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APEquamm uses unique technology to rebuild this experience along with your audio devices. Using material acoustic, new material, analogue and digital audio technology, we rebuild natural sound from any digital media record.

By the pushing by the compact size requirement of mobility devices, a great step of improvement of the traditional magnetic coil speakers within the last few years. But the “1.5mm thickness of magnetic coil speaker” (refer to Panasonic Technical Paper Vol.54 No.4) magical number seems to be the limitation of nowadays technology. However, the necessary of acoustic enclosure of speaker obstructs the decreasing of the total thickness of devices.

The performance of bass of micro speaker also be limited by the origin theoretical condition of magnetic coil speaker structure.

APEquamm speakers are applied with brand new acoustic conceptual theories to overcome the “1.5mm thickness limitation” , “1.05mm or 1.25mm thickness smart-speaker” without necessary of extra acoustic enclosure are ready to ship.

Embedded with MEMs or ANC audio codec, the future portfolio of “smart-speaker combo or modules” will not just optimize the system structure, but also make complete change of acoustic system design of mobility devices.

Traditional Magnetic Coil Speakers

An enormous amount of engineering work has gone into the design of today's dynamic speaker. A light voice coil is mounted so that it can move freely inside the magnetic field of a strong permanent magnet. The speaker cone is attached to the voice coil and attached with a flexible mounting to the outer ring of the speaker support. Because there is a definite "home" or equilibrium position for the speaker cone and there is elasticity of the mounting structure, there is inevitably a free cone resonant frequency like that of a mass on a spring. The frequency can be determined by adjusting the mass and stiffness of the cone and voice coil, and it can be damped and broadened by the nature of the construction, but that natural mechanical frequency of vibration is always there and enhances the frequencies in the frequency range near resonance. The diameter, area and sharp of diaphragm are one of the key factors of the peaks on frequency response. Part of the role of a good enclosure is to minimize the impact of this resonant frequency. The characteristic of the magnetic coil speaker construction limits their miniaturization and thinness, those make the coil speaker can’t be fitted into the “as slim as possible device” and keeping the similar audio performance.

Electrostatic Speaker

The “Backwards condenser mic” is electrostatic speaker. It is a large and flat diaphragm between two oppositely charged plates plus polarity (+) and minus polarity (-), the electrical input alternates its charge and causing vibration. However, it is expensive and harder to manufacture, usually lacking in bass response, but there are high end products makers , such as Martin Logan and Quad have been overcome the issue.

 

Sound Vibration Transducer(Vibration Speaker)

A vibration speaker is similar, except that there's no diaphragm. Instead, the voice coil attaches to a movable plate. Setting a vibration speaker down on a solid surface positions the plate so that it will vibrate against that surface. As current alternates in the coil, it moves up and down, pushing against the movable plate. The plate pushes against the surface, transferring the energy to the surface and turning it into a speaker. Because vibration speakers convert electrical energy into mechanical energy, they are also known as transducers. A transducer is a device that can convert one form of energy into another.

The solid surface will vibrate with the speaker, displacing air molecules around it. Just as with any other sound, your ear detects the movements of the colliding air molecules. Some materials reverberate better than others -- not all solids are created equal. In general, glass and wood tend to work best with vibration speakers. You can even mount vibration speakers on the inside of a wall, leaving the speakers invisible to those in the room. Because the speakers transfer vibrations to the surfaces you mount them on, the wall itself will send out sound.

Reference:

a) http://hyperphysics.phy-astr.gsu.edu/hbase/audio/spk.html

b) http://www.nyu.edu/classes/bello/FMT_files/4_Loudspeaker.pdf

c) http://electronics.howstuffworks.com/gadgets/audio-music/vibration-speakers2.htm

d) Aperion Audio. "How Speakers Work." 2012. (April 11, 2012)

http://www.aperionaudio.com/AperionU/how_speakers_work.aspx

e) Elsea, Peter. "Sound." UCSC Electronic Music Studios. 1995. (April 11, 2012)

http://artsites.ucsc.edu/ems/music/tech_background/TE-01/teces_01.html

f) Gigabox. (April 11, 2012)

http://www.gigabox.co.uk/about-us/

g) Nave, R. "Organ of Corti." HyperPhysics. (April 11, 2012)

http://hyperphysics.phy-astr.gsu.edu/hbase/sound/corti.html#c1

h) Nave, R. "Speed of Sound in Various Bulk Media." HyperPhysics. (April 17, 2012)

http://hyperphysics.phy-astr.gsu.edu/hbase/tables/soundv.html

i) Shuttleworth, Barry. "How do the Mini Vibration Speakers Actually Work?" HOTS Blog. Dec. 17, 2010. (April 11, 2012)

http://www.hotsblog.com.au/how-do-the-mini-vibration-speakers-actually-work.html

j) U.S. Patent & Trademark Office Patent #6,487,300

http://patft.uspto.gov/netacgi/nph-Parser?Sect2=PTO1&Sect2=HITOFF&p=1&u=/netahtml/PTO/search-bool.html&r=1&f=G&l=50&d=PALL&RefSrch=yes&Query=PN/6487300

k) U.S. Patent & Trademark Office Patent application #20060126886

http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=/netahtml/PTO/srchnum.html&r=1&f=G&l=50&s1=20060126886.PGNR.

l) U.S. Patent & Trademark Office Patent application #20060262954

http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=/netahtml/PTO/srchnum.html&r=1&f=G&l=50&s1=20060262954.PGNR.