Appendix C. Terms for describing the physical condition of sound recordings

Contents:

C.1. Introduction
C.2.Terms to describe common conditions
C.2.1. Discs and cylinders
C.2.2. Tapes
C.2.3. Wire recordings
C.3 Extent of condition

 

C.1. IntroductionThe following is a brief list of English language terms and definitions relating to common condition problems of recorded sound discs and magnetic tapes. It is offered to assist with describing the condition of sound recordings in Area 7 (see 7.B.15).

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C.2. Terms to describe common conditions

C.2.1. Discs and cylinders

Note that some of the terms in this section, especially where shellac discs are indicated, are also applicable to cylinder recordings.

Bleeding. Inks or dyes on the label of the disc are running.

Blister. Often caused by entrapped steam or air inclusion at the time the pressing was made. Causes clicks or other transient noise during playback.

Broken. The disc has broken into distinct parts (generally applies to shellac or glass-based lacquer discs, or to cylinders).

Centre damage or fault. The centre hole is chipped or otherwise unfit for centering the disc.

Chemical residue. Residue from a cleaning fluid or other chemical is on the surface of the disc.

Chinagraph mark. The grooved surface of the disc has chinagraph crayon markings.

Chip. A small piece is missing, usually from the edge of a shellac disc or cylinder.

Corrosion. The metal substrate of a lacquer disc or of a metal part (e.g. stamper, mother) displays rust or some other form of corrosion.

Cracked or Cracking. A break without physical separation (generally applies to shellac discs and cylinders only)

Crazing. Thin fracture lines occurring on the surface of a lacquer disc caused by shrinkage of the lacquer with respect to the substrate.

Darkening. Colour change in disc. May be caused by ageing or by temperature problems at the time the disc was pressed.

Dust or Dirt (Dirty/Oily). Dust, dirt or oiliness on the surface of the disc, usually resulting from poor storage conditions and handling.

Foreign matter. Usually describes material (cardboard, etc.) which has become adhered to or embedded in the surface of vinyl or shellac discs or cylinders following manufacture (as opposed to inclusion).

Gouge. Large, deep scratches. This was sometimes done deliberately for contractual and copyright reasons to prevent further replay.

Inclusions. Foreign matter (e.g. small fibre, or grain of sand or mineral) included in the material from which the disc or cylinder is made. If at the surface of the carrier, it may be visible to the eye, and may also fall out and leave a cavity. If below the surface, it may manifest as a lump or blister. May or may not affect playback.

Label damage. The label is worn away, eaten by insects, or similarly affected.

Loose pieces (Flaking). Pieces of lacquer have partially come away from the substrate of a lacquer disc.

Marks (Marked). Marks such as fingerprints and scuffs occurring on the grooved surface.

Missing pieces. Denotes shellac or lacquer discs with missing pieces, which, as a result cannot be consolidated.

Misstracking (Repeating or skipping grooves). The stylus or needle repeats or skips a groove unless a sideways force is applied at the right time during playback. Usually caused by a breakdown in groove wall, or a gouge.

Mould (Mouldy). Usually takes the form of white or grey patches on the surface, with a characteristic structure visible under low power magnification. Exacerbated by high humidity or by contact with organic material.

Needle dig. A very localised gouge due to a dropped soundbox with needle.

Needle run. Curved scratch due to inappropriate handling of the soundbox causing multiple ticks over the whole playing surface.

Orange peel effect. A grainy or textured surface caused by the pressing being too hot when made, or heat applied to it afterwards. Can result in an increase in background noise.

Out-of-round. The circular section in a cylinder is eccentric, elliptic, or not round in some other way. It may give a 'wow' effect to the sound during playback.

Peeling. Failure of the bonding between the substrate and the lacquer layer. Results in large sections of the surface, or sometimes the entire face, peeling away from the substrate of the lacquer disc.

Scratches (Scratched). Grooves scored with narrow lines. The result of poor handling.

Stitching. A pattern resembling a series of small dashes or stitches running along the grooves of a disc caused by wear from a stylus with insufficient compliance or excess tracking weight on more heavily modulated, low-frequency sections.

Warp. Alteration in disc surface shape (usually along several planes), causing the stylus to jump when the disc is played. Due to heat and/or uneven physical pressure on the disc.

Waxy exudate. A waxy substance exuding from the surface of the disc. May be caused by a reaction between plasticisers in lacquer discs, and the packaging. Some shellac discs had excess or unstable wax in the binder which leaves a 'bloom' on the disc's surface. Often exacerbated by storage conditions.

Wear (Worn). Worn groove walls, caused by stress of overuse, or replay with worn or inappropriate stylus. Often not easily seen with the naked eye, but appears as an overall dullness or grey grooves. It is more likely to occur during loud passages, and results in increased surface noise and decreased high frequency response. In some sound and audiovisual archives this is scaled from 1 (brand new, perfect copy) to 6 (looks dreadful but still playable) (see also C.3).

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C.2.2. Tapes

Backcoat shedding. Backcoat particles coming away from the substrate and accumulating on surfaces in contact with the back of the tape. Apart from the loss of functionality of the backcoat itself, loose debris can deposit on the playing surface of the adjacent layer of the tape, impairing playback quality (as opposed to magnetic coating shedding or magnetic coating lift).

Bleeding. Inks or dyes on the surface or writing on the backcoat, seeping through the tape layer.

Blocking. Whole blocks of adjacent layers of tape have shifted sideways relative to the rest of the tape pack. Usually the result of horizontal storage, transport or rough handling. Blocking can result in damage to the edges of the tape and localised stress where lateral movement has occurred.

Brittleness. Tape breaks easily. Cupping and curvature may also be present.

Cinching. The rippling of tape layers when bunched up from pack slippage or uneven tension. Cinching can permanently deform the substrate, resulting in rapid, cyclical fluctuations of sound level, as the creased tape passes across the playback heads.

Cupping. Curvature across the tape's surface, rather than along its length. Due to the substrate and recording layers having different rates of shrinkage.

Curvature. Tape has a tendency to stay rolled up. Modern PET based tapes have more of a tendency to 'remember' the shape in which they are packed and to flow or deform plastically in response to pressures and stresses within the pack.

Damaged reel (or cassette or cartridge casing). The hub, flange or spool of a tape reel or the casing of a cassette or casing is damaged. This may cause damage to the tape if it touches the reel or casing during playback, re-wind, fast forward, or even when in storage (where clamp indents or clip impressions may occur). Note that the flange or casing should never touch the tape.

Dust or Dirt (Dirty/Oily). Dust, dirt or oiliness on the surface of the tape, usually resulting from poor storage conditions and handling.

Edge damage. Edge of tape is not straight or not flat. This can cause dropouts, reduced output level, or a random shift in the stereo image of the recording.

Embossing. Physical damage to a tape caused by foreign matter that has become embedded within the tape pack, or by deformities in the hub.

Gummy deposit. Glue-like substance on the tape. It accumulates on the heads and guides of the playback machine when the tape is played.

Hydrolysis. Breakdown of the binders in the tape due to its reaction with moisture. Any shedding, sticking, squealing or residue may be a sign of hydrolysis.

Interlayer adhesion. The surface of one layer of tape is sticking to the back of the succeeding layer.

Kink. A crease on a layer of tape.

Leafing. Single layers of tape are protruding from the tape pack. Usually this is the result of spooling too quickly for the tension/alignment of the transport, and for the characteristics of the tape, causing momentary entrapment of air between layers. Leafing may occur individually or in groups, and exposes tape edges to potential damage.

Loose wind. Individual layers of tape are loosely wound on the tape pack. This is due to lack of fastening of the end of the tape. It may cause slippage of the tape pack on playing, and lead to cinching.

Magnetic coating lift. Coating layer separates from the substrate in sheets, indicating a failure of adhesion to the substrate (as opposed to backcoat shedding).

Magnetic coating shedding. Magnetic coating particles coming away from the tape substrate and depositing on heads and guides of playback machine. Due to a loss of cohesion (as opposed to backcoat shedding).

Magnetic losses. The tape has been partially or fully demagnetised or suffered from a loss of signal due to deterioration of the magnetic coating. (E.g. a section of the tape has been accidentally exposed to a bulk eraser, or magnetic particles may have physically deteriorated, resulting in a weaker signal).

Manufacturing surface defect. Includes partial lack of coating, foreign inclusions, variations in width, edge finish or thickness, etc.

Mould (Mouldy). Usually takes the form of white or grey patches on the surface, with a characteristic structure visible under low-power magnification. Exacerbated by high humidity or contact with organic material.

Scouring. Fine scratches on the surface of a tape usually caused by stationary guides or rough tape heads.

Splice. Small piece of special adhesive tape used to join two pieces of recorded material to form a single piece.

Splice, dry (Dry splice). Adhesive on splice is dry, or the splice is brittle. It results in drop-out of sound at the splice and on the adjacent tape layers where the adhesive has left a deposit. A dry splice may come away during playback.

Splice, sticky (Sticky splice). Adhesive from the splice sticks adjacent layers of tape together and can cause information drop-outs where the adhesive has left a deposit.

Spoking. Radial lines or spokes appearing in a tape pack, caused by adjacent layers of tape suffering similar deformation(s).

Squealing. High pitched noise caused by bowing action of tape on heads. May result from hydrolysis and/or loss of lubricants. May be accompanied by stiction.

Stiction. Tape sticks to heads and guides on the playback machine, and will not spool or play.

Stretch. Tape is deformed by stretching, and is usually elongated, narrowed and cupped.

Vinegar syndrome. Technically, de-acetylation of cellulose acetate substrates which may produce acetic acid as a by-product, and gives rise to the characteristic vinegar odour. May be accompanied by brown or white crystals on the tape pack.

Windowing (Windows). Deformation of the layers of tape within the tape pack to the extent where light can be seen through it.

Wrinkle. Multiple creases in the tape.

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C.2.3. Wire recordings

Corrosion. Occurring usually as rust with some wire recordings.

Wire knots. When wire recordings break away, the broken ends may be tied together. This tie forms a knot.

Wire tangles. Tangled recording wire. The thickness of fuse wire, recording wire tangles easily when it is unspooled.

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C.3. Extent of condition

It is also useful to give some indication of the extent to which the recorded sound item is physically affected by the condition. A simple or elaborate rating system may be developed which is appropriate to the requirements of the archive or cataloguing agency. For example, terms which could be applied in a simple rating of the extent of each condition would be: Slight, Medium or Extensive.

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