DK44348C
(en )
1931-07-13
For sounding electromagnetic recording and reproduction of acoustic oscillations Steel sound carrier.
DK42949C
(en )
1930-09-15
Sound Carrier for Machines for Electromagnetic Recording of Acoustic Signs and Methods for Manufacturing the Same.
DK33968C
(en )
1924-12-22
Apparatus for apparatus for recording and reproducing phonographic sound waves.
DK42509C
(en )
1930-06-30
Acoustic Device for Receiving and Reproducing Sound.
DK46426C
(en )
1932-11-07
Device for Receiving and Reproducing Sound.
DK46385C
(en )
1932-10-31
Performance Film for Reproduction of Sound and Procedure for Recording Sound according to the Intensity Method.
DK42311C
(en )
1930-05-26
Device for uniform operation of the phonogram carrier when recording and reproducing sound films and the like.
DK47638C
(en )
1933-08-14
Device for sound recording and sound reproduction.
DK43097C
(en )
1930-10-06
Device for electrical vibration devices, in particular for the recording and reproduction of sound.
DK34877C
(en )
1925-08-17
Device for recording and reproducing sound.
FR655145A
(en )
1929-04-15
Sound reproducing diaphragm
FR668526A
(en )
1929-11-04
Advanced diaphragm for sound recording and reproducing devices
DK42626C
(en )
1930-07-21
Apparatus for recording and reproducing sound.
FR656235A
(en )
1929-04-30
Radiophonic receiver and amplifier of the vibrations transmitted by the electro-magnetic reproducers of phonographs
FR673659A
(en )
1930-01-17
Sound reproducer
FR660621A
(en )
1929-07-13
Development of sound reproducing diaphragms
ES106979A1
(en )
1928-06-16
Improvements in phonographic sound recording discs.
DK38775C
(en )
1928-05-21
Sound Reproducing Device (Speaker).
DK45620C
(en )
1932-05-02
Procedure and device for recording sound on a voice recorder or similar.
DK41598C
(en )
1930-02-10
Acoustic Device for Reproduction or Registration of Sound Waves.
ES109451A1
(en )
1928-10-16
Apparatus for the reproduction of photographs and sounds.
DK43632C
(en )
1931-01-26
Device for electromagnetic sound boxes for gramophones and the like.
FR648307A
(en )
1928-12-07
Acoustic case for amplifiers and sound recorders
DK48346C
(en )
1934-02-05
For sound recording and similar purposes determined Oscillograph.
DK38593C
(en )
1928-03-26
Sound Funnel or Speakers for Gramophones and Radios.