FR638286A
(en )
1928-05-21
Sound reproducer
DK42509C
(en )
1930-06-30
Acoustic Device for Receiving and Reproducing Sound.
DK46426C
(en )
1932-11-07
Device for Receiving and Reproducing Sound.
DK38775C
(en )
1928-05-21
Sound Reproducing Device (Speaker).
FR616738A
(en )
1927-02-07
Loud speaker
DK34877C
(en )
1925-08-17
Device for recording and reproducing sound.
DK42626C
(en )
1930-07-21
Apparatus for recording and reproducing sound.
FR612462A
(en )
1926-10-25
Loud speaker
DK38593C
(en )
1928-03-26
Sound Funnel or Speakers for Gramophones and Radios.
AT112399B
(en )
1929-02-25
Sound recording and reproducing apparatus.
DK43097C
(en )
1930-10-06
Device for electrical vibration devices, in particular for the recording and reproduction of sound.
FR623776A
(en )
1927-06-30
Acoustic amplifier device for loudspeakers, phonographs, and similar apparatus
DK41677C
(en )
1930-02-17
Procedure and Device for Elimination of Vibrations.
DK36770C
(en )
1926-11-08
Device for sound boxes for gramophones and the like.
ES99108A1
(en )
1926-11-01
Improvements in sound devices for sound recorders and reproducers.
DK38776C
(en )
1928-05-21
Sound Reproducing Device (Speaker).
DK38638C
(en )
1928-04-02
Sound Reproducing Device (Speaker).
DK34490C
(en )
1925-05-11
Apparatus for Sending and Receiving Sound Waves.
DK40851C
(en )
1929-09-30
Cone-shaped Membrane for Speakers and the like.
DK38510C
(en )
1928-03-05
Sound reproducing apparatus.
DK41771C
(en )
1930-03-03
Procedure and Device for the Manufacture of Cigars.
FR617464A
(en )
1927-02-19
Loud speaker
DK40081C
(en )
1929-04-29
Tone amplifier for radios, gramophones and the like.
FR621496A
(en )
1927-05-12
Amplifier for telephone and phonograph sounds
DK42173C
(en )
1930-05-05
Vibration device for Microphones, Speakers and similar Devices.