HK1004511B - Dual element headphone - Google Patents

Description

Background of the Invention

This invention relates to headphones for sound reproduction with high fidelity, and in particular to dual element headphones having one transducer for each ear directed to reproducing higher frequencies and one transducer for each ear directed to reproducing lower frequencies.

Designers of loudspeakers have long recognized the need for more than a single acoustic transducer to faithfully reproduce the entire audio spectrum. Quality loudspeakers may contain from two to five separate acoustic transducers, each designed to operate over a specific portion of the audio spectrum. Crossover networks are employed to distribute the applied audio signal to the proper acoustic transducer and these typically include circuits comprised of resistors, capacitors and inductors.

In the same vein, headphones having two transducer elements for each side are known in the art. Refer particularly, for instance, to Piribauer, U.S. Patent No. 3,943,304, wherein there is disclosed a headphone speaker system which combines a dynamic transducer for lower frequencies with an electrostatic transducer for higher frequencies. Similarly, the disclosure of Mathis, U.S. Patent No. 4,418,248, shows use of two transducers, in this case using a dynamic transducer for lower frequencies and a piezoelectric transducer for higher frequencies. And Andre et al, U.S. Patent No. 4,965,836 discloses use of two dynamic transducers, a larger one for lower frequencies and a smaller one for higher frequencies. In each of the headphones disclosed in these patents, the transducers are oriented substantially coaxially, so that the sound from the two transducers emanates in almost entirely the same direction.

FR-A-2 547 152 discloses a headphone having one transducer for each side of the headphone. The transducer may be inserted in the cavum concha of a listener's ear.

This invention relates to improvements to the headphone and loudspeaker apparatus set forth above and to solutions to some of the problems raised or not solved thereby.

Summary of the Invention

The invention comprises a dual element headphone for use by a listener. The object of the invention is achieved by the features of claim 1. In a preferred embodiment means are provided for dividing the electrical signals received by the headphone, and transmitting signals for higher frequencies to the first, smaller transducer and signals for lower frequencies to the second, larger transducer. The supporting means would normally include a headband and mounting plate, providing a set of these transducers for association with each ear. The first transducer may be flexibly mounted to the supporting means for improved comfort and sound fidelity.

Other objects and advantages of the invention will become apparent hereinafter.

Description of the Drawing

Fig. 1 is a perspective view of a headphone constructed according to a preferred embodiment of the invention.

Fig. 2 is a side elevational view, partially in section, of the transducer assembly of the headphone shown in Fig. 1.

Fig. 3 is a front elevational view, partially in section, of the transducer assembly of the headphone shown in Fig. 1.

Fig. 4 is a top plan view, partially in section, of the smaller transducer, taken along line 4-4 of Fig. 2.

Fig. 5 is a side elevational view, partially cut away, of the transducer assembly of the headphone shown in Fig. 3 along line 5-5.

Fig. 6 is a cross sectional view, taken generally along line 6-6 of Fig. 3.

Description of the Preferred Embodiment

Referring now to Fig. 1, there is shown a headphone apparatus 10 constructed according to a preferred embodiment of the invention. The headphone 10 includes a headband 12, generally fitted over the head of a listener. To each end of headband 12 is attached a transducer assembly 14, by means of an earcup assembly 16.

As shown in Figs. 2, 3 and 6, according to the invention each transducer assembly 14 includes a large transducer 18, mounted by any suitable means to the earcup assembly 16. Generally such mounting means will include a mounting plate 20 to which large transducer 18 is attached. Since a portion of mounting plate 20 is positioned in front of transducer 18, the mounting plate is provided with slots 20a, to permit passage of sound therethrough. Large transducer 18 is of a size substantially larger than the cavum concha 22 of the listener's ear. Mounting plate 20 is connected to the headband so as to position itself and large transducer 18 substantially flat against the listener's auricle 24.

The invention also calls for another, smaller transducer 26 affixed within a housing 28. This housing 28 is associated with large transducer 18 so that sound emanates from the smaller transducer 26 in a direction transverse to the direction of the sound emanating from the large transducer. In the embodiment shown in the drawing figures, the housing 28 is attached to the mounting plate 20 and projects outwardly therefrom. As shown in Figs. 3 and 6, housing 28 projects substantially perpendicular to the mounting plate 20, and is sized so as to at least partially fit into the cavum concha 22 of the listener's ear. Housing 28 is larger in area, however, than the entrance of the external acoustic meatus 30 of the listener's ear. When in use by the listener, then, housing 28 projects into the cavum concha 22 and aligns the smaller transducer 26 generally with the entrance to the external acoustic meatus 30. With smaller transducer 26 thus positioned, the sound emanating therefrom is transmitted almost directly to the tympanum 32 of the listener's ear.

The invention also provides for conventional crossover filter means 34 (Fig. 4) for dividing the sound signal into lower frequencies and higher frequencies. By this means 34 the lower frequencies are transmitted to the larger transducer 18 while the higher frequencies are transmitted to the smaller transducer 26. Since the smaller transducer 26 is positioned almost directly facing the tympanum 32, the higher frequencies are transmitted to the tympanum with great fidelity. Correspondingly, since the larger transducer 18 is positioned further away from the tympanum 32, the relatively larger amplitudes of the lower frequencies are prevented from uncomfortably over-exercising the tympanum.

For greater comfort in using and wearing the headphone 10, it is known to provide padding material, such as foam pads 36, to cover the large transducer 18 and mounting plate 20. In the present invention, in order to further improve comfort in use, the mounting of the housing 28 to the mounting plate 20 may be a flexible mounting 38. This flexible mounting 38 includes a boot 40 attached to the plate 20, the other end of the boot easily carrying the relatively lightweight housing 28. The signals to the smaller transducer 26 should then be carried by some flexible means such as flexible wires 42 (Fig. 5) rather than some other means such as solid traces.

While the apparatus hereinbefore described is effectively adapted to fulfill the aforesaid objects, it is to be understood that the invention is not intended to be limited to the specific preferred embodiment of dual element headphone set forth above. Rather, it is to be taken as including all reasonable equivalents within the scope of the following claims.

Claims (9)

1. A headphone speaker system (10) comprising:

   a first acoustic transducer (26) for producing sound from electrical signals, said first transducer (26) being sized so as to fit into the cavum concha (22) of a listener's ear and arranged to direct the produced sound in a first predetermined direction; and

   a second acoustic transducer (18) for producing sound from electrical signals, said second transducer (18) being substantially larger than said first transducer (26) and arranged so as to substantially overly at least a portion of the auricle (24) of said listener's ear and arranged to direct sound in a second predetermined direction transverse to said first predetermined direction.
2. The system of claim 1 further comprising means (42) for receiving electrical signals to be converted to sound and means (24) for dividing said electrical signals and sending signals for higher frequencies to said first transducer (26) and sending signals for lower frequencies to said second transducer (18).
3. The system of claim 1 or 2, wherein said first acoustic transducer (26) is mounted to a mounting plate (20) by means of a flexible mounting (38).
4. The system of claim 3, wherein said first transducer (26) is positioned by said mounting plate (20) so as to direct sound into the external acoustic meatus (30) of said listener's ear.
5. The system of claim 3 or 4, further comprising a headband (12) connected to said mounting plate (20) for supporting said transducers (18, 26) in proximity to said listener's ear.
6. The system of claim 5, wherein said mounting plate (20) is connected at one end of said headband (12), said system further comprising another mounting plate (20) carrying a further first and a further second acoustic transducer (26, 18) according to claim 1 for association with the listener's other ear.
7. The system of claim 1 or 2, wherein said first acoustic transducer (26) is mounted within a first housing (28) being sized so as to at least partially fit into the cavum concha (22) of said listener's ear and being larger in area than the entrance of the external acoustic meatus (30) of said listener's ear, said second acoustic transducer (18) is mounted within a second housing (16) being substantially larger than said first housing (28), said system further comprising supporting means for supporting said first acoustic transducer (26) in said listener's ear so as to direct sound towards the entrance of said external acoustic meatus (30), wherein said second housing (16) is connected to said supporting means so as to overlie at least a portion of said auricle (24) of said listener's ear.
8. The system of claim 7, wherein said supporting means includes a headband (12) connected to said transducers (18, 26) for supporting said transducers in proximity to said listener's ear.
9. The system of claim 8, wherein said supporting means includes a-first mounting plate (20) connected at one end of said headband (12) and a second mounting plate (20) connected at the opposite end of said headband (12), said first mounting plate (20) carrying said first and second transducers (26, 18) and said second mounting plate carrying a further one of said first and a further one of said second transducers (26, 18) for association with said listener's other ear.