Patent Application
20160127818
The inventions covered in this application relate to Ear Buds, In Ear Monitors, Hearing Aids and all related personal listening devices (hereafter collectively referred to as “earbuds”).
More specifically, they relate to high fidelity earbud hearing protection and health while affording enhanced sound quality, isolation, fit, aesthetics, overall customizability characteristics, Bluetooth connectivity, the reduction of event-based hearing damage/noise pollution through their use at concerts, sports events, etc., live broadcast and location based syncing of at-event wireless audio streaming to smartphones and similar WiFi or Bluetooth devices,—as well as a novel displacement-based digital audio compression algorithm which electronically mitigates premature triggering of the acoustic reflex thereby allowing lower in-ear volumes to sound louder than conventional couplings which are known to cause hearing loss.
Earbuds provide utility as portable and private audio devices and are sometimes improperly employed to inadequately isolate the user from external sounds while listening to in/on-ear audio [U.S. Pat. Nos. 4,239,945; 4,742,887; 8,638,971B2]. Utilizing an ear tip, ear mold or ear cushion, earbuds partially or wholly seal the ear canal in an effort to increase the isolation from external sounds as well as increase the retention of both the device and the amplified sound within or around the ear. However, formal studies show their regular use leads directly to permanent hearing damage.
Large, high intensity transducer membrane excursions (ie. the vibratory back and forth movements of the speaker diaphragm) are necessary for the audible propagation of acoustic sound waves by earbuds. However, under partially or wholly sealed in-ear conditions, these relatively huge motions result in harmful oscillating pneumatic air pressures within the enclosed canal volume which overly impinge a significant percentage of the speaker diaphragm excursions directly onto the delicate and highly sensitive tympanic membrane, thereby overwhelming the natural compliance of the ear drum. Typical earbud/headphone speaker excursions range from microns to millimeters while normal tympanic membrane excursions range from only 100 to 250 nanometers, or roughly 1000 times smaller than typical speaker excursions.
Additionally, broadband, pneumatically coupled, in-ear sound pressures prematurely trigger the acoustic reflex, wherein, the tensor tympani muscle tightens the tympanic membrane, and the stapedius muscle pulls on and stiffens the ossicular chain, drawing the stapes away from the cochlea's oval window. This premature triggering often occurs as low as 60 dB when the ear canal is partially or wholly sealed instead of its typical audiologically established 88-90 dB threshold for an open ear canal.
Under these conditions, the net result of this premature triggering of the acoustic reflex is that sound waves are far less efficiently passed through to the inner ear, while their broadband pneumatic components continue to overly impinge on the tympanic membrane. Overall listening volumes are significantly less audible. The typical user response to this involuntary reflex is to turn the audio volume up much higher, resulting in international efforts to advise users of the dangers attendant upon listening to earbuds at excessive volume levels. This situation continues quite unresolved, resulting in habitual, overwhelming pressures on the tympanic membrane and leading to dramatic worldwide increases in permanent hearing loss.
The occlusion effect—i.e. bone conduction of one's own internal voice and body sounds resonating within the sealed ear canal (including transduction of external sound waves through vibrating bones, fluids, body cavities, tissues and in-ear devices) is the result of displacement based oscillating pneumatic air pressures from vibrating in ear surfaces which are then overly impinged onto both the tympanic membrane and the middle ear: sounds which are normally inaudible under unsealed conditions are pneumatically amplified as much as 1000 times (60 dB) over their normally unsealed volume levels. For example, one is able to easily hear the normally inaudible internal sounds of their own jaw motions or blood pumping amplified many times by simply plugging and sealing their ears with their fingers or foam ear plugs.
The confining of acoustically driven mechanical surface vibrations into relatively small, trapped volumes such as the ear canal results in unintended pneumatic displacement based in-ear acoustical amplifications similar to the intentional amplifications provided by stethoscopes, woodwinds, brass instruments, etc. All of these instruments gain their intended amplification through the principle of the pneumatic coupling of enclosed displacement based pneumatic pressures. This principle results in hearing loss when unwittingly applied to the ear because it is masked by the acoustic reflex and unrealized by the listener over time.
As described above, when the outer portion of the ear canal is sealed, in-ear sounds are significantly amplified by their aforementioned transformation into oscillatory pneumatic pressures, regardless of whether or not an active audio speaker is also present. However, this phenomena becomes greatly exaggerated when the normal diaphragm excursions of earbud speakers are introduced concurrent with mandibular (jawbone) deformations of the occluded ear canal walls such as those which occur during talking, singing, chewing, and yawning,—since all of these common physiological conditions independently create large increases in pneumatic in-ear pressures when the ear canal surfaces are exposed yet externally sealed and their accumulating pressures are thereby kept from immediately equalizing with normal external barometric pressure.
When earbuds conventionally seal the ear canal, these physiological conditions compound with transducer based in-ear sound pressures and together, dramatically increase the overall oscillating pneumatic pressure on the tympanic membrane by as much as 1 kPa or more. As already observed, this condition prematurely triggers the acoustic reflex, thereby demanding excessive listening volumes leading to hearing loss.
Conventional solutions to reducing the occlusion effect while wearing earbuds involve the introduction of leaks or vents into the chamber in front of the speaker. These leaks are acoustic as well as pneumatic and result in reduced volume levels, degraded bass frequency response and inadequate isolation and thereby demand higher listening volumes since the speaker is now driving a greatly enlarged or even unenclosed chamber. Here again, the typical user response has been to resort to excessive listening volumes. Unavoidable, accidental improved sealing conditions such as occur when shoving the device in deeper or leaning the ear containing the earbud up against a pillow or headrest often results in extremely high volumes which create pain and hearing loss before the person can easily respond, since the acoustic reflex greatly masks the condition.
Additionally, many conventional acoustic ear-coupling approaches use a hard, smooth surface for the ear tip or ear mold. Under conditions of mandibular deformation, such a surface forms an inconsistent seal, thus an intermittent leak between the coupler and the ear canal is inevitable, resulting in inconsistent coupling, degraded sound quality and inadequate isolation.
Some earbud designs utilize screened airflow channels independent of ear tip design to vent the front chamber air within the speaker housing to the outside, barometric pressure air. The Apple earbud design of 2013, for example, incorporates both venting methods [U.S. Pat. No. D691,594S] of the screened airflow channels and the hard, smooth ear tip surface. As described above, these solutions demand increased listening volumes.
Under wholly or partially sealed conditions, pneumatic pressures impede the motion of an earbud speaker. As the speaker moves within a sealed chamber, it inadvertently and variably compresses the trapped air into a smaller volume. As air is semi-incompressible, it resists, preventing the speaker from performing its intended linear excursion. Unlike unsealed conditions, the pressures created are nonlinear. Thusly impeded, the speaker exhibits slower transient responses, generating muddled, damped, lower quality sounds, which are especially nonlinear in the bass frequencies. Additionally, the natural performance of the Helmholtz resonance of the ear canal is significantly degraded.
In contrast, small air vents or screens are routinely employed in the back chamber of earbud speakers to allow similarly compressed air to escape and new air to flow in during rarefactions, thereby allowing the speaker to move more freely.
Under sealed conditions, the premature triggering of the acoustic reflex results in the stiffened compliance of the tympanic membrane variably determining the level of impedance on the speaker diaphragm facing the ear canal chamber, contributing significantly to the nonlinear functioning of both the speaker diaphragm and the tympanic membrane and thereby further degrading audio performance.
The aforementioned open-air pressure vents and leaks also act as acoustic vents. Employed in the chamber comprising the ear canal, sound amplitude and quality, particularly in the lower spectral regions, is significantly reduced with their use and listeners once again choose high audio volumes to recover the signal.
The Ambrose Diaphonic Ear Lens (ADEL) In-Ear Bubble invented by Stephen Ambrose (U.S. Pat. Nos. 8,340,310 B2 and 8,391,534 B2) significantly mitigates the shortcomings of conventional coupling systems such as common ear molds and ear tips. The inflatable ADEL ear tip is made of a highly flexible material, which when inflated, forms an effective, consistent and comfortable acoustic seal with the ear canal, despite physical exercise and mandibular deformations. The pressure exerted on the ear canal is sufficiently minimal that the presence of an ADEL disappears from the user's perception.
The ADEL is more compliant than the tympanic membrane by several orders of magnitude and is able to both absorb pneumatic pressures from within the sealed canal and reflect a greatly reduced return wave back onto the tympanic membrane. Unwanted reflections and resonances are substantially reduced.
The extremely low mass, low impedance mechanical excursion response of the ADEL membrane is much faster than both the speaker diaphragm and the tympanic membrane and results in ideal (extremely fast and high resolution) in-ear frequency/transient/dynamic range response—therefore significantly improving the performance and sound quality of any speaker mechanically coupled to the ear.
The inflatable ADEL very easily and comfortably enters, fills and displaces the full volume of the ear canal and thereby significantly reduces the occlusion effect. The tympanic membrane receives a more natural and healthy level of sound, the stapedius reflex does not prematurely trigger, the occlusion effect is minimized or removed, and the user perceives a much improved quality of sound throughout their listening experience without having to resort to excessive sound levels.
The passive, un-inflated ADEL absorbs the aforementioned pneumatic components of enclosed in-ear sound waves and thereby effectively lessens the occlusion effect as well as all the other unwanted conditions described above.
Many earbuds on the market are advertised as providing sound isolation. The isolation from exterior sounds is achieved by sealing the ear with unattractive, uncomfortable and noncompliant ear molds or over-sized foam or mushroom-shaped ear tips or with moldable materials such as self-curing silicones or wax.
In addition to being uncomfortable, conventional coupling methods often become dislodged, variably leak or introduce the occlusion effect (the unwanted booming bass of one's own voice), provide inadequate and inconsistent isolation/acoustic sealing and degrade the quality of in-ear acoustics by damping, exaggerating, muffling and blurring the source sound. Dedicated, sound isolating earbuds also operate under an all-or-nothing premise. The user must dislodge them to hear external sounds and replace them to hear the speaker and block off external sound.
Most available earbuds fit their users poorly and uncomfortably and their aesthetics tend to come at sacrifices to other earbud qualities. The diameter of the coupling element inserted into the ear may be too small or large, the element may be too short or angled incorrectly to match the user's ear topology. Ear couplers may be designed to be intentionally too large such as the foam plug or mushroom-cap tips to create a more complete seal and to resist falling out with motion. The oversized ear tips place a high pressure against the ear canal flesh and quickly become uncomfortable. Some models are designed with uncomfortable, non-customizable stabilizers or ear hangars in an attempt to take the weight of the earbud off the ear canal and improve stability; users commonly choose from a range of differently sized foam or mushroom-cap ear tips. Modifications of the length, direction, and curvature of the ear tips or overall custom fits are not available options to the general earbud consumer. While many earbuds are advertised as providing sound isolation, none are marketed for their ability to provide the user environmental awareness, and further none provide directionality-sensitivity. This creates a safety problem wherein the user is unable to hear warning sounds, other people, or other audible indications of impending harm.
The original in-ear monitor (IEM) invented by Stephen Ambrose in the 1960's and used for performances by musicians was the precursor for modern earbuds. IEMs tend to have customized, molded couplers that exactly fit performers' ears to attain the highest degree of isolation. These IEMs are uncomfortable in as much as the ear mold materials are rigid, fit tightly and do not flex with normal jaw motions; create very high levels of occlusion; and are unattractive as they tend to fill the visible ear canal with a vaguely flesh-colored plastic or silicon. An early version of Mr. Ambrose's IEM functioned as a portable listening device, a hearing aid and as functional jewelry [U.S. Pat. No. 4,852,177; 1989]. It employed a secondary acoustic path that vented pressures on the ear to a correct location in the earphone and prohibited a feedback cycle with the microphone that passed environmental sound into the sealed ear. These IEMs contributed less to hearing loss through this patented method by partially mitigating the pneumatic effects of sound constrained within the relatively small, trapped volumes of the sealed ear canal.
Most components that comprise conventional earbuds, whether they are custom-made or commercial, off-the-shelf products are not modifiable by the user. The user must choose at the time of purchase the set of earbud appearance, fit, quality and sound isolation that they are able to buy. Any desired variations require the purchase of another pair of earbuds.
Current Bluetooth connected earbuds are limited in both power and resolution. Bluetooth technology passes a low-resolution, compressed, digitized signal that degrades both the temporal resolution and the dynamic range of streamed music. Its receiver system can be a heavy user of power that requires frequent recharging. Many manufacturers opt to use a lower power version to minimize user frustrations but that comes at the cost of even less power for speaker operations. Speakers are then chosen that can only operate within remaining power budget, which further reduces the potential dynamic range of music.
Sound pressure levels of amplified live musical performances are commonly set at excessive volumes in an effort to produce a sensational experience for attendees. Because of the need for the sound emanating from speakers placed at the front of the stage to be loud enough to reach audiences in the back of the venue, attendees located closer to the stage are often subjected to deafening volumes for many hours. Such overstimulation triggers TTS (Temporary Threshold Shift wherein the listener's hearing sensitivity is involuntarily reduced) amongst the attendees, which then demands louder volumes to create the same sensation.
A resultant cacophony of competing sound sources further escalates these amplified sound pressure levels. In addition to highly amplified stage volumes, crowd noise, pyro technical explosions, etc., concert-goers also experience significant levels of physically transduced sounds (vibrations that impact and pass through the body).
These competing sound sources reflect off the walls, ceilings or other surfaces containing or surrounding the venue. In an attempt to cut through this confusion, amplified volumes are often pushed even louder.
In Ear Monitors were invented by Stephen Ambrose in 1965 and developed in the 70s with the help of Stevie Wonder to allow performers to hear their own music on stage and isolate away the competing sounds with the same quality they enjoy when using headphones in recording studios.
However, because these devices can create pneumatic pressures which trigger the acoustic or stapedius reflex and add the booming occlusion affect one's voice and music, they tend to subject the performers to excessive in-ear volume levels and must be dislodged or removed in order to hear ambient sounds. They are usually embodied in ear molds, which are uncomfortable and look unattractive. The isolation they offer is not optimum for all situations.
Auditory damage to both the performer's and the attendee's hearing caused by excessive volumes at musical events is well understood and documented. Civic regulations on noise pollution, timings and locations of events are continuing to limit venue opportunities for hosting a full-featured musical performance.
Currently available earbuds have limited ability to mitigate the excessive noise levels of amplified musical events. On the contrary, they tend to add their own inherently excessive listening levels to the excessive volumes present at the amplified even, thereby compounding the risk of hearing loss.
Conventional hearing protectors muffle the sound, are uncomfortable and can create excessive in-ear pressures. Additionally, occupants of areas neighboring a venue cannot practically or ethically be required to wear hearing protection devices.
Conventional in ear monitors do not allow an adjustable mixture of both the ambient and the electronically broadcast renditions of their performance. Often performers can be seen wearing only one IEM or hanging the other over their shoulder in order to hear their surrounding environment.
When worn out in the audience, IEMs sound far better than the over-amplified concert despite not being synchronized with the amplified sound coming off the stage. However, the further one is from the stage, the greater the lag between the broadcast sound and the amplified sound emanating from the stage speakers.
The capability of synchronizing these two sound sources and allowing for user-adjustable volumes and mixtures between the two (as allowed by the novel invention described herein) has not been possible before now.
Prior attempts at broadcast performances used a single broadcast source using radio transmissions and timing delays were incurred by the difference in the speed of sound (live music) versus the speed of light (radio transmissions). In a large enough venue, attendees receive the radio transmission before the live music reached them, which creates an untenable timing gap.
Conventional earbuds degrade and muffle the amplified concert sound as well as the broadcast in-ear speaker sound due to occlusion, speaker impedance mismatch with the tympanic membrane and the aforementioned and resultant over-stimulation of the acoustic reflex. This creates a disruptive quality gap when trying to simultaneously listen to a broadcast and a live performance. Excessive volumes of both audio sources are additive and the risk of hearing loss is increased even further.
Amplitude-based compression algorithms that limit the dynamic (soft to loud) range of sounds produced from an audio system are commonly available. One example applies to television ads. The creators or broadcasters of television advertisements often use amplitude based dynamic range compression to set the overall audio volume of their advertisements at a higher level than the programs within which they're aired to draw viewers' attention to them. Counteracting software exists that reduces those sound volumes back in line with the programs. Similar sound reduction software algorithms, which are generally known as digital dynamic range compression, are applied to audio systems, MP3 players and smartphones for listening to music more safely.
These existing algorithms are amplitude-based and are set at ratios of sound level volumes relative to the threshold of the maximum volume level that the manufacturer deems safe or the listener chooses to hear.
Problems arise from the variation in the efficiency of sound transmission and hearing sensitivity across the audible frequency range. Bass sounds displace much more air than mid-range sounds to produce the same apparent loudness to the listener (
In conclusion, no conventional earbud design to date is able to satisfactorily
Likewise, no existing in-ear-monitor
The invention, an improved earbud, has a fully modular set of parts that of primary importance includes membranes and variable vents which protect the listener's hearing while improving the quality and isolation of sound according to the user's desired characteristics whether wired or wireless and through its modularity, can achieve a uniquely personal fit and act as a visual vehicle of personal statement as well as drastically diminish the noise pollution of musical events and works with an improved, displacement-based digital compression algorithm. The membranes described herein may be a flexible compliant member as described in U.S. Pat. No. 8,744,435, the entire content of which is hereby incorporated by reference.
The variable vents, the membranes and speakers all dilute harmful pneumatic pressures off the eardrum and the speaker while the membranes maintain an acoustic seal necessary for the highest fidelity sound. A user can create their desired sound profile through end cap, speaker and filter hardware as well as venting configuration choices. A user can adjust for ambient sounds and achieve directionality-sensitivity of environmental audio signals through a second embodiment of the Ambrose Earbud.
The invention can be used in the passive mode (i.e. —the earbud is worn as normal in the ear but the speaker is not powered on) as a hearing protection device by closing the vents to the desired amount or similarly with an alternative and simpler embodiment, which has no speaker.
All parts of the improved earbud invention are fully modular and easily snap together and apart for easy assembly and user-driven interchangeability to suit listener preferences. The cochlea of most humans is located behind the eyes, however, the external ear and ear canal pathway geometries vary wildly from person to person. The Ambrose Earbud parts have a range of shapes and sizes to create the perfect fit and all parts rotate without limit about their intersections enabling a user to choose the height and directionality of the ear horn fit with their ear as well as the weight balance, separation, and venting of the earbuds. Licensed end-cap customizers will be able to create versions that are visually unique such as high-end jewelry or political statements and have precisely defined acoustic resonance profiles.
The connectivity of the improved earbud will also be modular. User's can choose a traditionally corded version, a Bluetooth version with the Bluetooth receiver on a cord between the earbuds or a fully wireless model, which has the Bluetooth receiver within the earbud housing as an additional layer. User's can switch between the connectivity options by screwing the relevant cable in to or out from the bottom of the earbud housing, which also has a spring contact plate. With the fully wireless options, user's can screw in an antenna that curls around the outer ear, improves the stability and range of the Bluetooth signal and acts as an earbud stabilizer. Connectivity through the audio cable provides the highest quality sound and the lowest price but many users find cables to be cumbersome as they are easily tangled and caught. The Ambrose earbuds will have high quality speakers at even the entry level despite power and resolution limits presented by Bluetooth connectivity. With better speakers than are normally paired to Bluetooth receivers, the sound quality passed to the user becomes the maximum possible with Bluetooth rather than further diminished. The Bluetooth receiver fob on the cable that only connects to the earbuds provides a mid-level dynamic range to the sound quality and cost to the user as the fob can hold a larger battery and thus provides a higher power budget for both the signal and speaker. While the earbud to earbud cable is less cumbersome than the traditional audio cable, many users desire a fully wireless design. The fully wireless design provides a maximum of physical freedom to the user and, with the entirety of the Ambrose Earbud technology, will provide the highest sound quality and dynamic range of any available Bluetooth earbud.
The Ambrose Earbud is the key element in reducing music performance sound levels while maintaining the high quality sensory experience of attendance.
Musical events will be restructured to separate the transduced and acoustic effects of loud sound through vibration projection and the broadcasting of an event's music to Ambrose Earbud-connected audio devices. Infrasound frequencies (those with frequencies below standard human hearing) will be projected against venue walls and into the attending crowd to create the transduced vibrations that energize an audience.
The performed music will not be amplified but instead be broadcast to each audience member's portable music device such as a music-enabled mobile phone. The attendee will connect to the venue's broadcast system and the broadcast sound will be synchronized to the live sound via a number of possible methods. By keeping track of an attendee's location, the broadcast system can control the release timing of a signal to their device to match the arrival of the live sound. A position-based delayed sound will keep track of the attendee's location through such methods as Global Positioning System (GPS), Wi-Fi triangulation, or user-indicated seat position. An application-based synchronization will quickly compare the arrival time of the live sound detected by the user's device microphone and generate the necessary time delay for the broadcast sound. The synchronization program can continuously correct the offset for an attendee that is moving through a venue. The broadcast sound will be processed according to the timing delay and optionally, the geometric acoustic response of the venue at that location. The shapes and materials of the walls, ceiling, floor and other structural elements all reflect and slightly alter the music in unique ways so that the music in one location, a corner for example, sounds notably different from that in the center of the main open space.
The attendee will be wearing the Ambrose Earbud and listening to their own, user-specific broadcast sound. The sound quality will not be diminished because the membranes respond quickly and uniformly to all frequencies, which maintains the crispness and precise tones of the performance. Performers will be listening to the Ambrose Earbud embodiment of in-ear monitors modified with the Ambrose Tunable Impedance-Matching Acoustic Transformer for the human ears based on bio-mimicry. Performers will be able to select their desired isolation or passage of ambient sound through the Transformer's secondary Eustachian tube. An ADEL membrane, as in other embodiments, acts as a second tympanic membrane and damps both external and streamed sounds, which can optionally be a broadcast of their own music at any location within the venue. Performer personalities, special effects and the shared energy of a crowd will still complete the musical event experience, sound quality and hearing safety will be improved and noise pollution minimized.
A displacement-based digital compression algorithm places a cap on sound output at a given frequency that is consistent with both the maximum safe air displacement within a sealed ear canal and the comfortable maximum loudness (in phons) for that frequency. When used in conjunction with an Ambrose Earbud, sound quality is maintained at all frequencies because the membrane responds uniformly well across the spectrum.
The advantages of the invention are to provide a safer and higher quality listening and sound isolation experience, ambient sound perception, improved comfort, and the new ability to fully customize the sound, fit and aesthetics of an earbud as well as the ability to remove excess sound levels from live music events while improving the listening experience and to process the sound output with a digital compression algorithm that is displacement-and-loudness-based per frequency to further protect listener hearing health. The anticipated usage of the Ambrose Earbud includes listening to personal audio devices such as music players and telephones; in loud environments where a reduced but clear sound is desired such as at a rock concert; and for situations that require total sound isolation such as while operating a jackhammer or for musicians while performing on stage.
The ear tip 5 snaps into the ear horn 4 which snaps into the front end cap 3. The ear horn 4 rotates about its intersection with the front end cap 3 and the end cap 3 rotates relative to the central control unit 2 to attain the user's desired ear horn position. The ear horn 4 is formed of a firm material such as a hard plastic and is not intended to be visible, however, a user can choose to customize its appearance. The ear horn 4 is shown in
The front end cap 3 snaps into the central control unit 2 which then snaps into the back end cap 1 and the interior volume of these three parts contain the parts depicted subsequently in
In
(1) A full seal provides isolation from exterior sounds for the user with a passive speaker. An active speaker will experience a high degree of impedance as it is trying to compress the initial volume of air into a smaller amount of space. The speaker will move slowly and not as far as it is directed to do by the power signal at audio cable 7. This reduces and blurs all sounds the speaker is intended to produce but especially affects the perceived bass sounds as the tympanic membrane is least sensitive to low spectral sounds and requires the highest amplitudes to produce the same perceived sound level. The membrane can do little to minimize the pneumatic pressures as it is contained within the same pressure environment.
(2) When the back volume is vented to the front volume (mutual venting) and the earbud is passive, a user will achieve a similar isolation to when both volumes are sealed and not vented to each other. The benefit of mutual venting is that it reduces the occlusion effect. When occlusion sounds occur, the pneumatic pressures reflect off and transmit through the membranes and speaker (acting as a membrane while passive) and the pressures can oscillate between the back, front and ear canal volumes, diluting the strength of the pneumatic pressures with each membrane interaction. If the user chooses to power the speaker—listen to something—with mutual sealed venting, the speaker becomes directional and the sound emitted through the back volume cancels those emitted through the front volume.
(3) An indirect, partial venting of the back volume through the front volume provides more isolation from exterior sounds than the same amount of direct, partial venting. Likewise, the speaker's impedance is reduced a small amount on the backwards motion while more is reduced in the frontwards motion. Both the exterior and the active speaker's sounds are amplified in the mid and high frequencies because the volume that is open—the front membrane and end cap-enclosed space—is smaller than that of the back as well as due to the doppler effect of the speaker relative to the tympanic membrane, which makes approaching sounds higher pitched and receding sounds lower.
(4) A sealed back volume with an open front volume will produce the highest impedance on the active speaker's backward motion with the least on its forward motion. Exterior and active speaker sounds will be crisp and strong in the mid and high frequencies while quiet and muddled at the low end of the sound spectrum.
In
In
A parallel set of venting options exist for the front end cap 3 and the chamber enclosed by front membrane 19 with an additional set of pneumatic energy dilution, speaker impedance removal and isolation characteristics. The closed, open or partially open front venting choice reduce, strengthen or pass at an intermediate level the mid and high frequencies' clarity and strength. An open front vent provides the best individual stress relief for the tympanic membrane as the front membrane 19 is the most compliant surface within the ear canal volume. When both the back and front vents 12 are open, the pneumatic pressures created by the active speaker's acoustic signals are reduced the most through the pressure impedances of each vent, membrane and the speaker, maximally relieving the tympanic membrane of pneumatic stresses.
From left, the back end cap 1 has a vent 12 and contains the back membrane 13 frame. The back membrane 11 rests inside the back membrane frame 13. The back membrane gasket 14 fits snugly inside the back membrane frame 13 and secures the back membrane 11 in place. The back membrane 11 acts as a sealed dividing wall to create a back chamber with the back end cap 1 and an ear canal chamber with the ear canal, tympanic membrane and the 19 front membrane 19. The back membrane 11 dilutes pneumatic pressures, provides an acoustic seal and maintains crisp, clear sound quality.
The back membrane-to-speaker spacer 15 and speaker frame rests against the back membrane frame 13. The back spacer-frame 15 holds the speaker in the correct location 21 and has an open notch to allow the audio cable 7 to pass through, connect and power the speaker. The speaker front gasket 16 secures the speaker's position and is contained within the back spacer-frame 15. The back spacer-frame 15 sits inside the central control unit 2 and fills most of its depth. The speaker front spacer 17 reinforces the speaker's position 21 and also sits inside the central control unit 2, filling the rest of its depth.
The front membrane-to-speaker frame 18 fits inside the front end cap 3 and has an orifice that allows sound to pass from the speaker, through the intersection orifice 22 of the front end cap 3 with the ear horn 4, the ear horn 4 itself, the ear tip 5, and the ear canal to finally reach the tympanic membrane. The front membrane 19 rests inside the front membrane-to-speaker frame 18 across the membrane orifice depicted as a bean shape. The front membrane-to-end cap frame 20 fits snugly inside the membrane orifice and secures the front membrane 19. The front end cap 3 has cavities to receive pins on the front membrane-to-speaker frame 18 that secure the two elements together in an orientation that enables the front membrane 19 to form a pneumatic pressure release chamber with the front end cap 3 with access to its variable vent 12. As with the back membrane 11, the front membrane 19 dilutes pneumatic pressures, provides an acoustic seal and maintains crisp, clear sound quality.
At the intersection 22 between the front end cap 3 and the ear horn 4, a metal mesh disk can be placed, which is used to filter pitches according to the user's preference. Smaller mesh spacings of a typical rectilinear pattern preferentially pass higher pitched sounds and larger spacings, lower frequency sounds. Customized sound filter disks can have a mixture of spacing sizes and shapes not limited to rectilinear patterns that provide a more nuanced filtering function across the sound spectrum.
Not shown in
All embodiments of the Ambrose Earbud are designed to be fully modular. Intersection edges have a ridge and a groove or are smoothly pressure-fitted. Adjacent parts are fitted together by aligning them and manually applying compression. The ridges of the two parts push up and over each other and land in the opposing part's groove. This style of part pairing provides simple and adhesive-free assembly as well as the ability for users and retail customizers to service and exchange parts without the need to purchase a new earbud. The snap-together connection is stable under typical use and snaps apart with reverse pressure.
During the manufacturer's assembly of the A1, employees prepare each end cap, stack the central elements and finish by connecting the end cap sections to the central section. The back membrane is placed within the back membrane frame and the back membrane gasket is pressed over the membrane, holding it fixed in place. The back membrane frame assembly is pressed into the back end cap. Likewise, the front membrane is placed across its designated orifice within the front membrane frame and the front membrane gasket is pressed over top, fixing it in place. The pins of the front membrane frame are placed and pressed into a set of holes on the front end cap, ensuring proper alignment and seal between the front membrane and the front end cap vent channel. The ear horn is pressed into the front end cap and the ear tip onto the ear horn. The speaker is placed within the back membrane-to-speaker frame and spacer and positioned so that the speaker's power connector element is aligned with the notch in the frame. The back membrane-to-speaker frame and spacer is placed inside the central control unit so that the notch is aligned with the cable port. The audio cable tip is passed through the cable port and situated so that the tip's pressure pins rest in their designated grooves in the cable port for proper mating with the speaker. The speaker front gasket is placed within the central control unit on the far side of the notch, after which, the speaker front spacer follows suit. The back end cap section is snapped onto the central control unit and likewise, the front end cap section.
During the manufacturer's assembly of the A2, employees begin with the side vent, exterior basket and fill it with each consecutive element moving outward from the ear (side vent, interior basket; ADEL membrane; transducers and their positioners; the top venting baskets; and the logo endcap). The cable connection assembly is then completed and finally the ear horn and tip.
During the manufacturer's assembly of the A3, employees begin with the controller and its stem. The ambient vent is screwed onto the stem and then the adjustable valve tube is placed around the stem. The controller stem base is snap-fitted into the center of the membrane tensioner and the pair is screwed onto the stem below the adjustable valve. The adjustable secondary Eustachian tube is coaxially placed around the stem and pressure-fitted onto the ambient vent. The ADEL membrane is stretched across the membrane frame and is held firmly in place by the pressure-fit between the membrane frame and the adjustable secondary Eustachian tube.
The user selects their preferred audio connectivity method: via audio cable, cabled Bluetooth, or fully wireless Bluetooth with or without the antenna stabilizer option. The audio cable, Bluetooth cable, and antenna stabilizer each are screwed into the cable jack of the earbud. At the terminus of the cable jack, there is a spring-plate connector across which signal from either cable or antenna is passed. The headphone jack is physically inserted into the user's audio device while the Bluetooth cable receiver or in-earbud receiver is wirelessly paired to the audio device. The user curls and crimps the antenna over their ear.
The user fits either Ambrose Earbud to their own ear geometry and preferred wearing method. The ear horn is first placed into the ear canal and rotated to the most comfortable direction. The front end cap of the A1 is then rotated about with the ear horn maintained in same relative direction to the ear canal to find the appropriate height of entry into the ear canal. With the simpler geometry of the A2 relative to the human ear, the user chooses just the relative angle of the audio cable, if used, to the ear horn. The user then chooses whether they prefer the cable to hang downward or to follow the optional ear hangar over the ear. A user determines through the exchange of ear horn models (described below) and trial and error, which set of ear horn length, curvature, direction and initial height creates the most comfortable fit for their ears.
For the standard earbud use-case of listening to music with no concerns of environmental sounds, the variable vents are open to the barometric air pressure (the A1 end caps are rotated so that the preferred fit is maintained) providing the greatest freedom of movement to the speaker as well as pneumatic pressure dilution away from the tympanic membrane. Venting variations can be used to process the sound according to the user's preference with the A1. The front vent is rotated to a less open to fully closed position to highlight bass sounds and in reverse, a less open back vent highlights mid to high pitches. The spectral processing of the A2 is conducted through programming of the set of transducers. Often, a user is expected to desire a nuanced, intermediate combination of sound isolation while actively listening through their Ambrose Earbuds. A user may be in a loud environment, such as on an airplane or in a noisy crowd, and want more isolation for their music or telephone conversation. To maintain the noiseless spectral characteristics of their audio source, both vents are reduced the same amount.
The Ambrose Earbud acts alternatively as a variable hearing protector. Maximum hearing protection from loud environmental sounds as well as internal occlusion effects is achieved with the speaker powered off. While maintaining the preferred fit, the user rotates the A1 end caps so that the variable vents are aligned through the vent channels on the central control unit to each other or by anti-aligning both sets of the A2 venting baskets. The user rotates the vents to partially open states to acquire partial isolation when they want to hear an external sound at a reduced level, such as while enjoying a rock concert, without sacrificing sound quality. As with an active speaker sound source, bass environmental sounds are highlighted by rotating the A1 front end cap to a reduced venting position and mid to high sounds, the back vent. Another alternative embodiment of the Ambrose Earbud is as a variable hearing protection device only. This embodiment would have no cable port or speaker yet would operate through manipulation of variable vents in a manner identical to the passive Ambrose Earbud acting as a hearing protector.
A user or retail customizer can service or exchange parts of either Ambrose Earbud. The earbud is opened and its internal parts accessed by placing finger tips or a small, strong object such as a penny between parts and exerting pressure against in an external direction. The earbud snaps open and the internal elements can be accessed. Thinner items such as finger nails or a miniature screwdriver are inserted between interior parts to similarly snap them apart. Worn parts are removed, replacements inserted and the earbud is snapped back together by realigning each element. Standard elements are replaced by preferred elements such as higher quality speakers; a denser and conical-bell shaped back A1 end cap for a specific resonance effect; a pair of precious inlayed metal end caps designed by renowned jeweler to highlight a special event; a longer and more curved ear horn for improved fit; etc. A sound filter is not standard but can be snapped into the ear horn during servicing. Once the servicing with all replacements or exchanges made is complete, the user re-assembles the parts and closes the earbud in the same manner as the original manufacturer.
A performer using the Ambrose Tunable Impedance-Matching Acoustic Transformer (A3) rotates the controller outward to reduce and inward to increase the amount of ambient sounds that they can hear. At an intermediate position, they hear some amount of their environmental sounds that is less than available with a fully open ear. The ADEL membrane experiences the least impedance as it is unrestrained by the membrane tensioner and the adjustable secondary Eustachian tube is vented to barometric pressure. Excess pneumatic pressures from sound are readily damped. At the innermost position, the membrane tensioner is in contact with the ADEL membrane and causes its impedance to increase. The membrane's impedance is proportional to the amount of tension placed upon it and has spectral properties. A performer can choose a small or large amount of tension to acquire their desired frequency processing affect. At the outermost position, the adjustable secondary Eustachian tube is isolated from ambient sounds and barometric pressure. The ADEL membrane is not physically tensioned yet it still experiences a high impedance since pressure changes cannot be vented. As with the tensioned membrane, when the adjustable valve is near its maximum diameter, frequency changes can be heard by the performer and controlled to their desired properties. When the ADEL membrane is at its maximum impedance, whether through a sealed vent or through tensioning, the speaker necessarily also experiences maximum impedance. Since pneumatic pressures are not damped via the membrane, they impinge back into the sealed ear canal and impact both the tympanic membrane and the speaker. The reverse is also true. The speaker experiences minimum impedance when the ADEL membrane is most free to flex and dampen the pneumatic pressures of sound.
At music performances with noise-reducing broadcast systems, music is performed on stage with no amplification and microphones pick up the sounds. Attendees sign into the broadcast system with their music devices and select either a location-based delay using methods such as GPS, Wi-Fi or seat numbers or a sound-synchronization method that employs their own device's microphone to detect the live music and calculate a timing offset for the broadcast transmission. The system broadcasts the music to the attendee's audio device delayed by their distance from the performers and modulated by the geometry of the venue in the attendee's instantaneous location. The broadcast signal is passed to the attendee's Ambrose Earbuds, which are adjusted according to the attendee's preferences and as indicated above. Infrasounds, lights, smoke, and other special effects are manipulated to generate energy in the audience and create a unique listening event experience. Performers also sign into the broadcast system and monitor the sound the audience hears by choosing the broadcasts for specific locations across the venue.
A displacement-and-loudness-based digital compression algorithm is integrated into audio processing software such as a music application on a smartphone. The user chooses whether or not to have the digital compression on and, if on, which type of ear tip they are using as each ear tip type has a corresponding upper limit on air displacement from sound before hearing damage can occur. Among ear tips that seal the ear canal, such as foam plugs or mushroom-cap styles, the Ambrose Earbud negates the greatest amount of damage yet requires the least amount of sound volume for a quality listening experience. The user also selects the minimum sound volume across the spectrum and therefore, creates their own customized dynamic range. As each note of music passes through the audio processing software, the digital compression algorithm raises a too quiet pitch to the user's minimum and reduces an overly loud pitch to the maximum volume according to how much air is displaced at its' frequency and the energy dilution of the user's ear tip. The musical note is then passed from the audio processing software to the listener's ear.
The present application claims the benefit of U.S. Provisional Application No. 62/075,107, filed Nov. 4, 2014, the complete content of which is hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62075107 | Nov 2014 | US |
