Bulletin Type: HARDWARE Number: ECR3
Date Posted: 12/12/2003
Product Name: eClipseReader / Screen Readers
Version: V1.2 / All
Enhancing PC sound card performance with WDM sound card drivers, and sound card or operating system upgrades:
In the realm of PC Audio technology there are two styles of sound cards
Multi-Channel sound processing is, basically, when a software application or the PC operator attempts to play multiple streams of audio on the PC’s sound card at the same time. An example of this scenario is using a screen reader such as JAWS or WindowEyes with other audio applications such as eClipseReader or Windows MediaPlayer.
A potential adverse effect of single channel sound cards:
Multiple concurrent audio streams on a single channel sound card may cause intermittent sound chop, sound silencing or software application lock-up. This problem can surface during the use of eClipseReader, Screen Readers, music software, etcetera.
Note: This issue can exist in Win 98 or ME operating systems, when using a single channel sound card. Newer operating systems (i.e. Windows 2000 and Windows XP) render the sound card technology, of no concern. These operating systems emulate multi-channel sound technology by mixing audio streams regardless of the style of sound card being used.
A simple test may be performed with eClipseReader to help determine if you are using a single channel sound card.
1. Launch eClipseReader.
2. Open one of the user manuals found in the eClipseReader help menu.
3. Press F2 for book information while the user manual is playing audio.
If you can hear the book information voiced with SAPI speech you are probably operating in a multi-channel sound environment. If you do not hear SAPI speech you are most likely using a single channel sound card.
Enhancing your sound cards performance:
Here are three, suggestions on how to enhance your PC's sound card performance:
Various sound card developers have written updated WDM drivers for their single channel sound cards for operation with Win 98 and ME. These drivers can be found in various places on the Internet or can be obtained from the sound card manufacturer. You can identify these enhanced drivers by the label WDM embedded in the driver name or driver description.
In order to locate the appropriate sound card driver update, you will need to know the sound card type installed on you PC. The following steps will guide you through this identification process:
You may locate WDM sound drivers from several web locations:
Or, using one of the web search engines such as: Google, Yahoo, lycos, etc. Enter your sound card driver name within double quotes followed by a space and “WDM”. The search results should provide various sites containing your driver in the WDM style.
Driver installation procedures are a case-by-case issue. Thoroughly read all installation instructions available from the driver provider.
Some recommended sound cards are –
The audio processing scheme of these newer operating systems will emulate multi-channel audio mixing and processing.