Patent Description:
Ceiling speakers are used in suspended ceilings, typically for public address, alarm, or musical entertainment purposes. Conventional ceiling speakers are designed for predetermined thicknesses of ceiling tile. Conventional ceiling speakers have fixed acoustic port sizes. Conventional ceiling speakers also load the ceiling tile which can cause deformation or failure of the tile over time. <CIT> discloses reflecting sound waves off one or more adjustably positioned curved surfaces to achieve sound amplification. <CIT> discloses reflecting sound waves off one or more adjustably positioned curved surfaces to achieve sound amplification.

The present invention relates to a small ceiling speaker system as defined in claim <NUM>.

The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and.

The scope of the subject-matter for which protection is sought is defined by the appended claims.

As used and defined herein, "top", "bottom", "upper", "lower", "upward", and "downward" are referenced to the present invention in its installed orientation, as illustrated in <FIG>. As used and defined herein, "speaker" means "loudspeaker" or "tweeter", as shown in <FIG>. As used and defined herein, "diffuser", without more, means an acoustic diffuser for diffusing sound.

<FIG> is a side-bottom perspective view illustrating an exemplary embodiment of the small ceiling speaker system <NUM>, according to a preferred embodiment of the present invention. Small ceiling speaker system <NUM> includes a speaker <NUM>, an acoustic channel <NUM>, and a diffuser <NUM> that is adjustable in two ways. Speaker <NUM> incudes magnet <NUM>, basket <NUM> supporting magnet <NUM>, basket rim <NUM>, support fittings <NUM> (one of four labeled) and surround accommodator <NUM>, which will be discussed in more detail below. Speaker <NUM> directs sound downward when in an installed orientation. Acoustic channel <NUM> includes acoustic channel cone <NUM> and acoustic channel shell <NUM> (see <FIG>) and will be discussed in more detail below. Acoustic channel cone <NUM> is a truncated conical shell extending from the speaker <NUM>. Acoustic channel shell <NUM> (see <FIG>) is a cylindrical shell that is of one piece with acoustic channel cone <NUM>. Adjustable diffuser <NUM> includes diffuser barrel <NUM>, flange <NUM>, diffuser rim <NUM>, and cover plate <NUM> and will be discussed in more detail below. When installed in a ceiling, exterior portions of the small ceiling speaker system <NUM> between flange <NUM> and cover plate <NUM> are visible below a ceiling tile <NUM> (see <FIG>), while the remainder of the small ceiling speaker system <NUM> is not.

<FIG> is a bottom perspective view illustrating an exemplary embodiment of a diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG>, according to a preferred embodiment of the present invention. Flange <NUM> has an inner radially downward sloping portion <NUM> from which three diffuser element supports <NUM> (two visible in this view) extend radially inwardly. The interior surface <NUM> of diffuser barrel <NUM> has partial diffuser threads <NUM> for adjusting the distance between the flange <NUM> and the bottom of the acoustic channel cone <NUM>, to adapt to different thicknesses of ceiling tile <NUM>, <NUM> (see <FIG>). Cover plate <NUM> fits inside diffuser rim <NUM>.

<FIG> is a top perspective view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG>, according to a preferred embodiment of the present invention. Diffuser <NUM> includes diffuser barrel <NUM>, with flange <NUM>, diffuser element supports <NUM>, hub <NUM>, and diffuser element <NUM> with radially symmetric outwardly descending diffuser upper surface <NUM>, demarcations <NUM>, and special demarcation <NUM>. Sets of diffuser threads <NUM> and <NUM> are on opposite sides of the interior surface <NUM> of diffuser barrel <NUM> and each extends no more than ninety degrees around of the interior surface <NUM> of diffuser barrel <NUM>. Diffuser threads <NUM> and <NUM> enable adjustment over a range of ceiling tile <NUM>, <NUM> (see <FIG>) thicknesses. The three diffuser element supports <NUM> are preferably of one piece with hub <NUM>. A screw end <NUM> of fastener <NUM> (see <FIG>) can be seen in threaded bore <NUM> of hub <NUM>. Hub <NUM> has internal threads complimentary to the threads on fastener <NUM>. Inner portions of the three diffuser element supports <NUM> are not affixed to radially symmetric outwardly descending diffuser upper surface <NUM>. Demarcations <NUM> (one labeled of multiple on radially symmetric outwardly descending diffuser upper surface <NUM> give a visual indication, for the installer or operator, of the size of the diffuser acoustic port <NUM> (see <FIG>) ranging upward to diffuser acoustic port <NUM> (see <FIG>). Special demarcation <NUM> is a semi-circumferential groove on radially symmetric outwardly descending diffuser upper surface <NUM> to indicate the optimal adjustment level for this small ceiling speaker system <NUM>. In various other embodiments, other means of making special demarcation <NUM>, such as printing, embossing, painting, or laminating may be used. Grooves <NUM> (one of three labeled) receive the diffuser element supports <NUM> to varying extents, depending on the adjusted size of the diffuser acoustic port <NUM> (see <FIG>) or <NUM> (see <FIG>). The advantage is that many small ceiling speaker systems <NUM> in one large room can be adjusted to be all the same or be adjusted adaptively to an acoustical design using fastener <NUM> (see <FIG>) and the demarcations <NUM>. The diffuser acoustic port <NUM> (see <FIG>) or <NUM> (see <FIG>) are acoustical ports. The small ceiling speaker system <NUM> has a first adjustment over a range of thicknesses of the ceiling tiles (such as <NUM> in <FIG>) and a second adjustment over a range of sizes of the diffuser acoustic port (such as <NUM> in <FIG>).

<FIG> is a bottom perspective view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> in a contracted position, according to a preferred embodiment of the present invention. Diffuser barrel <NUM> protrudes through opening <NUM> in carrier <NUM> in base <NUM> of speaker enclosure <NUM>.

The distance between flange <NUM> and the bottom surface <NUM> of base <NUM> is at a minimum for the illustrated embodiment, representing an adaptation to a relatively thin ceiling tile <NUM> (see <FIG>). Base <NUM> and enclosure <NUM> form small ceiling speaker system <NUM>. Braces <NUM>, <NUM>, <NUM>, and <NUM> are supported on extendable rails <NUM>, <NUM>, <NUM>, and <NUM>, respectively, and are configured to rest on ceiling grid members of a suspended ceiling. The advantage is that the weight of the small ceiling speaker system <NUM> and the enclosure <NUM> does not rest on the tile itself, but are supported entirely on the grid. Extendable rails <NUM>, <NUM>, <NUM>, and <NUM> are shown at variable extents to illustrate extendibility. In practice, the rails <NUM>, <NUM>, <NUM>, and <NUM> on each side are usually extended to equal lengths. Extendable rails <NUM>, <NUM>, <NUM>, and <NUM> are frictionally maintained at length with the help of a steel reed spring <NUM> in each respective track <NUM>, <NUM>, <NUM>, and <NUM> (see <FIG>) in which slides each rail <NUM>, <NUM>, <NUM>, and <NUM>, respectively. In various embodiments, reed spring <NUM> may be made of other materials of equivalent strength and resiliency, such as alloys, plastics, and composites. Bottom panel <NUM> of base <NUM> has a bottom surface <NUM> and a central bottom panel opening <NUM> (see <FIG>), which will be discussed further below.

<FIG> is a bottom perspective view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> in an extended position, according to a preferred embodiment of the present invention. Acoustic channel shell <NUM> extends from acoustic channel cone <NUM>. Shell threads <NUM> extend no more than ninety degrees around acoustic channel shell <NUM> and include a second set of similar threads one hundred and eighty degrees from the shell threads <NUM> shown. Unthreaded portions of the shell surface <NUM> space apart first and second sets of shell threads <NUM>. The diffuser threads <NUM>, <NUM> within the diffuser <NUM> may engage or disengage shell threads <NUM> on acoustic channel shell <NUM>, depending on the angle of rotation of diffuser <NUM>. When diffuser threads <NUM>, <NUM> align to unthreaded portions of the shell surface <NUM> between shell threads <NUM>, the threads disengage. Height adjustment of the diffuser <NUM> is done by rotating the flange <NUM> to disengage diffuser threads <NUM>, <NUM> from shell threads <NUM>, sliding the diffuser <NUM> up and down to position the flange <NUM> flush with the bottom surface <NUM> of ceiling tile <NUM> (see <FIG>), then rotating the diffuser <NUM> to re-engage the diffuser threads <NUM>, <NUM> with shell threads <NUM>. The distance between flange <NUM> and the bottom surface <NUM> of base <NUM> is at a maximum for the illustrated embodiment, representing an adaptation to a relatively thick ceiling tile <NUM> (see <FIG>).

<FIG> is a side elevation view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> with the diffuser <NUM> in an extended position, according to a preferred embodiment of the present invention. While the diffuser <NUM> is adjusted for a thick ceiling tile <NUM> (see <FIG>), the diffuser acoustic port <NUM> (see <FIG>) is at an intermediate size, as shown by the relationship of diffuser element support <NUM> with the bottom of groove <NUM> in diffuser element <NUM>. The isolation of shell threads <NUM> between unthreaded portions of the shell surface <NUM> can be clearly seen.

<FIG> is a bottom plan view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, according to a preferred embodiment of the present invention. Cover plate <NUM> is preferably a material that is attracted to magnets. In some embodiments cover plate <NUM> may be adhered by non-magnetic means, be translucent, and/or have one or more light sources behind it for signaling, such as for alarms, alerts, etc. Cover plate <NUM> may bear a logo or design, or be colored and designed to blend in with the texture and color of a ceiling tile. Support fitting <NUM> (one of four labeled) have respective fastener bores <NUM> (one of four labeled).

<FIG> is a side-top exploded perspective view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, according to a preferred embodiment of the present invention. The full length of acoustic channel shell <NUM> is shown, which is preferably the same length as the diffuser barrel <NUM>. Diffuser acoustic port <NUM> (see <FIG>) is near a minimum.

<FIG> is a side-top perspective view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG> with the diffuser <NUM> in a contracted position, according to a preferred embodiment of the present invention. Diffuser <NUM> is adjusted for a minimum thickness ceiling tile <NUM> (see <FIG>). Diffuser acoustic port <NUM> (see <FIG>) is near a minimum.

<FIG> is a cross sectional elevation view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG> and <FIG> in a contracted position, according to a preferred embodiment of the present invention. Small ceiling speaker system <NUM> is shown supported on base <NUM> and covered by enclosure <NUM>. A ceiling tile <NUM> of small thickness for the illustrated embodiment is shown positioned with its bottom surface <NUM> flush to a top surface of flange <NUM> and its top surface <NUM> abutting base <NUM>. The tweeter <NUM> and details of the speaker <NUM> are shown. Diaphragm <NUM> is driven by coil <NUM>. Diaphragm <NUM> attaches to basket rim <NUM> via surround <NUM>. The deformation of surround <NUM> is accommodated by surround accommodator <NUM>. Channeling audio down through a smaller tube creates acoustic reflections adversely effecting sound quality. The acoustic channel <NUM> solves this problem by reducing internal reflections and allowing for a cleaner pressure wave to exit the small ceiling speaker system <NUM>. Tweeter <NUM> is oriented to project sound directly onto the radially symmetric outwardly descending diffuser upper surface <NUM> of diffuser <NUM>. Diffuser element <NUM> includes the radially symmetric outwardly descending diffuser upper surface <NUM>, the diffuser rim <NUM>, the demarcations <NUM>, the special demarcation <NUM>, and the body on which such features are mounted. Electrical connectors <NUM> on enclosure <NUM> provide audio signal connectivity through the enclosure <NUM>.

<FIG> is a cross sectional elevation view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG> and <FIG> in an extended position, according to a preferred embodiment of the present invention. A ceiling tile <NUM> of greater thickness for the illustrated embodiment is shown positioned with its bottom surface <NUM> flush to a top surface of flange <NUM> and its top surface <NUM> abutting base <NUM>.

<FIG> is a bottom plan view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, according to a preferred embodiment of the present invention. The extension of inner radially downward sloping portion <NUM> beyond diffuser rim <NUM> as a support for diffuser element supports <NUM> can be seen. The diameter of flange <NUM> is preferably no larger than a fire suppression sprinkler head flange, enabling the small ceiling speaker system <NUM> to be unobtrusive. Cover plate <NUM> is seated within diffuser rim <NUM>.

<FIG> is a side view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, according to a preferred embodiment of the present invention. Demarcations <NUM> provide a user with a visual indication of the extent that the diffuser element <NUM> has been adjusted away from flange <NUM>. Groove <NUM> (one labeled of one visible of three) alongside of demarcations <NUM> receives diffuser element support <NUM> at all times and thereby prevents diffuser element <NUM> from rotating when fastener <NUM> is rotated. The diffuser element <NUM> is shown at an intermediate distance from flange <NUM>. Notch <NUM> in diffuser rim <NUM> assists with removal of the cover plate <NUM>.

<FIG> is a top plan view illustrating an exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, according to a preferred embodiment of the present invention. Twelve demarcations <NUM> (one labeled) are shown in this view. The number of demarcations <NUM> is not a limitation of the present invention. Demarcations <NUM> are preferably printed onto radially symmetric outwardly descending diffuser upper surface <NUM>. In other embodiments, demarcations <NUM> may be embossed, engraved, printed, laminated, or molded into the original radially symmetric outwardly descending diffuser upper surface <NUM>.

<FIG> is an exploded bottom-side perspective view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, according to a preferred embodiment of the present invention. Diffuser element <NUM> includes a cover plate support surface <NUM>, three magnet cups <NUM> and a spring-receiving cavity <NUM> for containing coil spring <NUM>. Fastener <NUM>, illustrated as an Allen-head screw, is to be inserted into the spring-receiving cavity <NUM> and within the coil of coil spring <NUM> and threaded into threaded bore <NUM> of hub <NUM>. Magnets <NUM> (one labeled of three) are secured in magnet cups <NUM> (one labeled of three) and are used to hold cover plate <NUM> in place within diffuser rim <NUM>. Once installed, rotating fastener <NUM> adjusts the distance between diffuser element <NUM> and flange <NUM> and, consequently, the size of diffuser acoustic port <NUM> (see <FIG>). The extent of the range of bidirectional adjustability of the diffuser acoustic port <NUM> is predetermined by the threaded length of fastener <NUM> and the threaded length of threaded bore <NUM> in hub <NUM>.

<FIG> is an exploded top-side perspective view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, according to a preferred embodiment of the present invention. An unthreaded portion <NUM> of the interior surface <NUM> of diffuser barrel <NUM> can be seen bracketing diffuser threads <NUM> and <NUM>. Spring-receiving opening <NUM> in diffuser element <NUM> can be seen in this view. Two of the grooves <NUM> can be seen in this view.

<FIG> is a top plan view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, and defining cross section AA, according to a preferred embodiment of the present invention. A collar <NUM> on diffuser element <NUM> that surrounds spring-receiving opening <NUM> into diffuser element <NUM> is noticeable in this view.

<FIG> is a side cross sectional view through cross section AA illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, according to a preferred embodiment of the present invention. Coil spring <NUM> is shown compressed within spring receiving cavity <NUM> and capped by hub <NUM>. Fastener <NUM> extends through the coil of coil spring <NUM> and threads into hub <NUM>. Fastener <NUM> is preferably captive once the small ceiling speaker system <NUM> is assembled. Magnet <NUM> is secured in magnet cup <NUM> by adhesive, friction, screw threads, snap fit, or similarly effective means. A cross section of groove <NUM> is visible in this view, and shows that the groove <NUM> is deepest nearer the center of diffuser element support <NUM>. In various embodiments, the flat bottom surface <NUM> of the groove <NUM> and the flat bottom surface <NUM> of the diffuser element support <NUM> may be other than flat, within the constraint that they are conformal. In other various embodiments that the shapes need not be conformal.

<FIG> is a side elevation view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> and <FIG>, with the diffuser acoustic port <NUM> reduced, according to a preferred embodiment of the present invention. Diffuser acoustic port <NUM> is shown almost at a reduced size, as shown by the small distance between diffuser element supports <NUM> and the flat bottom surface <NUM> of groove <NUM> in diffuser element <NUM>.

<FIG> is a side elevation view illustrating the exemplary embodiment of the diffuser <NUM> of the small ceiling speaker system <NUM> of <FIG> with the diffuser acoustic port <NUM> enlarged, according to a preferred embodiment of the present invention. Diffuser acoustic port <NUM> is shown at nearly a maximum size, as shown by separation between diffuser element supports <NUM> and diffuser element <NUM>.

<FIG> is a front side upside down elevation view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG> and <FIG> with enclosure <NUM> and braces <NUM>, <NUM>, <NUM>, and <NUM>, according to a preferred embodiment of the present invention. The front side is arbitrarily designated as the side opposite the side having electrical connectors <NUM>.

<FIG> is a top plan view illustrating the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG> and <FIG> with enclosure <NUM> and braces <NUM>, <NUM>, <NUM>, and <NUM>, according to a preferred embodiment of the present invention. Access panel <NUM> is releasably fastened to enclosure <NUM>. Enclosure <NUM> includes perimeter flange <NUM>, which fits within rim <NUM> of base <NUM>. Perimeter flange <NUM>, and thus enclosure <NUM>, is held to base <NUM> with fasteners <NUM> (one of sixteen labeled). Decorative vent <NUM> assists in releasing hot air from within enclosure <NUM>, as do elongated vents <NUM> (one of two labeled).

<FIG> is a rotated left side elevation view illustrating an exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, and <FIG> with enclosure <NUM> and braces <NUM> and <NUM>, according to a preferred embodiment of the present invention. While the illustrated enclosure <NUM> and base <NUM> are preferred, those of skill in the art, illuminated by the present disclosure, will understand that a wide variety of enclosures of various shapes and sizes may support ceiling speaker <NUM>, acoustic channel <NUM>, and diffuser <NUM> within the scope of the present invention as defined by the appended claims.

<FIG> is a rotated right-side elevation view illustrating an exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG> and <FIG> with enclosure <NUM> and braces <NUM> and <NUM>, according to a preferred embodiment of the present invention. Enclosure <NUM> is preferably made of metal. Base <NUM> is preferably made of injection molded plastic. In various other embodiments, other materials may be used that meet similar strength, durability, and fire code requirements as the preferred materials.

<FIG> is a bottom plan view illustrating an exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, and <FIG> with enclosure <NUM> and braces <NUM>, <NUM>, <NUM>, and <NUM>, according to a preferred embodiment of the present invention. The illustrated portion of carrier <NUM> is the bottom surface of carrier <NUM>, which preferably sits flush with the bottom surface <NUM> of base <NUM>, supports the small speaker system <NUM>, and releasably fastens to base <NUM>. The advantage of this approach is that the speaker <NUM> and tweeter <NUM> can be accessed without otherwise opening the enclosure <NUM>. The bottom of carrier <NUM> is an annular piece with an optional delineated outer ring <NUM> having fastener openings <NUM> (one of four labeled) for fasteners <NUM> (one of four labeled), illustrated here as screws <NUM>. In various embodiments, the outer ring <NUM> may not be delineated and there may be more or fewer fastener openings <NUM>.

<FIG> is a rear side elevation view illustrating an exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, and <FIG> with enclosure <NUM> and braces <NUM>, <NUM>, and <NUM>, according to a preferred embodiment of the present invention. Access panel <NUM> is releasably secured by fasteners <NUM> (one of three labeled). Strain relief loop <NUM> reduces strain on electrical wires attached to electrical connectors <NUM>.

<FIG> is a low-angle rear exploded view illustrating an exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, and <FIG>, according to a preferred embodiment of the present invention. Electrical connectors <NUM> are seen to be on a threaded plug to be installed in opening <NUM> that uses a lower opening on strain relief loop <NUM> as a washer and is secured with a nut (not shown). Perimeter flange <NUM> of enclosure <NUM> has predrilled fastener holes <NUM> (one of ten visible labeled) for fastening to base <NUM>, which has corresponding fastener holes (not shown) for fasteners <NUM> (one of nine visible labeled). Reed spring <NUM> (one of two visible of four labeled) is attachable to extend through spring window <NUM> in track <NUM> to visible of four labeled) is attachable to extend through spring window <NUM> in track <NUM> to provide friction for extendable rail <NUM>, when mounted. Tracks <NUM> and <NUM> are similarly equipped for rails <NUM> and <NUM>, respectively. Rail <NUM> has a similarly equipped guide (not visible in this view). Central base opening <NUM> in base <NUM> has four inwardly extending tabs <NUM> (one of two visible of four labeled) for receiving fasteners <NUM> (one of four labeled) to fasten the carrier <NUM> to the base <NUM>. Central bottom panel opening <NUM> in bottom panel <NUM> aligns with central base opening <NUM> in base <NUM>. Base fasteners <NUM> (one of two visible labeled) fasten to fastener fittings <NUM> extending from a top surface of bottom panel <NUM> via fastener holes <NUM> (one of three visible labeled).

<FIG> is a high-angle rear exploded view illustrating an exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, and <FIG>, according to a preferred embodiment of the present invention. Electronics, including a multi-tapped transformer <NUM> can be seen mounted on base <NUM>. In various embodiments, respectively various electronics packages, such as amplifiers, filters, controls, etc., may be mounted on base <NUM>. Fastener fittings <NUM> (one of seven visible of eight labeled) may be better seen in this view. Carrier fastener receivers <NUM> extend upwards from annular plate <NUM> (see <FIG>) to align with support fittings <NUM> and then fasteners <NUM> extend through speaker basket rim <NUM>, support fittings <NUM>, and into carrier fastener receivers <NUM> to fasten the small ceiling speaker system <NUM> to the carrier <NUM>.

<FIG> is a top perspective view illustrating an exemplary mounted base of the exemplary embodiment of the small ceiling speaker system of <FIG>, <FIG>, <FIG>, and <FIG> and delineating detail A, according to a preferred embodiment of the present invention. The carrier <NUM> is fastened to completing the mounting of small ceiling speaker system <NUM> to the base <NUM>.

<FIG> is a top perspective view illustrating an exemplary detail A of the mounted base <NUM> of the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, <FIG> and <FIG>, according to a preferred embodiment of the present invention. Reed spring <NUM> is secured with fastener <NUM> to extend through spring window <NUM> in track <NUM> to frictionally engage a surface <NUM> of rail <NUM>. Each track <NUM>, <NUM>, <NUM>, and <NUM> is similarly arranged to frictionally engage its respective rail <NUM>, <NUM>, <NUM>, and <NUM>.

<FIG> is a top perspective view illustrating an exemplary embodiment of a carrier <NUM> of the exemplary embodiment of the small ceiling speaker system of <FIG>, <FIG>, and <FIG>, according to a preferred embodiment of the present invention. Carrier <NUM> is a physical interface between the speaker <NUM> and the base <NUM>. Carrier <NUM> includes an annular plate <NUM> having an outer perimeter <NUM>, a top surface <NUM>, and an inner opening <NUM> with a perimeter <NUM>. Inner opening <NUM> is sized to receive acoustic channel shell <NUM>. Extending upward from the top surface <NUM> are four alignment pins <NUM> (one of four labeled) that fit, as a group, slidingly within central openings <NUM> and <NUM>. Also extending upward from the top surface <NUM> are four carrier fastener receivers <NUM> with threaded bores <NUM> (one of four of each labeled). Carrier fastener receivers <NUM> align to support fittings <NUM> to receive fasteners <NUM>, such as bolts <NUM>, to fasten the carrier <NUM> to the speaker <NUM>. Fastener openings <NUM> align with tabs <NUM> to receive fasteners <NUM> to fasten the carrier <NUM> to the base <NUM>. In various embodiments using speakers <NUM> having respective various patterns of support fittings <NUM>, the arrangement of carrier fastener receivers <NUM> may be complimentary to the support fittings <NUM>. The advantage of carrier <NUM> is that it enables removal of the speaker <NUM> for maintenance or replacement without otherwise opening enclosure <NUM>.

<FIG> is a bottom perspective view illustrating an exemplary embodiment of a carrier <NUM> of the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, <FIG>, and <FIG>, according to a preferred embodiment of the present invention. The outer rim <NUM> is preferably flush with bottom surface <NUM> of annular plate <NUM>. The inner rim <NUM> is preferably flush with bottom surface <NUM> of annular plate <NUM>. In some embodiments, the delineation of outer rim <NUM> and/or inner rim <NUM> may be omitted. The indentations <NUM> (one of sixteen labeled) have no function beyond aesthetics.

<FIG> is a bottom plan view illustrating the exemplary embodiment of the carrier <NUM> of the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, <FIG>, and <FIG>, according to a preferred embodiment of the present invention. Alignment pins <NUM> are arranged at corners of an imaginary square, which just fits into central openings <NUM> and <NUM>. In some embodiments, other patterns having the same functionality may be used. Fastener openings <NUM> may be countersunk, such that no portion of a fastener extends below the bottom surface <NUM>. In some embodiments, outer rim <NUM> may be thicker than annular plate <NUM>.

<FIG> is a front elevation view illustrating the exemplary embodiment of the carrier <NUM> of the exemplary embodiment of the small ceiling speaker system <NUM> of <FIG>, <FIG>, <FIG>, and <FIG>, according to a preferred embodiment of the present invention. Alignment pins <NUM> are taller than carrier fastener receivers <NUM> in order to engage the inner edges of central openings <NUM> and <NUM>. The two vertical lines on the labeled carrier fastener receivers <NUM> delineate the flat portion of the side of carrier fastener receivers <NUM>.

Claim 1:
A small ceiling speaker system (<NUM>) comprising an acoustic diffuser (<NUM>) wherein
said acoustic diffuser (<NUM>) comprises:
i. a diffuser barrel (<NUM>) comprising a cylindrical shell;
ii. two opposed circumferentially-spaced apart sets of internal diffuser threads (<NUM> and <NUM>), each set extending no more than ninety degrees around an internal surface (<NUM>) of said diffuser barrel (<NUM>);
iii. a circumferential flange (<NUM>) extending radially inward and outward from a lower end of said diffuser barrel (<NUM>);
iv. a plurality of diffuser element supports (<NUM>) extending radially inward from a radially inward extending portion (<NUM>) of said circumferential flange (<NUM>); and converging on, and of one piece with, an axially central hub (<NUM>); and
v. a threaded bore (<NUM>) in said hub (<NUM>);
vi. a diffuser element (<NUM>), said diffuser element (<NUM>) comprising:
(a) a body having a circular circumference;
(b) an upper radially symmetric outwardly descending diffuser surface (<NUM>) on said body;
(c) a plurality of demarcations (<NUM>) on said upper radially symmetric outwardly descending diffuser surface (<NUM>);
(d) a plurality of radial grooves (<NUM>) in said upper radially symmetric outwardly descending diffuser surface (<NUM>), each positioned to receive one diffuser element support (<NUM>) of said plurality of diffuser element supports (<NUM>);
(e) a flat lower surface on said body;
(f) a circumferential rim (<NUM>) on said lower surface of said body;
(g) a central bore through said body in three diameters configured to receive a coiled spring (<NUM>), a fastener (<NUM>) extending through said coiled spring (<NUM>), and a fastener head; wherein said fastener (<NUM>) comprises a threaded portion sized to extend through and beyond said central bore and threaded into said threaded bore (<NUM>) of said hub (<NUM>);
wherein rotation of said fastener (<NUM>) adjusts a distance between said diffuser element (<NUM>) and the flange (<NUM>) and thereby the size of an acoustic port (<NUM>) of said diffuser (<NUM>).