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Ab und zu ist es wichtig, mal nachzulesen, was denn die Amerkaner damals unter diesem oder jenem Begriff verstanden.

Um die schleppende Entwicklung des Magnetbandes in den USA zu verstehen, muß man zwei Geräte kennen,

1. die Kügelmühle und
2. den Kalander

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Eine Kugelmühle wurde erfunden, um jegliches harte Material in allerfeinste Stäube zu zermahlen. Um zum Beispiel magnetisierbares Eisen oder Eisenoxid als Staub gemahlen mit einer Kunsstoffmischung absolut gleichmäßig zu vermahlen und zu vermischen, sind hunderttausende von Präzisions-Stahlkugeln in dieser als eine große Trommel ausgelegten Mühle mit dem Kunststoff und dem bereits zerkleinerten Eisenmaterial eingefüllt.

Die Trommel mitsamt den Eisenkugeln wird über Wochen auf eine bestimmte Temperatur geheizt und dann mit den beiden zu mischenden Stoffen gefüllt und dann rollt sie - weiter beheizt - wiederum Wochen - bis der gemischte Brei oder die Suppe fertig ist.

Jetzt kommt der Kalander ins Spiel. Dieser Brei wäre das Rohmaterial für ein sogenanntes Masseband, ein Magnetband, bei dem die Trägerschicht und die Magnetschicht zusammen gehören. Und dieser Brei wird zwischen zwei unglaublich präzise Walzen eingefüllt und hinten kommt ein absolut gleichmäßiges nur 14 müh dickes etwa 50cm breites Magnetband heraus. Man könnte damit auch das extrem dünne durchsichtige Tesa-Klebeband herstellen.

Doch das konnten die Amerikaner zu der Zeit um 1946 noch nicht. Denn deren 3M Klebeband war viel viel dicker und auch kräftiger. Das mußten sie - zusammen mit Ampex und Jack Mullin und seinen 50 Rollen Magnetophonband erst noch lernen.
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(Editor's Note - We wish to thank the publishers of "The Proceedings of the I.R.E." for their cooperation in allowing us to reprint "Glossary of Disc-Recording Terms" (prepared by Recording and Reproducing Standards Committee of the National Association of Broadcasters) in this, and subsequent issues of Audio Record.)

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• Abrasive:
  The grinding material sometimes incorporated in record stock for the purpose of shaping the needle point to fit the groove properly.
• Acetate disc:
  Various acetate compounds used for solid and laminated (which see) discs. The term is often erroneously used to describe cellulosenitrate discs (which see).
• Advance ball:
  A rounded support (often sapphire) attached to the recording head which rides on the discs to maintain a uniform mean depth of cut by correcting for small variations in the plane of the disc surface.
• Angle of Groove:
  The angle from wall to wall of an unmodulated groove in a radial plane perpendicular to the surface of the disc.
• Backed stampers:
  A thin, metal matrix (which see) which is attached to a backing material, generally a metal sheet 1/8" to 1/4" inch thick.
• Binder:
  A resinous material which causes the various materials of a record compound to adhere to one another.
• Biscuit:
  A small slab of the stock material, from which records are pressed, as it is prepared for use in the presses.
• Blank groove:
  A groove upon which no modulation is inscribed.
• Burnishing surface (of cutting stylus):
  The portion of the cutting stylus directly behind the cutting edge which smoothes the groove.
• Burnishing tool:
  The stylus sometimes used to smooth the groove of a recording
• Cake Wax:
  A thick disc of wax (which see upon which an original recording is inscribed.
• Capacitor pickup:
  A phonograph pickup which depends for its operation upon the variation of its capacitance.
• Carbon-contact pickup:
  A phonograph pickup which depends for its operation upon the variation in the resistance of carbon contacts.
• Cellulosenitrate Discs: See Lacquer discs.
• Center hold:
  The hole in the center of the record, which fits the center pin of the turntable.
• Center pin:
  The shaft protruding from the center of the turntable used for centering the record.
• Chip:
  The material removed from the disc by the recording stylus in cutting the groove.
• Christmas-tree pattern:
  A term sometimes used in referring to the optical pattern (which see).
• Condenser Pickup: See Capacitor pickup.

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(Glossary of Disc-Recording Terms will be continued in the March 1946 issue of Audio Record.)
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Aber diese Ausgabe fehlt leider.
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• Dynamic pickup:
  A phonograph pickup in which the electrical output results from the motion of a conductor in a magnetic field.
• Eccentric circle:
  A blank, locked groove (which see) whose center is other than that of the record (generally used in connection with mechanical control of phonographs) .
• Eccentricity:
  The eccentricity of the recording spiral with respect to the record center hole.
• Fast spiral:
  A blank, spiral groove having a pitch that is much greater than that of the recorded grooves.
• Feedback cutter:
  A cutter provided with a feedback circuit (separate from the driving circuit) in which a voltage, for inverse feedback to the driving amplifier, is induced by the movement of the cutting stylus.
• Filler:
  The bulk material of a record compound as distinguished from the binder (which see).
• Flowed-wax platter:
  Disk base (usually metal) upon which wax is flowed.
• Flutter:
  Frequency modulation caused by spurious variations in groove velocity.
• Frequency record:
  A record upon which have been recorded various frequencies throughout the desired frequency spectrum.
• Groove:
  The track cut in the record by the stylus.
• Groove contour:
  The shape of the groove in a radial plane perpendicular to the surface of the record.
• Groove speed: See groove velocity.
• Groove velocity:
  The linear velocity of the groove with respect to the stylus.
• Grouping:
  Nonuniform spacing between grooves.
• Guard circle:
  An inner concentric groove inscribed on a record to prevent reproducer from being damaged by being thrown to the center of the record.
• Hill-and-dale recording: See vertical recording.

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(Glossary of Disc-Recording Terms will be continued in the June issue of Audio Record.)
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• Hot plate:
  A heated table used for (a) softening the biscuits of record material prior to placing them in the press or (b) making flowed waxes.
• Instantaneous recording:
  A recording which may be used without further processing.
• Label:
  The identification markings on paper or similar material, at the center of the record.
• Lacquer discs:
  Discs, usually of metal, glass, or paper, which are coated with a lacquer compound (often containing cellulose nitrate) and used either for "instantaneous" recordings or lacquer masters.
• Lacquer master:
  A term improperly applied to a "lacquer original" (which see).
• Lacquer original:
  An original recording on a lacquer disc which is intended to be used for the making of a metal master.
• Laminated record:
  A disc composed of several layers of material. Normally used with one thin facer on each side of a core.
• Land:
  The record surface between two grooves.
• Lateral compliance:
  The ability of a reproducing stylus to move laterally with respect to the record groove while in the reproducing position in a record.
• Lateral recording:
  A recording in which the groove modulation is in the plane of the record and along a radius.
• Lead screw:
  The threaded rod which leads the cutter or reproducer across the surface of the disc.
• Lead-in spiral:
  A blank, spiral groove at the beginning of a record, generally having a pitch that is much greater than that of the recorded grooves.
• Locked groove:
  A concentric, blank groove at the end of modulated grooves whose function is to prevent further travel of the reproducer.
• Magnetic pickup:
  A reproducer employing an armature placed in a magnetic field and coupled mechanically to the reproducing stylus. An electric potential is generated in a coil placed in this field when the stylus is actuated by the modulated groove of a record.
• Mother:
  A positive produced directly from the metal master or negative.

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• Needle: (reproducing needle):
  A replaceable reproducing stylus (which see).
• Needle drag:
  Same as stylus drag (which see).
• Needle pressure:
  Same as stylus pressure (which see).
• Optical pattern:
  The pattern which is observed when the surface of a record is illuminated by a beam of parallel light.
• Orange peel:
  Mottled surface of a defective disc having an appearance similar to the skin of an orange.
• Original reccrding: See lacquer original and wax original.
• Overcutting:
  Excessive level in recording to an extent that one groove cuts through into an adjacent one.
• Pickup:
  A mechanicoelectrical transducer which is actuated by the undulations of the record groove and transforms this mechanical energy into electrical energy.
• Pinch effect:
  A pinching, or in some cases a lifting of the reproducing stylus, twice each cycle in the reproduction of lateral recordings, caused by the recording stylus cutting a narrower groove when moving across the record while swinging from a negative to a positive peak.
• Playback:
  An expression used to denote the immediate reproduction of a recording.
• Poid:
  The curve that the center of a sphere traces when the surface of the sphere is rolling along a sine wave.
• Postemphasis:
  The complement in reproduction of pre-emphasis (which see).
• Pre-emphasis:
  A method of recording whereby the relative recorded level of some frequencies is increased with respect to other frequencies.
• Pressing:
  A record produced in a recordmolding machine from a matrix or stamper.
• Processing:
  Making the master, mother, and matrix (which sec).
• Recording head:
  Same as cutter (which see).
• Re-recording:
  A recording made from the reproduction of a recording. (See also dubbing.)
• Reference recording:
  Recording of a program or other material made for the purpose of checking same.
• Reproducing stylus:
  The "needle" or jewel which follows the undulations in the record groove and transmits the mechanical motion thus derived to the pickup mechanism.
• Rumble:
  Low-frequency vibration mechanically transmitted to the recording or reproducing turntable and superimposed on the reproduction.
• Safety:
  A second recording, made simultaneously with the original, to be used for duplication should the original be damaged.
• Shaving:
  Process of removing material from a wax disc of recording material to obtain a plane surface.
• Shell or shell stamper:
  A thin metal matrix (generally 0.015 to 0.020 inch thick).
• Spew:
  The excess record material which is ejected from the record press in the manufacture of pressed records.
• Spread groove:
  A groove, with greater than normal pitch, cut between recordings of short-time duration, thus separating the recorded material into bands while still enabling the reproducing stylus to travel from one band to the next.
• Sputtering:
  A process sometimes used in the production of the metal master, wherein the wax or lacquer original is coated with an electrical conducting layer by means of an electrical discharge in a vacuum. Sometimes called cathode sputtering.
• Stamper:
  A negative (generally made of metal) produced from the mother (which see) and from which the finished pressings are molded. (See also matrix.)
• Stylus drag:
  The expression used to denote the effect of the friction between the record surface and the reproducing stylus.
• Stylus force:
  Effective weight of reproducer or force in vertical direction on stylus when it is in operating position.
• Stylus pressure:
  Term sometimes erroneously used to denote effective weight of reproducer or stylus force (which see).
• Stylus weight:
  Actually stylus force (which see).
• Surface noise:
  The noise reproduced in playing a record due to rough particles in the record material and/or irregularities in the walls of the groove left by the cutting stylus.
• Throw-out spiral:
  A blank spiral groove at the end of a recording, generally at a pitch that is much greater than that of the recorded grooves.
• Throw-out tail:
  End of throw-out spiral (which see).
• Tracing distortion:
  A harmonic distortion introduced in the reproduction of records because of the fact that the curve traced by the center of the tip of the reproducing stylus is not an exact replica of the modulated groove. For example, in the case of a sine-wave modulation in vertical recording, the curve traced by the center of the tip of a stylus is a "poid" (which see).
• Tracking error:
  The angle (in a lateral recording) between the vertical plane containing the vibration axis of the mechanical system of the reproducer and a vertical plane containing the tangent to the record groove.
• Transition frequency:
  The frequency at which the change-over from constant-amplitude recording to constant-velocity recording takes place.
• Translation loss:
  The loss in high-frequency reproduction which occurs as the groove velocity decreases.
• Turnover frequency:
  Same as transition frequency (which see).
• Vertical compliance:
  The ability of a reproducing stylus to move in a vertical direction while in the reproducing position on a record.
• Vertical recording (hill-and-dale recording):
  A recording wherein the groove modulation is in a plane tangent to the groove and normal to the surface of the record.
• Vertical stylus force: See stylus force.
• Wax:
  A blend of waxes with metallic soaps (also see cake wax).
• Wax master:
  A term improperly applied to a "wax original" (which see).
• William (or willy):
  A negative produced from a mother to produce still another mother.
• Wow:
  A low-frequency flutter (which see).

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