In the early days of computers, “Sound reproduction” on a computer was typically limited to a few beeps and boops. A few early PCs had limited digital audio capabilities, but they were typically limited. The Macintosh was possibly one of the first computers which gained a good market and mind share that had rather advanced sound capabilities. The lowly IBM PC’s “sound capabilities” lagged behind with it’s single basic piezo-electric speaker designed entirely for beep-booping error messages to you like some kind of demented blues singer. The “Sound Card” can trace it’s history to devices like the Creative Music System, The AdLib, and, later, the Creative Game Blaster cards built for the PC. These utilized the Expansion bus to add new capabilities to the system in the form of less beeping and booping and more recognizable music and sound effects.
For quite a number of years Sound Cards were considered “high-end” gaming equipment. Most game titles supported the PC Speaker because it can be assumed present; but many games also supported the sound cards of the day, by using better fidelity sound and even music if a compatible sound card was present.
There is an interesting history in the various sound companies; Creative bought Ensoniq which put Creative in the position to provide their products pre-installed on PCs. In terms of Sound capabilities on PC the most interesting change came in the mid to late 90’s, where Sound card circuitry started to be integrated onto the system motherboard. Discrete sound cards were still better in terms of capabilities, but the built-in sound card included on most systems- even up to today- provides pretty much any sort of Sound capability a typical user may want to use.
In the late 1990’s and early to mid 2000’s, however, Sound Cards did provide features atop what you could find on-board on motherboards. Fundamentally, such sound cards had one of a few distinct markets/purposes:
Games benefited from features such as 3-D Positional audio, hardware streams and mixing, and features such as on-board Sound RAM, used to store audio samples for playback either directly or as part of a Wavetable synthesizer for music.
Professional sound creation and mixing is a different beast entirely. These Cards focused on high-quality components used to provide a high Signal to Noise Ratio at a very high effective sample rate, typically providing strong hardware support to speed up processes involving sound processing and reproduction. These sound cards also have connectivity that allows the use of Professional Audio devices, or include high-grade headphone drivers that support high-impedance headphones.
- Software Emulation
Though motherboard audio is fairly sophisticated today, back in the day many motherboards either had fairly basic Sound Card’s integrated into the motherboard or lacked one altogether. Some “value” sound cards fill this gap by providing many of the features of Professional Audio cards, and, more often, Gaming cards, primarily via Software drivers that emulate those features that are typically provided via Hardware capabilities on the card, and use the provided card to effectively just provide a place for the audio data to go.
Windows Vista turned the world of Hardware-based Audio processing a bit of a curve ball; Windows Vista introduced a User-mode sound mixer built into the OS known as “WASAPI”, or the Windows Audio Service API. The claim is that this redesign took place because a large portion of STOP Errors on XP and earlier were tracable to Sound Card Drivers, which were, like other drivers, running in Kernel Mode. This redesign effectively created a new Audio Stack. Unfortunately, this relegated Sound cards and audio devices to merely “endpoints”; all processing was effectively done by the built-in Audio stack, with the Sound card driver basically allowing WASAPI to send the results to it. What this means is that many features such as EAX are no longer possible to implement via hardware support on Vista or Later. However, these capabilities are available via the use of emulation software.
Therefore hardware advantages for Sound cards for a large portion of users dwindled; even the “Gaming” Sound cards on the market today do very little to actually improve the sound for games or provide game-related features via the hardware.
Professional Audio, however, still has some hardware capabilities. This is because like any hardware device, drivers can do what they want; the reason WASAPI throws a monkey wrench in the works is that it effectively prevents many features from being processed by the hardware, instead, Windows-based sound capabilities need to be provided a certain way, and without kernel-mode involved anywhere in the stack, hardware cannot be invoked. Professional Audio systems, however, typically have their own particular APIs and interfaces, and these have continued to stick around, so hardware capabilities can be exploited fully via hardware interfaces like ASIO.
The Software emulation market is gone- All Motherboards in production today contain Audio capabilities.