|  | G |
SECTION G — PHYSICS

INSTRUMENTS

|  | G10 |
MUSICAL INSTRUMENTS; ACOUSTICS

|  | G10 |
Note(s) This class covers generally all sound-emitting devices, whether or not they may be considered as being musical. The term "musical instrument", used in this class, should not be understood as excluding devices emitting a single sound signal. For the convenience of users, the following Class Index is given in place of Sub-class Indexes, to show the grouping of the elaborations belonging to different sub-classes, under the 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 these three types. They correspond to groups Fulltext... Hierarchy... Expanded...G10D 17/00 and Fulltext... Hierarchy... Expanded...G10K 7/00, Fulltext... Hierarchy... Expanded...G10K 9/00, Fulltext... Hierarchy... Expanded...G10K 10/00, all the other groups normally finding a definite place.

|  | G10L |
ANALYSIS OR SYNTHESIS OF SOUND WAVES; RECORDING WAVE-FORMS OF SOUND WAVES, e.g. SPEECH (measurement of mechanical vibrations Fulltext... Hierarchy... Expanded...G01H, e.g. Fulltext... Hierarchy... Expanded...G01H 3/00; electrophonic musical instruments Fulltext... Hierarchy... Expanded...G10H)

|  | G10L 1/00 |
Analysis or synthesis of sound waves, e.g. vocoder

|  | G10L 1/02 |
· | Derivation or interpretation of characteristics of sound waves

|  | G10L 1/04 |
· · | Detecting absence or presence of specific characteristics

|  | G10L 1/06 |
· | Removing redundancy of information contained in sound waves, e.g. to decrease frequency band required for transmission (Fulltext... Hierarchy... Expanded...G10L 1/10 takes precedence; modifications of systems to decrease bandwidth of signals in general Fulltext... Hierarchy... Expanded...H04B 1/66)

|  | G10L 1/08 |
· | Conversion of speech into digital information or vice versa

|  | G10L 1/10 |
· | Synthesis of sound waves using generators responding to characteristic wave-forms of sound, e.g. noise generator responding to whispering

|  | G10L 1/12 |
· | Recording or displaying of wave-forms of speech

|  | G10L 1/14 |
· · | by displaying on screen of cathode-ray tube

|  | G10L 1/16 |
· | Methods or arrangements for printing-out speech