|  | G |
SECTION G — PHYSICS

|  | G |
Note(s) In this section, the following term is used with the meaning indicated: "variable" (as a noun) means a feature or property (e.g., a dimension, a physical condition such as temperature, a quality such as density or colour) which, in respect of a particular entity (e.g., an object, a quantity of a substance, a beam of light) and at a particular instant, is capable of being measured; the variable may change, so that its numerical expression may assume different values at different times, in different conditions or in individual cases, but may be constant in respect of a particular entity in certain conditions or for practical purposes (e.g., the length of a bar may be regarded as constant for many purposes). Attention is drawn to the definitions of terms or expressions used, appearing in the notes of several of the classes in this section, in particular those of "measuring" in class Fulltext... Hierarchy... Expanded...G01 and "control" and "regulation" in class Fulltext... Hierarchy... Expanded...G05. Classification in this section may present more difficulty than in other sections, because the distinction between different fields of use rests to a considerable extent on differences in the intention of the user rather than on any constructional differences or differences in the manner of use, and because the subjects dealt with are often in effect systems or combinations, which have features or parts in common, rather than "things", which are readily distinguishable as a whole. For example, information (e.g., a set of figures) may be displayed for the purpose of education or advertising (Fulltext... Hierarchy... Expanded...G09), for enabling the result of a measurement to be known (Fulltext... Hierarchy... Expanded...G01), for signalling the information to a distant point or for giving information which has been signalled from a distant point (Fulltext... Hierarchy... Expanded...G08). The words used to describe the purpose depend on features that may be irrelevant to the form of the apparatus concerned, for example, such features as the desired effect on the person who sees the display, or whether the display is controlled from a remote point. Again, a device which responds to some change in a condition, e.g., in the pressure of a fluid, may be used, without modification of the device itself, to give information about the pressure (Fulltext... Hierarchy... Expanded...G01L) or about some other condition linked to the pressure (another subclass of class Fulltext... Hierarchy... Expanded...G01, e.g., Fulltext... Hierarchy... Expanded...G01K for temperature), to make a record of the pressure or of its occurrence (Fulltext... Hierarchy... Expanded...G07C), to give an alarm (Fulltext... Hierarchy... Expanded...G08B), or to control another apparatus (Fulltext... Hierarchy... Expanded...G05). The classification scheme is intended to enable things of a similar nature (as indicated above) to be classified together. It is therefore particularly necessary for the real nature of any technical subject to be decided before it can be properly classified.

INSTRUMENTS

|  | G10 |
MUSICAL INSTRUMENTS; ACOUSTICS

|  | G10 |
Note(s) This class covers all sound-emitting devices, in general, whether or not they may be considered as being musical. In this class, the following expression is used with the meaning indicated: "musical instrument" does not exclude devices emitting a single sound signal. The following Class Index is given in place of subclass indexes, to show the grouping of the elaborations belonging to different subclasses, under the following three fundamental types: wind instruments; string instruments; percussion instruments, which relate clearly to the majority of instruments. There are of course some instruments of which the principle of operation belongs less clearly to one of the three types mentioned in Note (3). They correspond to groups Fulltext... Hierarchy... Expanded...G10D 17/00 or Fulltext... Hierarchy... Expanded...G10K 7/00, Fulltext... Hierarchy... Expanded...G10K 9/00 or Fulltext... Hierarchy... Expanded...G10K 15/04, all the other groups normally finding a definite place.

|  | G10 |
Class index
ACOUSTICS; OPERATIONS ON SOUND WAVES |
Speech analysis or synthesis; speech recognition | G10L
Methods or devices for transmission of sound or protection against sound, not otherwise provided for | G10K 11/00, G10K 13/00
Acoustics not otherwise provided for | G10K 15/00
WIND INSTRUMENTS |
General features; details, accessories | G10D 7/00; G10D 9/00
Organs, harmoniums, or similar instruments | G10B 1/00, G10B 3/00
Accordions, concertinas, or similar instruments; other types of instruments | G10D 11/00; G10D 7/00
Whistles; sirens; horns | G10K 5/00; G10K 7/00; G10K 9/00
STRING INSTRUMENTS |
General features; details, accessories | G10D 1/00; G10D 3/00
Pianos, similar instruments; tools and methods for making or maintenance | G10C 1/00, G10C 3/00; G10C 9/00
Other types of instruments | G10D 1/00
PERCUSSION INSTRUMENTS |
Bells, rattles, or similar instruments | G10K 1/00, G10K 3/00
Other instruments | G10D 13/00
OTHER PARTICULAR DEVICES: DEVICES USING UNDEFINED PRINCIPLES; COMBINATIONS OF INSTRUMENTS; MUSIC ACCESSORIES |
Electrophonic musical instruments | G10H
Automatic musical instruments | G10F
Sirens; devices with vibrators | G10K 7/00; G10K 9/00
Combinations: of pianos with other instruments; of other instruments | G10C 5/00; G10D 15/00
Music accessories | G10G
INSTRUMENTS NOT OTHERWISE PROVIDED FOR | G10D 17/00

|  | G10H |
ELECTROPHONIC MUSICAL INSTRUMENTS (electronic circuits in general Fulltext... Hierarchy... Expanded...H03)

|  | G10H |
Note(s) This subclass covers musical instruments in which individual notes are constituted as electric oscillations under the control of a performer and the oscillations are converted to sound-vibrations by a loud-speaker or equivalent instrument.

|  | G10H 1/00 |
Details of electrophonic musical instruments (keyboards applicable also to other musical instruments Fulltext... Hierarchy... Expanded...G10B, Fulltext... Hierarchy... Expanded...G10C; arrangements for producing a reverberation or echo sound Fulltext... Hierarchy... Expanded...G10K 15/08) [5]

|  | G10H 1/02 |
· | Means for controlling the tone frequencies, e.g. attack, decay; Means for producing special musical effects, e.g. vibrato, glissando

|  | G10H 1/04 |
· · | by additional modulation

|  | G10H 1/043 |
· · · | Continuous modulation [3]

|  | G10H 1/045 |
· · · · | by electromechanical means [3]

|  | G10H 1/047 |
· · · · | by acousto-mechanical means, e.g. rotating speakers or sound deflectors [3]

|  | G10H 1/053 |
· · · | during execution only [3]

|  | G10H 1/055 |
· · · · | by switches with variable impedance elements [3]

|  | G10H 1/057 |
· · · · | by envelope-forming circuits [3]

|  | G10H 1/06 |
· · | Circuits for establishing the harmonic content of tones

|  | G10H 1/08 |
· · · | by combining tones (Fulltext... Hierarchy... Expanded...G10H 1/14, Fulltext... Hierarchy... Expanded...G10H 1/16 take precedence; chord Fulltext... Hierarchy... Expanded...G10H 1/38; speech analysis or synthesis, Fulltext... Hierarchy... Expanded...G10L) [3]

|  | G10H 1/10 |
· · · · | for obtaining chorus, celeste or ensemble effects (continuous modulation Fulltext... Hierarchy... Expanded...G10H 1/043) [3]

|  | G10H 1/12 |
· · · | by filtering complex wave forme (Fulltext... Hierarchy... Expanded...G10H 1/14, Fulltext... Hierarchy... Expanded...G10H 1/16 take precedence) [3]

|  | G10H 1/14 |
· · · | during execution (modulation during execution Fulltext... Hierarchy... Expanded...G10H 1/053) [3]

|  | G10H 1/16 |
· · · | by non-linear elements (Fulltext... Hierarchy... Expanded...G10H 1/14 takes precedence; generation of non-sinusoidal basic tones Fulltext... Hierarchy... Expanded...G10H 5/10) [3]

|  | G10H 1/18 |
· | Selecting circuits [3]

|  | G10H 1/20 |
· · | for transposition [3]

|  | G10H 1/22 |
· · | for suppressing tones; Preference networks [3]

|  | G10H 1/24 |
· · | for selecting plural preset register stops [3]

|  | G10H 1/26 |
· · | for automatically producing a series of tones [3]

|  | G10H 1/28 |
· · · | to produce arpeggios [3]

|  | G10H 1/30 |
· · · | to reiteratively sound two tones [3]

|  | G10H 1/32 |
· | Constructional details [3]

|  | G10H 1/34 |
· · | Switch arrangements, e.g. keyboards or mechanical switches peculiar to electrophonic musical instruments (keyboards applicable also to other musical instruments Fulltext... Hierarchy... Expanded...G10B, Fulltext... Hierarchy... Expanded...G10C) [3]

|  | G10H 1/36 |
· | Accompaniment arrangements [3]

|  | G10H 1/38 |
· · | Chord [3]

|  | G10H 1/40 |
· · | Rhythm (metronomes Fulltext... Hierarchy... Expanded...G04F 5/02) [3]

|  | G10H 1/42 |
· · · | comprising tone forming circuits [3]

|  | G10H 1/44 |
· | Tuning means [3]

|  | G10H 1/46 |
· | Volume control [3]

|  | G10H 3/00 |
Instruments in which the tones are generated by electromechanical means

|  | G10H 3/02 |
· | using mechanical interrupters

|  | G10H 3/03 |
· | using pick-up means for reading recorded waves, e.g. on rotating discs [3]

|  | G10H 3/06 |
· · | using photoelectric pick-up means

|  | G10H 3/08 |
· · | using inductive pick-up means

|  | G10H 3/09 |
· · · | using tapes or wires [3]

|  | G10H 3/10 |
· · | using capacitive pick-up means

|  | G10H 3/12 |
· | using mechanical resonant generators, e.g. strings or percussive instruments, the tones of which are picked up by electromechanical transducers, the electrical signals being further manipulated or amplified and subsequently converted to sound by a loudspeaker or equivalent instrument [3]

|  | G10H 3/14 |
· · | using mechanically actuated vibrators with pick-up means (Fulltext... Hierarchy... Expanded...G10H 3/24 takes precedence) [3]

|  | G10H 3/16 |
· · · | using a reed [3]

|  | G10H 3/18 |
· · · | using a string, e.g. electric guitar [3]

|  | G10H 3/20 |
· · · | using a tuning fork, rod or tube [3]

|  | G10H 3/22 |
· · | using electromechanically actuated vibrators with pick-up means (Fulltext... Hierarchy... Expanded...G10H 3/24 takes precedence) [3]

|  | G10H 3/24 |
· · | incorporating feedback means, e.g. acoustic [3]

|  | G10H 3/26 |
· · · | using electric feedback [3]

|  | G10H 5/00 |
Instruments in which the tones are generated by means of electronic generators (Fulltext... Hierarchy... Expanded...G10H 7/00 takes precedence) [3]

|  | G10H 5/02 |
· | using generation of basic tones

|  | G10H 5/04 |
· · | with semiconductor devices as active elements (Fulltext... Hierarchy... Expanded...G10H 5/10, Fulltext... Hierarchy... Expanded...G10H 5/12 take precedence)

|  | G10H 5/06 |
· · | tones generated by frequency multiplication or division of a basic tone

|  | G10H 5/07 |
· · · | resulting in complex waveforms [3]

|  | G10H 5/08 |
· · | tones generated by heterodyning

|  | G10H 5/10 |
· | using generation of non-sinusoidal basic tones, e.g. sawtooth

|  | G10H 5/12 |
· · | using semiconductor devices as active elements

|  | G10H 5/14 |
· | using electromechanical resonator, e.g. quartz crystal, as frequency-determining element [3]

|  | G10H 5/16 |
· | using cathode ray tube [3]

|  | G10H 7/00 |
Instruments in which the tones are synthesised from a data store, e.g. computer organs (synthesis of acoustic waves not specific to musical instruments Fulltext... Hierarchy... Expanded...G10K 15/02, Fulltext... Hierarchy... Expanded...G10L) [3,5]

|  | G10H 7/02 |
· | in which amplitudes at successive sample points of a tone waveform are stored in one or more memories [5]

|  | G10H 7/04 |
· · | in which amplitudes are read at varying rates, e.g. according to pitch [5]

|  | G10H 7/06 |
· · | in which amplitudes are read at a fixed rate, the read-out address varying stepwise by a given value, e.g. according to pitch [5]

|  | G10H 7/08 |
· | by calculating functions or polynomial approximations to evaluate amplitudes at successive sample points of a tone waveform [5]

|  | G10H 7/10 |
· · | using coefficients or parameters stored in a memory, e.g. Fourier coefficients (Fulltext... Hierarchy... Expanded...G10H 7/12 takes precedence) [5]

|  | G10H 7/12 |
· · | by means of a recursive algorithm using one or more sets of parameters stored in a memory and the calculated amplitudes of one or more preceding sample points [5]