Science Fair Project Encyclopedia
The Sound Blaster family of sound cards was for many years the de facto standard for audio on the IBM PC compatible system platform, beforePC audio became commoditized. 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 synthesiser 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, presumably from Intel. 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" 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.
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 provided better support for multitasking operating systems, presumably thanks to the introduction of its own timer interrupt. It was the earliest Sound Blaster supported by OS/2.
Improved quality: stereo and 16 bits
Sound Blaster Pro
The Sound Blaster Pro (May 1991) added stereo capabilities, but not yet at CD quality level, since it still had only 8-bit sampling. The first version of the Pro also used two YM3812 chips (one for left audio channel and the other one for the right one; both chips had to be programmed identically to get sound in the middle). Version 2.0 switched to the improved Yamaha YMF262 chip, also known as OPL3. MIDI support became full-duplex and offered timestamping features, but was not yet industry-standard MPU-401 compatible.
Sound Blaster 16
The next model, Sound Blaster 16 (June 1992) introduced 16-bit sampling to the Sound Blaster line. The cards also featured a connector for add-on daughterboards with wavetable 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.
Sound Blasters with onboard wavetable synthesis
Sound Blaster AWE32
The Sound Blaster AWE32 (March 1994) introduced the EMU8000 processor which supported 30-channel wavetable synthesis. The AWE32 didn't use its General MIDI port to access the wavetable module—Creative decided to use a nonstandard 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 OPL3 FM synthesis. Its usage on Windows was simplified by the fact that Windows 3.1 had drivers which made the FM synthesizer appear like just another MIDI peripheral, on its own MIDI interface.
The Sound Blaster AWE32 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), and the lack of an integrated controller (an ASIC). The AWE32 included two sound processors (the Creative controller and the EMU8000), an analog processing section with resonant filtering, a Panasonic/Sony/Mitsumi CD-ROM interface (for accessing old, non-ATAPI CD-ROM drives which were still in use at the time), 512 KB built-in memory, and two 30-pin SIMM slots (with their own memory controller) for adding sample memory. The AWE32 supported up to 16 MB of additional SIMM memory.
Before the advent of ATAPI interfaces for CD-ROM drives, three main manufacturers—Panasonic/Matsushita, Mitsumi, and Sony—each had their own interfaces with differing pin connections. Modern ATAPI drives are connected to the IDE controller (on the motherboard or an expansion controller), but these older drives had to be accessed via special interfaces which were typically included on sound cards at the time.
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 (sans the old CD-ROM interface), but has a few notable improvements, including support for more midi voices simultaneously and a higher polyphony count. The AWE64 came in 3 versions: A Value version (with 512KB of RAM), a Standard version (with 1MB of RAM), and a Gold version (with 4 MB of RAM and SPDIF ports). 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 a 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. This was followed by the AWE64D, which was a variant of the PCI AWE64 that was developed for OEMs. It offered the same features as the retail PCI AWE64, but has an architecture that was distinct enough to prevent the standard PCI AWE64 drivers from working with it.
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.
Sound Blaster Live!
Sound Blaster Live! (August 1998) saw the introduction of the EMU10K1 processor, a 2.44 million transistor DSP. The EMU10K1 featured DirectSound acceleration, General MIDI wavetable output, EAX (environmental audio extensions, which competed with A3D before the demise of the latter), a high-quality 64-voice wavetable synthesizer, and 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 is actually a 32-bit programmable processor (with 1 KB of instruction memory). Effect algorithms are created by a development system that integrates into Microsoft Developer Studio. The effects are written in a language similar to C, and compiled into native FX8010 object code by its compiler, fxasm.
The Sound Blaster Live! features higher audio quality than previous Sound Blasters, as it processes the sound digitally at every stage. It has 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) is first upsampled to 48 kHz and then downsampled. In a production environment with a Sound Blaster Live!, it is generally recommended to use 48 kHz sampling to maintain sound integrity. The later versions of the Sound Blaster Live! featured support for 5.1 surround sound.
Sound Blaster Audigy
The Sound Blaster Audigy (August 2001) features the Audigy processor and supports 24-bit play-back at up to 96 kHz and recording at up to 48 kHz. The Audigy can process up to 4 EAX environments simultaneously, and supports up to 5.1 speakers.
Sound Blaster Audigy 2
The Sound Blaster Audigy 2 (September 2002) features the Audigy 2 processor and supports 24-bit play-back at up to 192 kHz and recording at up to 96 kHz. The Audigy 2 supports up to 6.1 speakers and has improved signal-to-noise ratio (SNR) over the Audigy (106 vs. 100). It also features built-in Dolby Digital 5.1 EX (which is technically 7.1) decoding for improved DVD play-back.
Sound Blaster Audigy 2 ZS, Sound Blaster Audigy 2 Value, and Sound Blaster Live! 24-bit
The Sound Blaster Audigy 2 ZS, improves upon the Audigy 2 by having a slightly improved SNR (108 vs. 106 dB) and adds built-in DTS-ES (Extended Surround) for improved DVD play-back. The Audigy 2 ZS supports up to 7.1 speakers.
The Sound Blaster Audigy 2 Value is a stripped down version of the Audigy 2 ZS, with an SNR of 106 dB, no GamePort, and no DTS-ES 6.1 playback.
The Sound Blaster Live! 24-bit is not actually a member of the Sound Blaster Live! family, but is a further stripped down version of the Audigy 2 Value, with an SNR of 100 dB, no advanced resolution DVD-Audio Playback, and no Dolby Digital 5.1 or Dolby Digital EX 6.1 playback.
The Soundblaster Audigy 2 NX is an external USB soundcard, supporting 24 bit playback
Sound Blaster Audigy 4 Pro
The latest incarnation, the Sound Blaster Audigy 4 Pro improves on the Sound Blaster Audigy 2 ZS by improving the SNR to 113 dB. It serves as a stepping stone between the Audigy 2 ZS and the Zenith.
Sound Blaster Zenith
Creative's next generation sound card will be called the Sound Blaster Zenith. Little is currently known about the Zenith, but it is said to be based on PCI Express x1.
- Programming the AdLib/Sound Blaster FM Music Chips
- Programmer's Guide to Yamaha YMF 262/OPL3 FM Music Synthesizer
- Setting the BLASTER environment variable
- Creative Labs - History and Milestones
- Inside the EMU10K1
- Old Mitsumi proprietary CD-ROM interface pinout
- kX Project (independent WDM driver for EMU10K1 and EMU10K2-based soundcards)
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