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1989,1991 - The first Sound Blasters

Sound Blaster (1989)

Sound Blaster 1.5 with CMS chips
Sound Blaster 1.5 with CMS chips
Creative Labs (CL) quickly realized that their Game Blaster was sentenced to death. The support was not outstanding, and most games did not even make use if its effect channels.
So they went to the game industry, asked here and asked there. And got the unambiguous result that a sound card, besides being able to play music, should also be able to play samples. Maybe because this was a killer feature, or because they wanted to fight AdLib, they codenamed it "Killer card", which was named "Sound Blaster" when it came to market.

In version 1.0 it was equipped with a DSP (here "Digital Sound Processor") capable of playing back 22.05 Khz 8 bits Mono sound and 13 Khz 8 bits recording, CMS chips for compatibility with their own Game Blaster and - most important of all - with a Yamaha OPL2. With the latter they entered into direct competition with AdLib. This was supposedly only possible thanks to Microsoft, which persuaded Yamaha to bring the OPL2 on the free market - until then, AdLib was exclusive partner and buyer!

Production in Singapore made the card cheaper to produce than the Canadian produced AdLib, and AdLib was pushed quickly off the market. According to Rich Heimlich, at this time owner of the largest third party game QA company "Top Star" with contacts to both game and hardware industry, Creative has achieved much of its success not because of its sampling abilities, but thanks to its integrated game port: "At the time both cards sold for $239 to $289 US. However, the Sound Blaster gave the audience HUGE, immediately beneficial option with the game port. At that time most PC's came with just 3 expansion ports. Using one of those precious slots for a game port was hard to accept. Also, game port cards (made by companies like Kraft) sold for $50 alone."
According to him, it took the Sound Blaster about two years to push AdLib from the market, but the sampling part was merely a nice side effect that was initially not being supported by games. The later large market share then made it easy for game developers to support sampling.

SB 2.01 with empty CMS sockets
SB 2.01 with empty CMS sockets

Under the "bonnet", it looked very chaotic. Seemingly, they were in trouble getting the card fast to the market. This resulted in a difficultly programmable DSP (although one product of this house should later top this), and a mediocre sound rendering, which often made itself noticeable by crackling. But after all - they had brought the first consumer card on market that allowed playback of digital samples!

As a technical side note, the crackling happened for specific reason: The card was not directly supporting streaming sound playback, and was better at playing single samples - but especially later games opted for streaming sound playback.
Data was sent to the card in blocks via DMA (Direct Memory Access). After one block reached its end, you had to inform the card that another block will come, and simultaneously, you had to suggest this situation also again to the DMA controller. This led to considerable gaps, in which simply nothing was played, especially on slower systems. Stopping sound data and its further playing led to partly considerable level fluctuations, which we then perceive as crackling.

Another problem, often overlooked by developers, was an only very coarse adjustment of the playback frequency. Placing 22.05 Khz (half of CD sampling frequenc) precisely was not possible. Many developers overlooked this, and so music often is returned too slowly. Example: Epic Pinball - SB Pro compared with Ultrasound.
This problem existed until the Sound Blaster Pro and was solved later with a better interface.

The Killer card

Sound Blaster prototype - picture by Chris Byrne
Sound Blaster prototype - picture by Chris Byrne
This is a prototype card that has been sent to Headstart Computers in about 1989. The company made low end computers bundled with software, which supposedly made it an interesting candidate for Creative Labs. The company later went under, without ever releasing a PC with a Sound Blaster.
The card pictured had a DSP version of 1.03 (retail CT1320 came out with 1.05), and, according to Chris Byrne, who owned it a while and supplied its picture, it is noisier than a retail card (which already is quite noisy). Its back side contains a prototype notice, a 1989 copyright and some manually soldered wires (see link). Also notice the already covered Intel MCS-51 chip in the prototype.

Further versions of the card followed little later. Version 1.5 was an economy version: the CMS chips for Game Blaster compability were optional, instead there were two empty sockets.
Version 2.0 on the other hand saved another chip, that was also intended for CMS (a standard chip, but programmed by CL). Simultaneously, they optimized the circuit board layout, which now worked with clearly less chips. Most importantly, however, was the DMA autoinit mode that finally enabled the card to play continuously, therefore without interruption and crackling! Its last incarnation was version 2.01, which made sound playback with 44.1 Khz sampling rates (CD sampling frequency, but still only 8 bits and mono) possible.
To achieve this, Creative introduced the "Hispeed Mode", which is a nice description of what actually happens: the DSP, by the way an Intel MCS-51, was so heavily loaded in this mode (used for anything above 23 Khz), that it didn't accept any commands from outside anymore, and the rendering could only be stopped with a reset of the complete DSP!

All these improvements brought some alterations to the interface of the DSP - one of the reasons, why other companies had so heavy problems really being 100 percent compatible to this card. While malicious gossip says, this happened in order to stop competitors, I claim that this is also a result of incompetence on one hand, but also time pressure on the developers side at Creative Labs on the other hand.

Purchasing it used

The original Sound Blasters are a bit rare, but you can find them. If you find them, they tend to be expensive, especially the first version. You may get the second (shorter) version without CMS chips for less.
There are reasons to purchase especially this Sound Blaster: You only have an 8 bits ISA slot, you want CMS compatibility (with its first version) or you just love to hear the noise of your ISA bus!


os2museumThe DSP was in reality an Intel chip
ImgurPicture of the Killer card prototype
Vintage Computer FederationThread about the killer card origin
MobygamesGames supporting the Sound Blaster

Sound Blaster Pro (1991)

Sound Blaster Pro 1.0
Sound Blaster Pro 1.0
A further development of the original Sound Blaster was the Sound Blaster Pro. Its main advantage to the Sound Blaster 2.0 was its the ability to play and record stereo. The latter now even at 22.05 Khz!
The DSP still only worked with 8 bits samples, but the original OPL2 received company: a second chip of this kind guaranteed stereo FM music playback - although this was rarely used by games. Why can it do mono at 44.1 KHz, but stereo only at the half? Well, it was not only an issue of the DSP used, which was maxed out at 44.1 KHz, but the card also employed a "dirty" trick: To cut costs, it still only used a mono DAC! To achieve stereo playback, the mono signal was then demuxed - essentially taking one sample for the left, the other for the right. This halves the 44.1 KHz mono to 22.05 KHz for stereo playback.

Sound Blaster Pro 2.0
Sound Blaster Pro 2.0
This card went through multiple revisions, while every revision brought improvements to the interference coming from bus transfers (one could follow his mouse movements, keyboard typing and all other live at the speakers), and very possibly also with fixes for several bugs in hardware and chipset design.
The Sound Blaster Pro 2 replaced the two OPL2 were replaced by an OPL3. It was backwards compatible with OPL2, played stereo with 18 voices with very simple panning (l/r/center), brought 4 new waveforms and supported synthesizing with 4 operators - instead of the only 2 possible with the OPL2.

Also with this card, Creative Labs obviously was a little hasty, possibly to have a competitor for the Pro Audio Spectrum in time. One notable example: Some may remember the "reverse stereo" option of some games.
According to some voices the first two revisions of the card swallowed (maybe also all, nobody exactly knows it) the first data byte, therefore the left channel, and then happily started playing on the left side - but with the second byte, hence the right channel!
Creative Labs recognized this defect and introduced an obscure code snippet, to send one byte to the card, in their programming examples with the headline "enable stereo playback"...

Purchasing it used

The Sound Blaster Pro 2 is not rare, the first version is a bit harder to get. The prices for the second version are reasonable, usually below the first Sound Blasters, and there's no need to go for the first Pro version unless you absolutely want or need it. Only few games supported the two OPL2 chips.
There's one distinctive reason you'd want to get a Sound Blaster Pro: You want 100% Sound Blaster and Sound Blaster Pro (hence stereo) compability. The latter is important: the SB16 is NOT Sound Blaster Pro compatible and cannot play back stereo in SB Pro mode. If your game only supports stereo through an SB Pro, your choice is clear!


Epic Pinball[OGG] [MP3]MOD-Playback, here the game interpolates by software
Descent[OGG] [MP3]Descent I intro - OPL3 sounds like OPL2 in stereo...


FAQSysProgramming the OPL3
MobygamesGames supporting the Sound Blaster Pro
WikipediaThe Yamaha OPL3

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