The Sound Blaster Pro handles 8-bit samples. In mono mode, audio data may be sampled at rates from 4,000 to 44,100 samples per second. In stereo mode, samples may be handled at the rates of 11,025 and 22,050 samples per second. The SB-16 can sample 8-bit or 16-bit mono or stereo data in the range of 5,000 to 44,100 Hz. Devices in the AD184x family can handle sample rates up to 48,000 Hz.

The Sound Blaster Pro hardware handles 8-bit linear samples in excess-128 format. The Sound Blaster 16 handles that format as well as 16-bit linear samples in two's complement format. The sbpro driver will generate and accept data in these formats if AUDIO_ENCODING_LINEAR is selected in the encoding field of the audio information structure. 16 bit precision is not available on the Sound Blaster Pro. The sbpro driver will also accept and generate mu-law format data (as in the Greek letter mu) if the encoding field is set to AUDIO_ENCODING_ULAW. In this case, driver software performs the translation between linear and mu-law formats. mu-law encoding is designed to provide an improved signal-to-noise ratio at low amplitude levels. To achieve best results when using mu-law encoding, the audio record volume should be set so that typical amplitude levels lie within approximately three-fourths of the full dynamic range. Devices in the AD184x family support both mu-law and A-law in hardware, and the driver allows either of those encodings to be selected.

The Sound Blaster hardware does not support multiple output devices, so the play.port field of the audio information structure only supports AUDIO_HEADPHONE. Output volume is controlled by software. The volume control thumbwheel on the back of the card should be turned all the way up to maximum; otherwise no sound may be audible.

The record.port field of the audio information structure allows selection of which audio source is used for recording, and may be set to one of AUDIO_MICROPHONE, AUDIO_LINE_IN, or AUDIO_CD. These select input from the microphone jack, line-level input jack, or internal CD input, respectively. The microphone input is treated as a mono source by the hardware, although the microphone jack is a stereo jack. If your microphone has a mono plug, you should convert it to a stereo plug using an appropriate adapter. Line and CD are stereo sources. When recording in mono mode, both stereo channels are mixed before recording.

If your card supports Plug and Play, your device resources are configured automatically. Use the following settings for devices that don't support Plug and Play. Defaults settings are shown in italics.

• IRQ Level: 2, 5, 7, 10
• I/O Address: 0x220, 0x240, 0x260, 0x280
• 8-bit DMA Channel: 0, 1, 3
• 16-bit DMA Channel: 5, 6, 7

Settings for the Compaq Deskpro XL and Turtle Beach Tropez Card are provided below. For each device, the sbpro driver automatically chooses an unused DMA channel and IRQ line.

• Compaq Deskpro XL Business Audio With Built-in AD1847 Chip -- I/O Address: 0x530, 0x604, 0xE80, 0xF40 Note – The sbpro support for the AD1848 and compatibles uses one DMA channel for both play and record; simultaneous play/record is not supported.
• Turtle Beach Tropez Card With CS4231 Chip -- I/O Address: 0x530 (The MWSS I/O address on the Turtle Beach Tropez card is 0x530 at power-up. It can only be changed by software after the system is booted, a function that the Solaris operating environment does not perform. Therefore, the Tropez card is only supported at I/O address 0x530).Note – The Tropez card comes with a software utility for selecting the IRQ, DMA, and MWSS compatibility I/O address settings used by the card. However, that utility does not record those parameters in nonvolatile memory, but in a configuration file used by DOS to set the card's configuration at each reboot. This type of configuration file is not used by the Solaris software and does not affect the operation of the card with the Solaris operating environment.

• Any Crystal Semiconductor CS4231-based devices supported by this driver are programmed in AD1848-compatibility mode. This driver does not include support for advanced CS4231 features; in particular, simultaneous play/record.
• The Sound Blaster card cannot share IRQ settings with any other card installed in your system. The most common conflicts occur with the LPT1 parallel port or a network card.
• Some devices can detect that the IRQ is in use by another device in the system. If this occurs, the driver prints an error message:

  sbpro: MWSS_AD184x IRQ 7 is 'in use.'

  To correct this, change the IRQ setting of either the audio device or the conflicting device. (Some devices are not able to detect such a conflict. The driver will try to use the card, but that will likely result in the system hanging when the card is first used. Thus, it is important to check that the IRQ that does not conflict with another device.)

• Although the sbpro driver supports A-law encoding on AD1848 and compatible devices, audiotool does not and produces an error message if you select A-law encoding. Use audioplay(1) to play A-law encoded audio files, or use audioconvert(1) to convert the A-law sample into a format that audiotool will accept, such as 16-bit linear. User-written applications can select A-law format using the sbpro driver on AD1848 and compatible devices.

• Non-Plug and Play Sound Blaster 16, Sound Blaster Vibra 16, and Sound Blaster AWE32 cards are recognized as Sound Blaster 16 cards.
• The ISA version IBM Token Ring and compatible adapters will not work in a system that contains a Sound Blaster card that is configured at the default I/O port address (0x220). If possible, move the Sound Blaster card to port address 0x240; otherwise, remove the Sound Blaster device from the system.