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The Sound Blaster family of Sound Card s was for many years the De Facto standard for audio on the IBM PC Compatible System Platform , before PC audio became commoditized, and backward-compatibility became less of a feature. The creator of Sound Blaster is the Singapore -based firm Creative Labs . THE PRE-SOUND BLASTER YEARS The history of Creative Labs sound boards started with the release of the ''Creative Music System'' ("C/MS") board in August 1987 . It contained two Philips SAA 1099 circuits, which, together, provided 12 voices of square-wave ''bee-in-a-box'' stereo sound plus some noise channels. It is interesting to note that these circuits were featured earlier in various popular electronics magazines around the world. For many years Creative tended to use off-the-shelf components and manufacturers' reference designs for their early products. The various integrated circuits had white or black paper sheets fully covering their top thus hiding their identity... On the C/MS board in particular, the Philips chips had white pieces of paper with a fantasy ''CMS-301'' inscription on them; real Creative parts usually had consistent CT ''number'' references. Surprisingly, the board also contained a large 40-pin integrated circuit, bearing a ''CT 1302A CTPL 8708'' serigraphed inscription and looking exactly like the ''DSP'' of the later Sound Blaster. Presumably, it could be used to automate some of the sound operations, like envelope control. A year later, in 1988 , Creative marketed the C/MS via Radio Shack under the name ''Game Blaster''. This card was identical in every way to the precursor C/MS hardware. Creative did not even bother to change any of the labeling or program names on the disks that came with the ''Game Blaster''. FIRST SOUND BLASTERS: THE RIGHT BUNDLE The first board bearing the ''Sound Blaster'' name appeared in November 1989 . In addition to Game Blaster features, it had a 11-voice FM Synthesizer using the Yamaha YM3812 chip, also known as ''OPL2''. It provided perfect compatibility with the competing Adlib sound card, which had gained support in PC games in the preceding years. Creative used the "DSP" acronym to designate the digital audio part of the Sound Blaster. This actually stood for ''Digital SOUND Processor'', rather than for the more common Digital Signal Processor meaning, and was really a simple microcontroller from the Intel MCS-51 family (supplied by Intel and Matra MHS , among others). It could play back monaural Sampled Sound at up to 23 kHz sampling frequency (AM radio quality) and record at up to 12 kHz (slightly better than telephone quality). The sole DSP-like feature of the circuit was ADPCM compression and decompression. The card probably lacked an anti-aliasing filter, as it had a characteristic "metal junk" sound. Finally, it featured a joystick port and a proprietary MIDI interface. This interface lacked simultaneous input and output capabilities, so music software had to use eg. the FM synthesizer in order to play the input received from a MIDI keyboard. It is difficult to tell what microcontroller was used as "DSP" on the first Sound Blaster models, since not only did Creative stick a black label with a fantasy ''(C) COPYRIGHT 1989 CREATIVE LABS, INC. DSP-1321'' inscription on the top, but also carefully scratched two thirds of the plastic surface underneath. Analysis of the device pinout suggests that it was an Intel 8051 microcontroller with a custom mask ROM. The labels on the FM synthesizer circuit and on the companion Yamaha 3014B digital-to-analog converter said ''FM1312'' and ''FM1314'' respectively, but luckily the manufacturer references remained intact below. Later models do away with the obfuscation, and the manufacturer's identity (and, usually, an Intel mask copyright notice) is retained on the DSP. In spite of these limitations, in less than a year, the ''Sound Blaster'' became the top-selling expansion card for the PC. The premature usage of the ''DSP'' word backfired at Creative when they finally included some real digital signal processing features in later Sound Blaster models and were obliged to coin a new term for them, ASP, for Advanced Signal Processing. Sound Blaster 1.5 released in 1990 dropped the "C/MS chips". They could be purchased separately from Creative and inserted into two sockets on the board. This change was probably related to Philips having discontinued the design, and to the lack of enthusiasm among users; the chips could be bought mail-order from Creative until 1993 . Sound Blaster 2.0 added support for auto-init DMA, which assisted in producing a continuous loop of double-buffered sound output. A later revision, 2.01, increased the maximum playback rate to 45KHz (the same maximum as the Sound Blaster Pro, released around the same time). Sound Blaster MCV was a version created for IBM PS/2 model 50 and higher, which had a MicroChannel bus instead of the more traditional ISA one. It was little used. IMPROVED QUALITY: STEREO AND 16 BITS Sound Blaster Pro The ''Sound Blaster Pro'' ( chips (one for left audio channel and the other one for the right one; both chips had to be programmed identically to get mono sound if not using the AdLib compatible interface). Version 2.0 switched to the improved Yamaha YMF262 chip, also known as ''OPL3''. MIDI support became full-duplex and offered time stamping features, but was not yet industry-standard MPU-401 compatible. The Sound Blaster Pro was the first Creative sound card to have a built-in CD-ROM interface. Most had an interface for a Panasonic (Matsushita MKE) drive, prior to the popularity of IDE CD-ROM drives. After the release of the Sound Blaster Pro, Creative also began to sell Multimedia Upgrade Kits, typically including a sound card, Panasonic CD-ROM drive (model 531 for single-speed, or 562 for the later 2x drives), and a large selection of multimedia software titles on the revolutionary CD-ROM media. Sound Blaster cards were also sold to PC manufacturers and third-parties. Many of these so-called ''OEM'' cards have different types of CD-ROM interfaces or other unusual features. Sound Blaster 16 The next model, ''Sound Blaster 16'' ( June 1992 ) introduced 16-bit Digital Audio sampling to the Sound Blaster line. They also, like the older Sound Blasters, natively supported FM Synthesis through a Yamaha OPL-3 chip. The cards also featured a connector for add-on Daughterboard s with Wavetable Synthesis (actually, Sample-based Synthesis ) capabilities complying to the General MIDI standard. Creative offered such daughterboards in their ''Wave Blaster'' line. Finally, the MIDI support now included MPU-401 emulation (in dumb UART mode only, but this was sufficient for most MIDI applications). The Wave Blaster was simply a MIDI peripheral internally connected to the MIDI port, so any PC sequencer software could use it. The ''Sound Blaster 16'' had a socket for an optional Digital Signal Processor dubbed the ''Advanced Signal Processor'' (''ASP'' or later ''CSP''). This chip added some special functionality to SB16, such as speech synthesis through the ''TextAssist'' software, QSound audio Spatialization technology on wave playback, and special general Audio Compression and decompression. The chip was quite unpopular, mainly due to the near-complete lack of industry support. The ''ASP'' chip needed to be directly programmed for or it did absolutely nothing. AWE32 often had the socket as well, but that was the end of the ASP after that. The various models:
SOUND BLASTERS WITH ONBOARD WAVETABLE SYNTHESIS Sound Blaster AWE32 The ''Sound Blaster AWE32'', introduced in March 1994 , was a full-length ISA card, measuring 14 inches (356 mm) in length. It needed to be this large because of the number of features included (the most available at the time). The length of the board was necessary because, at the time, manufacturing technology was incapable of integrating all of the functions into a smaller number of chips. The ''AWE32'' included two distinct audio sections; one being the Creative digital audio section with their audio Codec and optional CSP/ASP chip socket, and the second being the E-mu MIDI synthesizer section. The synthesizer section consisted of several sound processors, the most notable being the EMU8000 synthesizer chip and the EMU8011 effects processor. The two chips provided an advanced wavetable (''Advanced WaveEffects'' a.k.a. AWE) solution that was very flexible and powerful, supporting 30-channel Wavetable Synthesis . The effects processor generated various effects (i.e. Reverb and Chorus ) and Environments on MIDI output, not unlike the later '' EAX '' standard on Live! and newer cards. It can even add effects to the output from the Yamaha OPL-3 's FM synthesis. One of the most stand-out features of ''AWE32'' was its support for the then-burgeoning E-Mu SoundFont standard which allowed users to build custom wavetable sound sets using custom waveform samples. The card included software for building these custom Sound Fonts. All of Creative's subsequent cards, other than the ''Sound Blaster PCI64/128'' series, supported SoundFonts. The Creative digital audio section was basically an entire ''Sound Blaster 16'', and as such, was mostly compatible with Creative's earlier sound cards, including ''Sound Blaster Pro'', ''Sound Blaster 2.0'', and the original ''Sound Blaster''. Its specifications included 16-bit 45 kHz AD / DA conversion with real-time on-board compression / decompression and the Yamaha OPL-3 FM synthesizer chip. AWE32 in general has superior recording and playback characteristics compared to the older SB16. However, compatibility was not always perfect and there were situations where various bugs could arise in games. Many of the ''AWE32'' cards had codecs which supported bass, treble, and gain adjustments through Creative's included mixer software. There were many variants and revisions of the ''AWE32'', however, and not all of them use the same digital audio chipset and features do vary. For example, the ''AWE32'' boards that utilize the ''Vibra'' chip do not have bass and treble adjustments. The ''AWE32'' didn't use its General MIDI (GM) port to access the wavetable module—Creative decided to use a non-standard port. As with the Gravis Ultrasound , software designers had to write special ''AWE32'' support into their programs. To support older software, the ''AWE32'' still featured OPL-3 FM synthesis, and came with the AWEUTIL program which attempted to provide GM/ MT-32 / GS redirection to the native AWE hardware, however the compatibility wasn't great and it used a lot of precious DOS Conventional Memory . Disappointingly, if a game used DOS 32-bit Protected Mode through a non- DPMI compliant DOS Extender , then the MPU-401 emulation could not function and the card could not produce wavetable MIDI unless directly supported by the software. This also affected the Wave Blaster wavetable Daughterboard header. ''AWE32'''s usage in Windows was simplified by the fact that Windows 3.1x had drivers which made the FM Synthesizer appear like just another MIDI peripheral, on its own MIDI interface. Also on ''AWE32'' was a Panasonic / Sony / Mitsumi CD-ROM interface (for accessing old, non- ATAPI CD-ROM drives which were still in use at the time), 1 MB ROM for the default MIDI sound set, 512 KB built-in RAM for custom MIDI sound sets, and two 30-pin SIMM slots (with their own memory controller) for adding sample memory. Later ''AWE32'' revisions received the newer ATAPI interface. The ''AWE32'' supported up to 28 MB of additional SIMM memory; 32 MB could be added to the board, but the synthesizer couldn't address all of it. ''AWE32'' was criticized for its rather noisy analog output. Static, hiss, and pops were not uncommon from the circuitry onboard these cards. ''AWE32'''s name also confused many consumers initially because many believed the number 32 in the name to refer to it's sampling bit depth, as in offering 32-bit audio support, when in reality the value 32 represented the polyphony of its MIDI synthesizers (30 wavetable synthesis voices + the 2 channel mix of the FM synthesizer). Sound Blaster 32 The ''Sound Blaster 32'' (SB32) was a value-oriented offering from Creative, announced on June 6, 1995, designed to fit below the ''AWE32 Value'' in the lineup. The SB32 lacked onboard RAM , had no proprietary CD-ROM connections, no Wave Blaster header, and no CSP port. The boards also used the ''Vibra'' digital audio chip which lacked adjustments for bass, treble, and gain. The SB32 was fully equipped with the same MIDI capabilities (the same EMU8000/EMU8010 combination) as the ''AWE32'', and in fact had the same 30-pin SIMM RAM expansion capability. The board was also fully compatible with the ''AWE32'' option in software and even used the same Windows drivers. Once the SB32 was outfitted with 30-pin SIMMs, it was generally a transparent experience to the more expensive ''AWE32''. Ironically, although the ''Vibra'' chip was designed to be lower cost and less functional, it actually has higher quality output than the chips on many of the older and more expensive AWE cards. Sound Blaster AWE64 The AWE32's successor, the ''Sound Blaster AWE64'' ( November 1996 ), was significantly smaller, being a half-length ISA card (meaning it was only half the length of the AWE32). It offered similar features to the AWE32 (replacing the old CD-ROM interfaces with an IDE compatible one), but has a few notable improvements, including support for greater Polyphony . However, these additional voices were achieved via software Emulation using host CPU resources, rather than being processed on the card, and were thus of questionable value in some situations. The main improvement was better compatibility with older SB models, and an improved ), a Standard version (with 1 MB of RAM), and a Gold version (with 4 MB of RAM and SPDIF ports). The 30-pin SIMM slots were replaced with a proprietary memory format which could be (expensively) purchased from Creative. A fourth version - a PCI version of the AWE64 - was introduced shortly after. It offered the features of the original ISA AWE64, but it had the PCI interface and was built around an ASIC so it had drastically fewer components on the board and ended up being much cheaper than its predecessors. Unfortunately, at this time the issue of compatibility with older legacy DOS applications had not been ideally addressed. Creative created a motherboard port called the SB-Link which assisted the PCI bus in working with software that looked for ISA sound cards. Without this motherboard port the card was incompatible with DOS software. AWE64 PCI was followed by the AWE64D, which was a variant of the PCI AWE64 that was developed for OEM s. It offered the same features as the retail PCI AWE64, but had an architecture that was distinct enough to prevent the standard PCI AWE64 drivers from working with it. AWE64, in the end, was basically a revision of the AWE32. Quality of components and output was improved and cost of manufacturing was lessened. Functionality of the hardware was nearly identical. The boards were based around the AWE32's E-mu 8000 wavetable chipset, E-mu effects processor, and a Creative audio DSP and Codec for digital sound playback. It was regrettable for the consumer that Creative decided to move from standard SIMM RAM expansion to their proprietary modules. Those modules were far more expensive than SIMMs and became very hard to find once the boards were out of production. An AWE64 Mark II was also designed, prototype boards and drivers made. This added 4 speaker surround sound for games, and 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, and though it took up an extra card slot, it didn't actually plug into an ISA socket. The project was dropped in favour of the Live! cards due to the high expense of such a solution, and the aging ISA interface. MULTI-CHANNEL SOUND AND F/X Sound Blaster PCI64 and PCI128 The ''Sound Blaster PCI64'' ( April 1998 ) added four-speaker support ( Quadraphonic sound). Next in that series was the ''Sound Blaster PCI128'' (July 1998). The PCI64/128 were lighter on features than the AWE series, but were basically one-chip cards that were quite inexpensive and attractive to most people who did not require the advanced MIDI features of an AWE card. The cards were actually rebranded Ensoniq AudioPCI 's, a card and technology which was acquired from the merge of E-mu , Creative Labs, and Ensoniq in 1998. Creative did continue development of the drivers and added features. The boards use variants of the Ensoniq ES1370 audio chip (ES1371 and ES1373). These boards were incredibly popular with PC OEM s for their capable functionality and extremely low-cost design. The numerical suffix in the name (64 or 128) represented the number of MIDI channels the card could playback. Unfortunately all of these channels were rather rudimentary in capability and quality, and were entirely software-based since the chip was completely host-driven. And, although the available MIDI sound sets were relatively large for the time (2 MB, 4 MB, and 8 MB), especially compared to the older ROM-based cards, MIDI quality was not superior to many older 2 MB cards. Even Ensoniq's own Soundscape Elite , a card from 1995 with 2 MB sound set ROM, was noteably superior. Somewhat surprising because the AudioPCI was several generations newer technology. These cards do not support SoundFont s. Sound Blaster PCI512 The ''Sound Blaster PCI512'' was basically a lower-priced version of the Sound Blaster Live! Series. It also used the EMU10K1 processor but the firmware could not be flashed unlike the Live! Series to accommodate future EAX extensions. Sound Blaster Live! ''Sound Blaster Live!'' ( August 1998 ) saw the introduction of the EMU10K1 processor, a 2.44 million transistor DSP capable of 1000 MIPS . The EMU10K1 featured DirectSound acceleration, General MIDI wavetable output, ''EAX'' 1.0 and 2.0 ( Environmental Audio Extensions , which competed with A3D before the demise of the latter), a high-quality 64-voice wavetable synthesizer, and integrated the FX8010 DSP chip for real-time digital audio effects processing. A major design change from its predecessor (the EMU8000) was that the EMU10K1 used system memory over the PCI Bus for the wavetable samples, rather than using expensive on-board memory. The FX8010 was a 32-bit programmable processor (with 1 KB of instruction memory). Effect algorithms were created by a development system that integrated into Microsoft Developer Studio. The effects were written in a language similar to C , and compiled into native FX8010 object code by its compiler, ''fxasm''. The ''Sound Blaster Live!'' featured higher audio quality than previous Sound Blasters, as it processed the sound digitally at every stage. It had an internal fixed sample rate of 48 kHz, meaning that any recording done at lower sample rates (such as 44.1 kHz or 32 kHz) was first upsampled to 48 kHz and then downsampled. In a production environment with a Sound Blaster Live!, it was generally recommended to use 48 kHz sampling to maintain sound integrity. Later versions of the Sound Blaster Live! featured support for 4.1 or 5.1 surround sound, but curiously did not support 4.1 surround despite advertising to the contrary. 4.1 surround was actually implemented as 4.0 - i.e. without a dedicated low-frequency channel output; the dubious 4.1 advertising claim actually relied upon the use of an external 4.1 speaker/amplifier implementation that filtered and diverted low frequencies in the quadraphonic signal to a subwoofer. True 4.1 (such as can be configured in most stand-alone DVD players by setting a menu item indicating the absence of a centre speaker) allows the centre signal of a 5.1 source to be blended into the front left and front right output channels, whilst maintaining the dedicated low-frequency-effects channel; this cannot be achieved with the Sound Blaster Live!. The Live! implemented DOS support via Ensoniq 's AudioPCI DOS TSR program. Creative acquired Ensoniq in 1998 and, as part of the deal, utilized this highly-compatible ISA sound card emulator in their cards. In fact, the Live! uses ".ecw" (Ensoniq Concert Wavetable) files for the wavetable emulation in DOS. The program enables support for many standards, such as Sound Blaster 16, General MIDI, AdLib, among others. The original Sound Blaster Live! had a proprietary 9-pin Mini-DIN Connector for digital output that Creative referred to as the "Mini Din." This connector allowed the use of a microphone and digital speakers at the same time. This can not be done with the value and base models of all subsequent Creative sound cards, as they share a single port for S/PDIF digital in/output and microphone connectivity. The Mini Din connection was not included in any subsequent Sound Blaster product, however owners of speaker systems that use this as the only digital input may buy an adapter from Creative. Sound Blaster Audigy The ''Sound Blaster Audigy'' ( August 2001 ) featured the Audigy processor (EMU10K2), an improved version of the EMU10K1 processor that shipped with the Sound Blaster Live! The Audigy could process up to 4 EAX environments simultaneously with its on-chip DSP and native EAX 4.0 ADVANCED HD support, and supported up to 5.1 speakers (but like the Sound Blaster Live!, did not actually support a true 4.1 speaker configuration despite advertising claims to the contrary; 4.1 was actually implemented as 4.0 and relied on the external speaker system/amplifier to extract a sub-woofer signal from the 4.0 output). The audio processor could support up to 64 DirectSound3D sound channels in hardware, up from Live!'s 32 channels. The Audigy's audio transport (DMA engine) was fixed to 16-bit sample precision, and all audio had to be resampled to 48 kHz in order to be rendered through its DSP, or recorded from its DSP. As a result, the card did not support playback of individual audio streams at 24-bit / 96 khz precision through its 24-bit / 96 kHz DAC's, a fact that was not immediately obvious to those examining the spec sheets. Some versions of Audigy also featured an external break out box with connectors for SPDIF , MIDI , SB1394 , analog and optical signals. The significance of the break out box was that it was the first physical sign that the "home studio" was for the first time becoming a mainstream market. Sound Blaster Audigy 2 The ''Sound Blaster Audigy 2'' ( September 2002 ) featured an updated EMU10K2 processor, sometimes referred to as EMU10K2.5, and had an audio transport (DMA engine) that could support playback at 24-bit precision up to 192 kHz (2-channel only. 6.1 limited to 96 kHz) and recording at 24-bit precision up to 96 kHz, thereby overcoming the single biggest criticism of its predecessor. The Audigy 2 supported up to 6.1 speakers (although once again the 4.1 speaker configuration was in reality only 4.0; dedicated subwoofer output was only available with 5.1 and higher) and had improved Signal-to-noise Ratio (SNR) over the Audigy (106 vs. 100 Decibels ( A )). It also featured built-in Dolby Digital 5.1 EX (which is technically 7.1) decoding for improved DVD play-back. A IEEE-1394 ( Firewire ) connector was present in all modifications except Value. Audigy 2's 3D audio capabilities received a boost when compared to its predecessors. Creative created the EAX 4.0 ADVANCED HD standard to coincide with Audigy 2's release. The chip again can process up to 64 DirectSound3D audio channels in hardware. It also has native support for the open source OpenAL audio API . Sound Blaster Audigy 2 ZS, Sound Blaster Audigy 2 Value The ''Sound Blaster Audigy 2 ZS'', improved upon the Audigy 2 by having a slightly improved Signal-to-noise Ratio (108 vs. 106 dB) and added built-in DTS -ES (Extended Surround) for improved DVD playback. The Audigy 2 ZS supported up to 7.1 speakers (although the 4.1 speaker configuration was still in reality only 4.0; a dedicated low-frequency-effects channel output was only available with 5.1 and higher, requiring the presence of a centre speaker). A Cardbus version of ''Audigy 2 ZS'' was also created in Fall 2004, for the notebook market. It had nearly all of the capabilities of the PCI edition, but in a far smaller form factor. Reductions in capability included somewhat limited MIDI capability (compared to the PCI version) and the loss of Firewire . It was the first gaming-oriented sound hardware addon board for notebooks that offered full hardware acceleration of 3D audio along with high-fidelity audio output quality. The card struggled with compatibility due to quality issues with the cardbus host chipsets in many notebooks of the time, a problem also suffered with other companies products, such as Echo Digital Audio Corporation 's Indigo product. The ''Sound Blaster Audigy 2 Value'' was a stripped down version of the Audigy 2 ZS, with an SNR of 106 dB, no GamePort, no IEEE-1394 Firewire connector and no DTS-ES 6.1 playback. The ''Sound Blaster Audigy 2'' NX was an external USB soundcard, supporting 24 bit playback. The ''Sound Blaster Audigy 2 ZS Video Editor'' was an external USB soundcard, which combined audio playback, accelerated video editing and a 4-port USB 2.0 hub in one solution. It featured an accelerated video encoding with DoMiNoFX video processing technologies. The audio system provided THX ® certified sound and 24-bit ADVANCED HD™ in 5.1 or 7.1 surround. Sound Blaster Live! 24-bit The ''Sound Blaster Live! 24-bit'' was not actually a member of the Sound Blaster Live! family, because it lacked the EMU10k1/10k2 processor. It was a stripped down version of the Audigy 2 Value, with an SNR of 100 dB, software based EAX, no advanced resolution DVD-Audio Playback, and no Dolby Digital 5.1 or Dolby Digital EX 6.1 playback. Sound Blaster Audigy 4 Pro The ''Sound Blaster Audigy 4 Pro'' improves on the Sound Blaster Audigy 2 ZS by improving the SNR to 113 dB. It features much of the same core technology as the Audigy 2 ZS (it actually uses the same Audigy 2 chip), it however uses a new external I/O hub. It also allows for simultaneous recording of up to six audio channels in 96 kHz/24 bit. Its output is the same as the audigy 2. 7.1 up to 96 kHz/24bit and stereo at 192 kHz/24bit. Sound Blaster Audigy SE The ''Sound Blaster Audigy SE'' ( January 2006 ) features 24-bit/96 kHz recording and playback with 100dB signal to noise ratio and optional digital output, and recording at up to 16-bit, 48 kHz. It is a stripped down version of the Audigy, software based EAX® ADVANCED HD™ 3.0 (Upgraded to software based EAX® ADVANCED HD™ 4.0 with a Driver update), no advanced resolution DVD-Audio Playback, and no Dolby Digital 5.1 or Dolby Digital EX 6.1 playback. Sound Blaster X-Fi Creative's latest sound card was called the ''X-Fi'' (for "Extreme Fidelity"). It was released in August 2005 and comes in ''XtremeMusic'', ''Platinum'', ''Fatal1ty FPS'' and ''Elite Pro'' configurations. The 130nm core operated at 400 5.0 which supported up to 128 3D-positioned voices with up to four effects applied to each. The X-Fi offered the most powerful mixing capabilities at its time, making it a powerful entry-level card for home musicians. The audio processor on X-Fi was by far the most powerful at the time, offering an extremely robust sample rate conversion ( SRC ) engine in addition to enhanced internal sound channel routing options, and greater 3D audio enhancement capabilities. A significant portion of the audio processing unit was devoted to this resampling engine. The SRC engine was far more capable than previous Creative sound card offerings, a limitation that had been a major thorn in Creative's side. Most digital audio is Sampled at 44.1 kHz, a standard no doubt related to CD Digital Audio , while sound cards were often designed to process audio at 48 kHz. So, the 44.1 kHz audio must be resampled to 48 kHz (Creative's previous cards' DSPs operated at 48 kHz) for the audio DSP to be able to process and affect it. A poor resampling implementation introduces artifacts into the audio which can be heard, and measured as higher Intermodulation Distortion , within higher frequencies (generally 16 kHz and up). X-Fi's resampling engine produces a near-lossless-quality result, far exceeding any known audio card DSP available at the time. This functionality is used not only for simple audio playback, but several other features of the card such as the "Crystalizer". The X-Fi-series had been criticized for the way it had been marketed. The criticism mostly centered around the optional "Crystalizer" functionality - a DSP function which colored the sound to make it seem more clear and vibrant. While there is nothing wrong with that in and of itself, Creative claimed that this crystalizer could turn 16-bit audio into 24-bit quality, which is not just misleading, but also Technically Impossible . Crystalizer is not unlike the many plugins for popular audio players and stereo systems which enhance audio through sophisticated analog/digital modeling. As always, whether or not the effect is beneficial is a qualitative measurement unique to each individual. The X-Fi chip is able to utilize a significant amount of RAM to store sound effects for faster and improved processing, just like the previous E-mu 10K-series and E-mu 8000. This feature, now dubbed ''X-RAM'' by Creative, was claimed to offer quality improvement through audio processing capability enhancement, in addition to further reduction in host system CPU overhead. Driver soft mod Some drivers from the Audigy 2 ZS have been soft-modded by enthusiasts. These are installed on Creative's older cards, including but not limited to SoundBlaster Live!, Audigy, Audigy 2, etc. It has been claimed to offer improved sound quality, hardware acceleration in games, and an overall improvement in the card's performance. Several forum posts across the web have reported favourable results with this technique. SEE ALSO
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