The present invention relates generally to speaker systems for use with computer systems and, more particularly, to a woofer/subwoofer speaker apparatus contained within a computer housing. More particularly still, the present invention relates to a speaker assembly that, during manufacture, is quickly and easily placed within a computer housing, that occupies a limited volume and that is universally designed so as to be adaptable in various orientations.
Audio speaker systems are well known in the art. Speaker systems have evolved from a single monaural speaker to multiple speakers that produce stereo sound that is more realistic sounding to the typical listener. Each speaker unit in a stereo speaker system typically comprises a plurality of speaker drivers within a single enclosure. The speaker unit typically uses two to three speakers, or more, with one speaker reproducing upper frequencies and another speaker reproducing lower frequencies. A third speaker sometimes is added to reproduce the lowest frequencies desired.
Recently, however, the trend has been to utilize multiple channels, which has led to using separate enclosures for each speaker. This allows the speaker system to have smaller components with the ability to place the speakers in discrete locations otherwise not possible with the larger enclosures typically used in previous speaker designs. Additionally, the woofer/subwoofer unit in the satellite speaker systems typically only produces a monaural tone as well and thus a second, matching stereo speaker is not necessary. With this in mind, speaker designers have attempted to optimize the acoustics reproduction of small, enclosed subwoofer designs in order to save on space or to locate this speaker unit in less conspicuous locations.
Another advance in subwoofer speaker design that has decreased the overall unit size is the utilization of ported chambers. The ported chambers also enhance the sound quality of the speaker system, as well as increase the speaker's responsiveness without adding to, or in some instances by even minimizing, the inherent distortion of the speaker. One design for a ported speaker system is shown in U.S. Pat. No. 5,623,132 issued Apr. 22, 1997, entitled “Module Port Tuning Kit.” This reference discloses the concept of adding a modular port to a speaker enclosure to enhance the responsiveness and accuracy of the speaker itself. A more complicated enclosure system is disclosed in U.S. Pat. No. 5,147,986, issued Sep. 15, 1992, entitled “Subwoofer Speaker System.” This patent discloses a subwoofer system that divides the enclosure into at least three chambers. Each chamber is tuned and acoustically coupled, one to another, so as to optimize speaker responsiveness while minimizing the enclosure volume. Both of these patents disclose what would be excellent speaker designs for designing and implementing a subwoofer speaker assembly that stands alone.
The use of speaker systems has expanded from that of reproducing sound in a stereo system to reproducing a rich, sonorous environment of surround sound in multi-media systems that include video replay in television and personal computer systems. It is in the computer multi-media system that conventional speaker systems such as those disclosed in the above-referenced patents, although useful, have several drawbacks. For one, both such speaker systems still require a separate enclosure that occupies a certain amount of space. In a multi-media computer system, one must include not only the CPU box of the computer system, but also the monitor, keyboard, pointing device, printer, and any auxiliary peripheral devices that take up valuable desk or floor real estate either at home or in the office. Adding multi-media capabilities to the computer system requires sound to be reproduced and, to reproduce stereo sound, at least two speakers are required for a right and left channel. Early personal computer systems included a monaural single speaker that was mounted within the computer system and only provided amusing beeps and tones, but never could duplicate stereo sound or full, rich audio sound currently desired by today's users.
Accordingly, the same type of satellite speaker systems that have been used in both audio high-fidelity systems and video systems with audio high-fidelity have made their way to the market of personal computers. These include a right channel speaker, a left channel speaker, and a monaural subwoofer unit. This requires three new components to be placed on the already crowded desktop of the computer user. Some users have freed up desk space by placing the CPU box on the floor or in another, out-of-the-way location. Such an approach is helpful in that additional desktop space is then available. Further, the user can place the subwoofer anywhere close, without it having to be optimally positioned as is required by the right or left speaker. This is because the subwoofer does not produce stereophonic sound, but merely enhances the audio experience by providing the lower frequencies. It is well known to speaker design engineers that a single subwoofer system is more than adequate for reproducing the low frequency end of the audio spectrum needed for full audio reproduction.
Placing the CPU box under the desk or moving it away from the desktop, as well as moving the subwoofer system off the desktop and in an inconspicuous place, are good approaches to provide additional desktop real estate. Unfortunately, they create additional clutter either under the desk or in the separate storage area where the two units must be provided. Additionally, in shipping systems with multiple speaker sets, a larger shipping box is necessary to accommodate the typically much-larger subwoofer assembly than the two satellite speakers. This, in turn, incurs additional shipping costs as well as packing costs in terms of material and labor and time delays experienced in packing the unit.
Thus, what is needed is a satellite speaker system that overcomes the storage problems of the prior art by placing a subwoofer somewhere useful to the end user, and without taking up unnecessary space otherwise required by the user. This advantage would also reduce the costs of packing, shipping, and handling of an entire multi-media computer system. Further, such a subwoofer configuration should have the same acoustic benefits that ported subwoofer designs offer.
According to the present invention, an internal subwoofer apparatus is provided that is placed within the central processing unit (CPU) box of a computer system. The computer system may be a multi-media personal computer system that is capable of providing visual and audio recording and playback. The CPU box typically includes the motherboard that houses the main central processing unit as well as any ancillary processing chips needed for the computer system. The CPU box may also include memory modules such as short-term random access memory, long-term disk storage memory in the form of hard disk drives or removable floppy disk drive systems, as well as long-term hard disk storage units such as CD-ROM systems. User input to the computer system may be provided by a keyboard and, optionally, a pointing device, such as a mouse or track ball. A monitor that displays video signals viewable by the user may be provided and connected to the CPU and driven by either the main central processing unit or a separate video processor, such as a video card. An audio system may be provided that includes a pair of satellite speakers serving as a first channel and a second channel, typically known as the right and left channels, and further includes a subwoofer unit located in the CPU box. The CPU box can be oriented in a tower configuration or a desktop configuration.
The subwoofer unit is mounted in a lower front portion of the box, if it is a tower box, or in a front side portion, if it is a desktop box. The subwoofer is ported to enhance audio reproduction and to conserve space. The speaker may be mounted in a down-fire position, meaning that the front of the speaker is mounted downwardly against a vibration and sound-absorbing mat, while the reflecting sound echoes within the chamber and then is enhanced through the port that opens to the front of the computer system. A separate volume control and on/off switch can be provided on the exterior of the CPU so as to either activate or deactivate the subwoofer within the CPU box. The switch and the subwoofer are coupled to the motherboard or, alternatively, to an audio sound card installed within a computer system.
As depicted in
Further included in CPU box 12 is subwoofer controller 32. Subwoofer controller 32 is coupled to both subwoofer 22 and to CPU 30. Subwoofer controller 32 may also be coupled to an audio sound card 28. Subwoofer controller 32 activates subwoofer 22 when the computer system 10 is on, thus supplying power to subwoofer 22. Additionally, subwoofer controller 32 includes a volume control device that allows the user to adjust the volume to a desired level. Subwoofer apparatus 22 further includes a speaker 34. Speaker 34 is mounted against the bottom surface of the container used for subwoofer 22. Speaker 34 may range in diameter from three inches to as large as six inches, or more, depending on the size of the CPU box 12. The dimensions of subwoofer 22 are dictated by the size of CPU box 12. For a large box, subwoofer 22 can occupy a relatively larger volume. For a smaller box, subwoofer 22 would be sized accordingly.
In one embodiment, the interior dimensions of subwoofer 22 are five inches on all sides to form a five-inch cube. The diameter of speaker 34 thus can be no greater than five inches. In this embodiment, it is desired that the speaker diameter be four inches.
To enhance the audio response of subwoofer apparatus 22 and keep its size compact, a port 36 is provided. Port 36 is adjusted so that it has a length of substantially four-fifths the depth of the container for subwoofer 22 and a diameter of substantially one-fifth of the height of the container. Further, the port is placed at substantially one-fifth of the height of the top container portion and is centered across the front portion of the container. Thus, for a five-inch cube container structure, port 36 will be four inches long with a diameter of substantially one inch and off-set substantially one inch from the top of the container for subwoofer 22. Additionally, the front portion of port 36 tapers outward to a diameter larger than the inner diameter of port 36. The second diameter is at a ratio of substantially 1.5:1 to the first diameter. In alternative embodiments, the container for subwoofer apparatus 22 may have a greater height, greater width, or greater depth. These dimensions are determined by the audio response desired by the speaker designer, as well as the space limitations found within the CPU box 12. For example, a container box that is seven inches high, six inches deep, and six inches in width would allow for a larger speaker driver to be placed therein and a sound port having a larger volume because of the larger box dimensions.
Once container units 42 and 44 are mated, a plurality of speaker fasteners 24 is inserted into subwoofer apparatus 22. A fastener 24 is inserted in each corner to secure speaker 34 in place as well as to hold container units 42 and 44 together. Speaker 34 is electrically connected to connector 40 that provides connection to the CPU located in CPU box 12. Speaker 34 is placed on motion and sound dampener 38. Motion and sound dampener 38 is made of a desired dampening material suitable for use in an acoustical speaker assembly. This can include a flexible rubber mat, a neoprene mat, or a fiberglass liner. Motion and sound dampener 38 serves to isolate speaker 34 from the vibrations encountered within CPU box 12 as well as to dampen any acoustic vibration caused by the speaker within the box and lessen interference in the performance of subwoofer 22. Additional acoustic dampening material may be lined within subwoofer 22 as desired.
As will be apparent to those skilled in the art, a number of variations and modifications of the described invention can also be used. Port shapes other than the round port thus depicted can be used, such as oval, elliptical, parabolic, square, rectangular, and other polygonal shapes. A single port can be replaced by two or more smaller ports. The subwoofer assembly can employ more than one speaker as well as more than one chamber. The absolute and relative sizes of the chambers, or enclosures, can be adjusted, particularly as needed to adjust the frequency response in coordination with the characteristics of other speakers, such as the midrange or tweeter speakers that are found in the satellite pair of speakers 20. Although standard conical speakers are depicted, other shapes of speakers can be used, such as parabolic, oval, elliptical, planar, and the like.
When speaker apparatus 22 is used as a subwoofer speaker, a low frequency bi-pass circuit is provided that cuts off signals having a frequency greater than about 100-120 hertz. A typical bypass filter is a resister-capacitor circuit that is tuned to allow signal frequencies of 100-120 hertz or lower to pass to speaker 34. If speaker 34 is to also reproduce higher frequencies, then a higher bypass filter would be required. Typically, in such an instance, the cut-off level would be at 200 hertz and above. Thus, the RC circuit would be tuned to pass frequencies at 200 hertz or below for output on speaker 34. It is, of course, understood that the cut off should not be taken as limited to 100 or 200 hertz, but may extend to a higher frequency as desired.
Although the invention has been described by way of a preferred embodiment and various modifications and variations, other modifications and variations can also be used within the scope of the invention, the invention being defined by the appended claims and equivalence thereof.
This application is a divisional of application Ser. No. 10/226,870, filed Aug. 23, 2002, pending, which is a divisional of application Ser. No. 09/098,779 filed Jun. 17, 1998, now U.S. Pat. No. 6,546,298, issued Apr. 8, 2003.
Number | Date | Country | |
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Parent | 10226870 | Aug 2002 | US |
Child | 11486612 | Jul 2006 | US |
Parent | 09098779 | Jun 1998 | US |
Child | 10226870 | Aug 2002 | US |