle by outer shell
  • Don’t touch spools
  • Store played tapes without rewinding just rewind them right before you play

General Storage

  • Keep in a cool dry room, 65-70 F and 35-50% relative humidity
  • Keep materials away from light, magnets and sources of vibration

Library of Congress. (n.d.). Care, Handling, and Storage of Audio Visual Materials. Retrieved May 02, 2016, from http://www.loc.gov/preservation/care/record.html




Resources and Links: