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83-664: Sound Blaster Advanced Wave Effects 64 is an ISA sound card from Creative Technology . It is an add-on board for PCs . The card was launched in November 1996. The Sound Blaster AWE64 is significantly smaller than its predecessor, the Sound Blaster AWE32 . It offers a similar feature set, but also has a few notable improvements. AWE64 has support for greater polyphony than the AWE32. Unfortunately, these additional voices are achieved via software-based processing on

166-724: A 16-bit transfer size, signal timing in the PIO modes and the interrupt and DMA mechanisms. The PC/XT-bus is an eight- bit ISA bus used by Intel 8086 and Intel 8088 systems in the IBM PC and IBM PC XT in the 1980s. Among its 62 pins were demultiplexed and electrically buffered versions of the 8 data and 20 address lines of the 8088 processor, along with power lines, clocks, read/write strobes, interrupt lines, etc. Power lines included −5 V and ±12 V in order to directly support pMOS and enhancement mode nMOS circuits such as dynamic RAMs among other things. The XT bus architecture uses

249-549: A 5.1-channel 16-bit/48 kHz Dolby Digital format at 640 kbit/s and transports it via a single S/PDIF cable. A similar technology known as DTS Connect is available from competitor DTS . An important benefit of this technology is that it enables the use of digital multichannel sound with consumer sound cards, which are otherwise limited to digital PCM stereo or analog multichannel sound because S/PDIF over RCA, BNC, and TOSLINK can only support two-channel PCM, Dolby Digital multichannel audio, and DTS multichannel audio. HDMI

332-528: A division of Lucasfilm Ltd. , co-developed Dolby Digital Surround EX ™ for the release of Star Wars: Episode I – The Phantom Menace . Dolby Digital Surround EX has since been used on the DVD releases of the Star Wars prequel and original trilogies. Dolby Digital Live (DDL) is a real-time encoding technology for interactive media such as video games. It converts any audio signals on a PC or game console into

415-439: A fall-back option in case of damage to the data area or failure of the digital decoding; it also provides compatibility with projectors not equipped with digital soundheads. Almost all modern cinema prints are of this type and may also include SDDS data and a timecode track to synchronize CD-ROMs carrying DTS soundtracks. The simplest way of converting existing projectors is to add a so-called penthouse digital soundhead above

498-524: A few unique signal lines specific to ATA/IDE hard disks (such as the Cable Select/Spindle Sync. line.) In addition to the physical interface channel, ATA goes beyond and far outside the scope of ISA by also specifying a set of physical device registers to be implemented on every ATA (IDE) drive and a full set of protocols and device commands for controlling fixed disk drives using these registers. The ATA device registers are accessed using

581-570: A full 640 kbit/s. Some Sony PlayStation 2 console games are able to output AC-3 standard audio as well, primarily during pre-rendered cutscenes. Dolby is part of a group of organizations involved in the development of AAC (Advanced Audio Coding), part of MPEG specifications, and considered the successor to MP3. Dolby Digital Plus (DD-Plus) and TrueHD are supported in HD-DVD, as mandatory codecs, and in Blu-ray Disc, as optional codecs. In

664-500: A hardware Dolby Digital decoder. The six extra phono plugs (sub, center, left rear, right rear, digital in, digital pass-through) and the extra Dolby decoder chips were placed on a second board which connected to the main board via a ribbon cable. The project was dropped in favor of the Sound Blaster Live! cards due to the high expense of such a solution, and the aging ISA interface. In response to Creative's move towards

747-717: A proprietary memory module, Jeff Briden created an adapter board that plugged into the AWE64 and allowed the user to install normal 30-pin SIMMs . The AWE-SIMM was available for several years starting in 1998 but is no longer available. In 1998, Beijing Luck Star Power Machines Co, Ltd. had designed an adapter board named SIMMConn that could be plugged into AWE64 and allowed to install a single 72-pin SIMM module. The adapter came in two variants: SIMMConn Value – designed for AWE64 and AWE64 Value, and SIMMConn Gold – designed for AWE64 Gold. Although

830-453: A second 8259 PIC (connected to one of the lines of the first) and 4 × 16-bit DMA channels, as well as control lines to select 8- or 16-bit transfers. The 16-bit AT bus slot originally used two standard edge connector sockets in early IBM PC/AT machines. However, with the popularity of the AT architecture and the 16-bit ISA bus, manufacturers introduced specialized 98-pin connectors that integrated

913-506: A separate SPDIF output). The earlier revision of the standard and value versions of the card (i.e. Model CT4500) had all-black jacks, but a later revision (model CT4520) had color coded jacks. A third version that arrived later, was designed around the PCI bus. It offers the features of the original ISA AWE64, but it has the PCI interface and is built around an even more integrated ASIC . This made

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996-579: A separate clock generator, or a clock divider which either fixed the ISA bus frequency at 4, 6, or 8 MHz or allowed the user to adjust the frequency via the BIOS setup. When used at a higher bus frequency, some ISA cards (certain Hercules-compatible video cards, for instance), could show significant performance improvements. Memory address decoding for the selection of 8 or 16-bit transfer mode

1079-602: A single Intel 8259 PIC , giving eight vectorized and prioritized interrupt lines. It has four DMA channels originally provided by the Intel 8237 . Three of the DMA channels are brought out to the XT bus expansion slots; of these, 2 are normally already allocated to machine functions (diskette drive and hard disk controller): The PC/AT-bus , a 16- bit (or 80286-) version of the PC/XT bus,

1162-603: A time, but this allowed for greater flexibility. The AT Attachment (ATA) hard disk interface is directly descended from the 16-bit ISA of the PC/AT. ATA has its origins in the IBM Personal Computer Fixed Disk and Diskette Adapter, the standard dual-function floppy disk controller and hard disk controller card for the IBM PC AT; the fixed disk controller on this card implemented the register set and

1245-454: Is a derivative of the ISA bus, utilizing the same signal lines with different connectors. The LPC bus has replaced the ISA bus as the connection to the legacy I/O devices on current motherboards; while physically quite different, LPC looks just like ISA to software, so the peculiarities of ISA such as the 16 MiB DMA limit (which corresponds to the full address space of the Intel 80286 CPU used in

1328-414: Is a series of frames; the frame size code is used along with the sample rate code to determine the number of (2-byte) words before the next syncword. Channel blocks can be either long, in which case the entire block is processed as single modified discrete cosine transform , or short, in which case two half length transforms are performed on the block. Below is a simplified AC-3 header. A detailed description

1411-528: Is an advanced lossless audio codec based on Meridian Lossless Packing . Support for the codec was mandatory for HD DVD and is optional for Blu-ray Disc hardware. Dolby TrueHD supports 24-bit bit depths and sample rates up to 192 kHz. Maximum bitrate is 18 Mbit/s while it supports up to 16 audio channels (HD DVD and Blu-ray Disc standards currently limit the maximum number of audio channels to eight). It supports metadata, including dialog normalization and Dynamic Range Control. Although commonly associated with

1494-482: Is equipped with two ISA slots. It was marketed to industrial and military users who had invested in expensive specialized ISA bus adaptors, which were not available in PCI bus versions. Similarly, ADEK Industrial Computers released a modern motherboard in early 2013 for Intel Core i3/i5/i7 processors, which contains one (non-DMA) ISA slot. Also, MSI released a modern motherboard with one ISA slot in 2020. The PC/104 bus, used in industrial and embedded applications,

1577-566: Is in the ATSC "Digital Audio Compression (AC-3) (E-AC-3) Standard" , section 5.4. AC3 was covered by patents that expired in March 2017. Patents were used to ask to pay a commercial license to publish an application that decodes AC3. This led some audio app developers to ban AC3 from their apps, although the open source VLC media player supported AC-3 audio without having paid a patent license fee. In Dolby's 2005 original and amended S-1 filings with

1660-406: Is intended to be mixed with the primary audio soundtrack in the Blu-ray Disc player. Dolby AC-4 is an audio compression standard supporting multiple audio channels and/or audio objects. Support for 5.1 channel audio is mandatory and additional channels up to 7.1.4 are optional. AC-4 provides a 50% reduction in bit rate over AC-3/ Dolby Digital Plus . Dolby TrueHD, developed by Dolby Laboratories,

1743-511: Is not backward compatible with existing AC-3 hardware, though E-AC-3 codecs generally are capable of transcoding to AC-3 for equipment connected via S/PDIF . E-AC-3 decoders can also decode AC-3 bitstreams. The fourth generation Apple TV supports E-AC-3. The discontinued HD DVD system directly supported E-AC-3. Blu-ray Disc offers E-AC-3 as an option to graft added channels onto an otherwise 5.1 AC-3 stream, as well as for delivery of secondary audio content (e.g. director's commentary) that

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1826-414: Is now fairly hard to find. Some XT-IDE adapters were available as 8-bit ISA cards, and XTA sockets were also present on the motherboards of Amstrad 's later XT clones as well as a short-lived line of Philips units. The XTA pinout was very similar to ATA, but only eight data lines and two address lines were used, and the physical device registers had completely different meanings. A few hard drives (such as

1909-493: Is reduced, decreasing the amount of noise-inducing signal travel. This also made it possible to reduce the size of AWE64's board noticeably, compared to AWE32. The Sound Blaster AWE32 boards allowed sample RAM expansion through the installation of 30-pin fast-page DRAM SIMMs . These SIMMs were commodity items during the time of AWE32 and AWE64, because they were used for many other applications, including plain system RAM. As such, Creative had no control over their sale. So, with

1992-452: Is the name for a family of audio compression technologies developed by Dolby Laboratories . Called Dolby Stereo Digital until 1995 , it is lossy compression (except for Dolby TrueHD). The first use of Dolby Digital was to provide digital sound in cinemas from 35 mm film prints. It has since also been used for TV broadcast, radio broadcast via satellite, digital video streaming, DVDs , Blu-ray discs and game consoles. Dolby AC-3

2075-453: Is used on DVD-Video and other purely digital media, like home cinema. In this format, the AC-3 bitstream is interleaved with the video and control bitstreams. The system is used in bandwidth-limited applications other than DVD-Video, such as digital TV. The AC-3 standard allows a maximum coded bit rate of 640 kbit/s. 35 mm film prints use a fixed rate of 320 kbit/s, which is the same as

2158-496: The Extended Industry Standard Architecture (EISA) and the later VESA Local Bus (VLB). VLB used some electronic parts originally intended for MCA because component manufacturers already were equipped to manufacture them. Both EISA and VLB were backward-compatible expansions of the AT (ISA) bus. Users of ISA-based machines had to know special information about the hardware they were adding to

2241-465: The MP3 standard (1993) and AAC (1997). Batman Returns was the very first movie to be announced as using Dolby SR-D (Spectral Recording-Digital) technology when it premiered in all selected movie theaters in the summer of 1992. Dolby Digital cinema soundtracks are optically recorded on a 35 mm release print using sequential data blocks placed between every perforation hole on the soundtrack side of

2324-467: The Seagate ST351A/X) could support either type of interface, selected with a jumper. Many later AT (and AT successor) motherboards had no integrated hard drive interface but relied on a separate hard drive interface plugged into an ISA/EISA/VLB slot. There were even a few 80486-based units shipped with MFM/RLL interfaces and drives instead of the increasingly common AT-IDE. Commodore built

2407-650: The University of Surrey in 1987. Dolby Laboratories adapted the MDCT algorithm along with perceptual coding principles to develop the AC-3 audio format for cinema . The AC-3 format was released as the Dolby Digital standard in February 1991. Dolby Digital was the earliest MDCT-based audio compression standard released, and was followed by others for home and portable usage, such as Sony 's ATRAC (1992),

2490-465: The Xbox game console and certain nForce2 motherboards, used an early form of this technology. DDL is available on motherboards with codecs such as Realtek 's ALC882D, ALC888DD and ALC888H. Other examples include some C-Media PCI sound cards and Creative Labs' X-Fi and Z series sound cards, whose drivers have enabled support for DDL. NVIDIA later decided to drop DDL support in their motherboards due to

2573-494: The signal-to-noise ratio and overall signal quality compared to the frequently quite noisy AWE32 and Sound Blaster 16 boards. This improvement is most notable with the AWE64 Gold, because of its superior gold plated RCA connector outputs. The improvement also comes from increased integration of components on AWE64 compared to its predecessors. Increased integration means the board can be simpler and trace routing to components

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2656-509: The subwoofer driven low-frequency effects . Mono and stereo modes are also supported. AC-3 supports audio sample rates up to 48 kHz. In 1991, a limited experimental release of Star Trek VI: The Undiscovered Country in Dolby Digital played in 3 US theatres. In 1992, Batman Returns was the very first movie to be released and presented in Dolby Digital. In 1995, the LaserDisc version of Clear and Present Danger featured

2739-537: The 'Xtreme Audio' and its derivatives such as Prodigy 7.1e, which is incapable of DDL in hardware). X-Fi 's case differs. While they forgot about the plan, programmer Daniel Kawakami made a hot issue by applying Auzentech Prelude DDL module back to Creative X-Fi cards by disguising the hardware identity as Auzentech Prelude. Creative Labs alleged Kawakami violated their intellectual property and demanded he cease distributing his modified drivers. Eventually Creative struck an agreement with Dolby Laboratories regarding

2822-579: The 5.1 channel configuration, Dolby Digital allows a number of different channel selections. The options are: These configurations optionally include the extra low-frequency effects (LFE) channel, but only if at least three channels are present. The last two with stereo surrounds can optionally use Dolby Digital EX matrix encoding to add an extra Rear Surround channel, indicated via a 2-bit flag. Many Dolby Digital decoders are equipped with downmixing to distribute encoded channels to speakers. This includes such functions as playing surround information through

2905-418: The 5.1 mix, much like the front center channel on Dolby Pro Logic encoded stereo soundtracks. The result can be played without loss of information on standard 5.1 systems, or played in 6.1 or 7.1 on systems with Surround EX decoding and added speakers. A number of DVDs have a Dolby Digital Surround EX audio option. The theater version of Dolby Digital Surround EX was introduced in 1999, when Dolby and THX ,

2988-523: The 8-bit version as a buffered interface to the motherboard buses of the Intel 8088 (16/8 bit) CPU in the IBM PC and PC/XT, augmented with prioritized interrupts and DMA channels. The 16-bit version was an upgrade for the motherboard buses of the Intel 80286 CPU (and expanded interrupt and DMA facilities) used in the IBM AT, with improved support for bus mastering. The ISA bus was therefore synchronous with

3071-575: The AT bus's performance but in 1987, IBM replaced the AT bus with its proprietary Micro Channel Architecture (MCA). MCA overcame many of the limitations then apparent in ISA but was also an effort by IBM to regain control of the PC architecture and the PC market. MCA was far more advanced than ISA and had many features that would later appear in PCI. However, MCA was also a closed standard whereas IBM had released full specifications and circuit schematics for ISA. Computer manufacturers responded to MCA by developing

3154-451: The ATA standard (up to 133 MB/s for ATA-6, the latest.) In most forms, ATA ran much faster than ISA, provided it was connected directly to a local bus (e.g. southbridge-integrated IDE interfaces) faster than the ISA bus. Before the 16-bit ATA/IDE interface, there was an 8-bit XT-IDE (also known as XTA) interface for hard disks. It was not nearly as popular as ATA has become, and XT-IDE hardware

3237-403: The AWE64, Creative moved to proprietary RAM expansion modules which only they manufactured and sold. These memory boards were priced rather high. Their limited production also has made it quite difficult to expand an AWE64's RAM capacity since the AWE64 left production. AWE64, in the end, was basically a revision of the AWE32. Quality of components and output was improved and cost of manufacturing

3320-516: The CPU clock of the 80286 in IBM PC/AT computers, which was 6 MHz in the first models and 8 MHz in later models. The IBM RT PC also used the 16-bit bus. ISA was also used in some non-IBM compatible machines such as Motorola 68k -based Apollo (68020) and Amiga 3000 (68030) workstations, the short-lived AT&T Hobbit and the later PowerPC -based BeBox . Companies like Dell improved

3403-402: The CPU clock until sophisticated buffering methods were implemented by chipsets to interface ISA to much faster CPUs. ISA was designed to connect peripheral cards to the motherboard and allows for bus mastering . Only the first 16 MB of main memory is addressable. The original 8-bit bus ran from the 4.77 MHz clock of the 8088 CPU in the IBM PC and PC/XT. The original 16-bit bus ran from

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3486-504: The DDL pack at no added cost. E-AC-3 (Dolby Digital Plus) is an enhanced coding system based on the AC-3 codec . It offers increased bitrates (up to 6.144 Mbit/s), support for even more audio channels (up to 15.1 discrete channels in the future), and improved coding techniques (only at low data rates) to reduce compression artifacts , enabling lower data rates than those supported by AC-3 (e.g. 5.1-channel audio at 256 kbit/s). It

3569-704: The Dolby license royalty by arranging that the licensing cost be folded into the purchase price of the Creative X-Fi PCI cards rather than as a royalty paid by Creative themselves. Based on the agreement, in September 2008 Creative began selling the Dolby Digital Live packs enabling Dolby Digital Live on Creative's X-Fi PCI series of sound cards. It can be purchased and downloaded from Creative. Subsequently, Creative added their DTS Connect pack to

3652-556: The LaserDisc world AC3RF is the term widely placed on connectors of players that support Dolby Digital. Specific demodulators and receivers from the LaserDisc era (1990s thru early 2000s) also include placement of this term on connectors. LaserDisc titles with Dolby Digital tracks often have the THX logo on their covers. The data layout of AC-3 is described by simplified " C -like" language in official specifications. An AC-3 stream

3735-499: The P996 specification. However, despite books being published on the P996 specification, it never officially progressed past draft status. There still is an existing user base with old computers, so some ISA cards are still manufactured, e.g. with USB ports or complete single-board computers based on modern processors, USB 3.0 , and SATA . Dolby Digital Dolby Digital , originally synonymous with Dolby AC-3 (see below),

3818-515: The PC bus—the AT bus connector was a superset of the PC bus connector. In 1988, the 32-bit EISA standard was proposed by the "Gang of Nine" group of PC-compatible manufacturers that included Compaq. Compaq created the term Industry Standard Architecture (ISA) to replace PC compatible . In the process, they retroactively renamed the AT bus to ISA to avoid infringing IBM's trademark on its PC and PC/AT systems (and to avoid giving their major competitor, IBM, free advertisement). IBM designed

3901-477: The PCMCIA interface is much more complex than ATA. Although most modern computers do not have physical ISA buses, almost all PCs — IA-32 , and x86-64 — have ISA buses allocated in physical address space. Some Southbridges and some CPUs themselves provide services such as temperature monitoring and voltage readings through ISA buses as ISA devices. IEEE started a standardization of the ISA bus in 1985, called

3984-578: The XT-IDE-based peripheral hard drive and memory expansion unit A590 for their Amiga 500 and 500+ computers that also supported a SCSI drive. Later models – the A600 , A1200 , and the Amiga 4000 series – use AT-IDE drives. The PCMCIA specification can be seen as a superset of ATA. The standard for PCMCIA hard disk interfaces, which included PCMCIA flash drives, allows for the mutual configuration of

4067-543: The adapters themselves can no longer be ordered, the design and manufacturing files remain available for download for personal, non-commercial use. As of 2020, Serdaco (Belgium) produces a clone of the SIMMConn. Industry Standard Architecture Originally referred to as the PC bus (8-bit) or AT bus (16-bit), it was also termed I/O Channel by IBM. The ISA term was coined as a retronym by IBM PC clone manufacturers in

4150-734: The address bits and address select signals in the ATA physical interface channel, and all operations of ATA hard disks are performed using the ATA-specified protocols through the ATA command set. The earliest versions of the ATA standard featured a few simple protocols and a basic command set comparable to the command sets of MFM and RLL controllers (which preceded ATA controllers), but the latest ATA standards have much more complex protocols and instruction sets that include optional commands and protocols providing such advanced optional-use features as sizable hidden system storage areas, password security locking, and programmable geometry translation. In

4233-575: The basic command set which became the basis of the ATA interface (and which differed greatly from the interface of IBM's fixed disk controller card for the PC XT). Direct precursors to ATA were third-party ISA hardcards that integrated a hard disk drive (HDD) and a hard disk controller (HDC) onto one card. This was at best awkward and at worst damaging to the motherboard, as ISA slots were not designed to support such heavy devices as HDDs. The next generation of Integrated Drive Electronics drives moved both

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4316-471: The board even more compact, and thus cheaper to build. Unfortunately, during this card's time, the issue of compatibility with older legacy DOS applications accessing PCI audio cards had not been ideally addressed. Creative created a motherboard port called the SB-Link that assisted the PCI bus in working with software that looked for the legacy I/O resources of ISA sound cards. Without this motherboard port,

4399-658: The card was incompatible with DOS software. AWE64 PCI was later followed by the AWE64D, which was a variant of the PCI AWE64 that was developed for OEMs . It again offered the same feature support as other AWE64 cards, including the DOS support issues. The AWE64D was not quite compatible with AWE64 PCI drivers, however, and had to use separate driver packages. An AWE64 Mark II was also designed, and prototype boards and drivers made. This card added 4 speaker surround sound for games, and

4482-534: The cost of involved royalties, leaving an empty space in this regard in the sound cards market. Then in June 2005 came Auzentech , which with its X-Mystique PCI card, provided the first consumer sound card with Dolby Digital Live support. Initially no Creative X-Fi based sound cards supported DDL (2005~2007) but a collaboration of Creative and Auzentech resulted in the development of the Auzentech Prelude,

4565-438: The creation of ISA PnP , a plug-n-play system that used a combination of modifications to hardware, the system BIOS , and operating system software to automatically manage resource allocations. In reality, ISA PnP could be troublesome and did not become well-supported until the architecture was in its final days. A PnP ISA, EISA or VLB device may have a 5-byte EISA ID (3-byte manufacturer ID + 2-byte hex number) to identify

4648-479: The device. For example, CTL0044 corresponds to Creative Sound Blaster 16 / 32 PnP . PCI slots were the first physically incompatible expansion ports to directly squeeze ISA off the motherboard. At first, motherboards were largely ISA, including a few PCI slots. By the mid-1990s, the two slot types were roughly balanced, and ISA slots soon were in the minority of consumer systems. Microsoft 's PC-99 specification recommended that ISA slots be removed entirely, though

4731-574: The drive and controller to a drive bay and used a ribbon cable and a very simple interface board to connect it to an ISA slot. ATA is basically a standardization of this arrangement plus a uniform command structure for software to interface with the HDC within the drive. ATA has since been separated from the ISA bus and connected directly to the local bus, usually by integration into the chipset, for much higher clock rates and data throughput than ISA could support. ATA has clear characteristics of 16-bit ISA, such as

4814-468: The end. In late 2008, even floppy disk drives and serial ports were disappearing, and the extinction of vestigial ISA (by then the LPC bus) from chipsets was on the horizon. PCI slots are rotated compared to their ISA counterparts—PCI cards were essentially inserted upside-down, allowing ISA and PCI connectors to squeeze together on the motherboard. Only one of the two connectors can be used in each slot at

4897-519: The film. A constant bit rate of 320 kbit/s is used. A charge-coupled device (CCD) scanner in the image projector picks up a scanned video image of this area, and a processor correlates the image area and extracts the digital data as an AC-3 bitstream . The data is then decoded into a 5.1 channel audio source. All film prints with Dolby Digital data also have Dolby Stereo analogue soundtracks using Dolby SR noise reduction and such prints are known as Dolby SR-D prints. The analogue soundtrack provides

4980-664: The first X-Fi card to support DDL. Originally planned to extend DDL support to all X-Fi based sound cards (except the 'Xtreme Audio' line which is incapable of DDL hardware implementation), the plan was dropped because Dolby licensing would have required a royalty payment for all X-Fi cards and, problematically, those already sold. In 2008, Creative released the X-Fi Titanium series of sound cards which fully supports Dolby Digital Live while leaving all PCI versions of Creative X-Fi still lacking support for DDL. Since September 2008, all Creative X-Fi based sound cards support DDL (except

5063-486: The front speakers if surround speakers are unavailable, and distributing the center channel to left and right if no center speaker is available. When outputting to separate equipment over a 2-channel connection, a Dolby Digital decoder can optionally encode the output using Dolby Surround to preserve surround information. The '.1' in 5.1, 7.1 etc. refers to the LFE channel, which is also a discrete channel. Dolby Digital audio

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5146-441: The late 1980s or early 1990s as a reaction to IBM attempts to replace the AT bus with its new and incompatible Micro Channel architecture . The 16-bit ISA bus was also used with 32-bit processors for several years. An attempt to extend it to 32 bits, called Extended Industry Standard Architecture (EISA), was not very successful, however. Later buses such as VESA Local Bus and PCI were used instead, often along with ISA slots on

5229-513: The maximum bit rate for 2-channel MP3 . DVD-Video discs are limited to 448 kbit/s, although many players can successfully play higher-rate bitstreams (which are non-compliant with the DVD specification). HD DVD limits AC-3 to 448 kbit/s. ATSC and digital cable standards limit AC-3 to 448 kbit/s. Blu-ray Disc, the PlayStation 3 and the Xbox game console can output an AC-3 signal at

5312-449: The mid-1990s, the ATA host controller (usually integrated into the chipset) was moved to PCI form. A further deviation between ISA and ATA is that while the ISA bus remained locked into a single standard clock rate (for backward hardware compatibility), the ATA interface offered many different speed modes, could select among them to match the maximum speed supported by the attached drives, and kept adding faster speeds with later versions of

5395-583: The original IBM AT) are likely to stick around for a while. As explained in the History section, ISA was the basis for development of the ATA interface, used for ATA (a.k.a. IDE) hard disks. Physically, ATA is essentially a simple subset of ISA, with 16 data bits, support for exactly one IRQ and one DMA channel, and 3 address bits. To this ISA subset, ATA adds two IDE address select ("chip select") lines (i.e. address decodes, effectively equivalent to address bits) and

5478-496: The port and the drive in an ATA mode. As a de facto extension, most PCMCIA flash drives additionally allow for a simple ATA mode that is enabled by pulling a single pin low, so that PCMCIA hardware and firmware are unnecessary to use them as an ATA drive connected to an ATA port. PCMCIA flash drive to ATA adapters are thus simple and inexpensive but are not guaranteed to work with any and every standard PCMCIA flash drive. Further, such adapters cannot be used as generic PCMCIA ports, as

5561-431: The projector head. However, for new projectors it made sense to use dual analogue/digital soundheads in the normal optical soundhead position under the projector head. To allow for the dual-soundhead arrangement the data is recorded 26 frames ahead of the picture. If a penthouse soundhead is used, the data must be delayed in the processor for the required amount of time, around 2 seconds. This delay can be adjusted in steps of

5644-635: The same mainboard . Derivatives of the AT bus structure were and still are used in ATA/IDE , the PCMCIA standard, CompactFlash , the PC/104 bus, and internally within Super I/O chips. Even though ISA disappeared from consumer desktops many years ago, it is still used in industrial PCs , where certain specialized expansion cards that never transitioned to PCI and PCI Express are used. The original PC bus

5727-487: The same time, up to 4 devices may use one 8-bit DMA channel each, while up to 3 devices can use one 16-bit DMA channel each. Originally, the bus clock was synchronous with the CPU clock, resulting in varying bus clock frequencies among the many different IBM clones on the market (sometimes as high as 16 or 20 MHz), leading to software or electrical timing problems for certain ISA cards at bus speeds they were not designed for. Later motherboards or integrated chipsets used

5810-401: The standard 5.1 channel Dolby Digital codec in the form of matrixed rear channels, creating 6.1 or 7.1 channel output. It provides an economical and backwards-compatible means for 5.1 soundtracks to carry a sixth, center back surround channel for improved localization of effects. The extra surround channel is matrix encoded onto the discrete left surround and right surround channels of

5893-447: The standard) or simply Dolby Digital ( DD ), is the common version containing up to six discrete channels of sound. Before 1996 it was marketed as Dolby Surround AC-3 , Dolby Stereo Digital , and Dolby SRD . The most elaborate mode of this codec in common use involves five channels for normal-range speakers ( 20 Hz – 20,000 Hz ) (right, center, left, right surround, left surround) and one channel ( 20 Hz – 120 Hz allotted audio) for

5976-555: The system CPU. The technology, called WaveGuide , synthesizes the instrument sounds rather than using stored instrument patches like the hardware voices. This not only demands more processing power from the host system, but also is not of equal quality to available SoundFonts . The inability to adjust synthesis parameters, unlike with the hardware portion of the AWE64, also limited the WaveGuide function's usefulness. Another improvement comes from better on-board circuitry that increases

6059-447: The system architecture still required ISA to be present in some vestigial way internally to handle the floppy drive , serial ports , etc., which was why the software compatible LPC bus was created. ISA slots remained for a few more years, and towards the turn of the century it was common to see systems with an Accelerated Graphics Port (AGP) sitting near the central processing unit , an array of PCI slots, and one or two ISA slots near

6142-478: The system. While a handful of devices were essentially plug-n-play , this was rare. Users frequently had to configure parameters when adding a new device, such as the IRQ line, I/O address , or DMA channel. MCA had done away with this complication and PCI actually incorporated many of the ideas first explored with MCA, though it was more directly descended from EISA. This trouble with configuration eventually led to

6225-674: The time between perforations, (approximately 10.4 ms). Dolby Digital remains the predominant sound mixing format for movies, despite the introduction of Dolby Surround 7.1 and Dolby Atmos in 2010 and 2012, respectively. Dolby Digital has similar technologies, included in Dolby Digital EX, Dolby Digital Live, Dolby Digital Plus, Dolby Digital Surround EX, Dolby Digital Recording, Dolby Digital Cinema, Dolby Digital Stereo Creator and Dolby Digital 5.1 Creator. Dolby AC-3 (a backronym for Audio Codec 3, Advanced Codec 3, or Acoustic Coder 3), also known as ATSC A/52 (name of

6308-490: The two sockets into one unit. These can be found in almost every AT-class PC manufactured after the mid-1980s. The ISA slot connector is typically black (distinguishing it from the brown EISA connectors and white PCI connectors). Motherboard devices have dedicated IRQs (not present in the slots). 16-bit devices can use either PC-bus or PC/AT-bus IRQs. It is therefore possible to connect up to 6 devices that use one 8-bit IRQ each and up to 5 devices that use one 16-bit IRQ each. At

6391-492: The very first home theater Dolby Digital mix, quickly followed by True Lies , Stargate , Forrest Gump , and Interview with the Vampire among others. Dolby Digital Surround EX (sometimes shortened to Dolby Digital EX) is similar to Dolby's earlier Pro Logic format, which utilized matrix technology to add a center surround channel and single rear surround channel to stereo soundtracks. EX adds an extension to

6474-583: Was developed by a team led by Mark Dean at IBM as part of the IBM PC project in 1981. It was an 8-bit bus based on the I/O bus of the IBM System/23 Datamaster system - it used the same physical connector, and a similar signal protocol and pinout. A 16-bit version, the IBM AT bus, was introduced with the release of the IBM PC/AT in 1984. The AT bus was a mostly backward-compatible extension of

6557-545: Was introduced with the IBM PC/AT . This bus was officially termed I/O Channel by IBM. It extends the XT-bus by adding a second shorter edge connector in-line with the eight-bit XT-bus connector, which is unchanged, retaining compatibility with most 8-bit cards. The second connector adds four additional address lines for a total of 24, and 8 additional data lines for a total of 16. It also adds new interrupt lines connected to

6640-439: Was later introduced, and it can carry uncompressed multichannel PCM, lossless compressed multichannel audio, and lossy compressed digital audio. However, Dolby Digital Live is still useful with HDMI to allow transport of multichannel audio over HDMI to devices that are unable to handle uncompressed multichannel PCM. Dolby Digital Live is available in sound cards using various manufacturers' audio chipsets. The SoundStorm , used for

6723-441: Was lessened. Functionality of the hardware was nearly identical. The boards were based around the AWE32's E-mu 8000 sample-based synthesis chipset, E-mu effects processor, and a Creative audio DSP and codec for digital sound playback. The AWE64 came in two versions initially: A standard version, later re-branded as Value (with 512   KB of RAM ), and a Gold version (with 4   MB of RAM, high quality 20-bit DAC and

6806-494: Was limited to 128 KiB sections, leading to problems when mixing 8- and 16-bit cards as they could not co-exist in the same 128 KiB area. This is because the MEMCS16 line is required to be set based on the value of LA17-23 only. ISA is still used today for specialized industrial purposes. In 2008, IEI Technologies released a modern motherboard for Intel Core 2 Duo processors which, in addition to other special I/O features,

6889-501: Was the original version of the Dolby Digital codec. The basis of the Dolby AC-3 multi-channel audio coding standard is the modified discrete cosine transform (MDCT), a lossy audio compression algorithm. It is a modification of the discrete cosine transform (DCT) algorithm, which was proposed by Nasir Ahmed in 1972 for image compression . The DCT was adapted into the MDCT by J.P. Princen, A.W. Johnson and Alan B. Bradley at

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