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PC Card devices

6.9 Sound
There are two distinct types of PC sound output hardware: 
  • The basic PC speaker.
  • A sound card, such as SoundBlaster.
These are achieved in different ways. The most basic possible ‘PC beep is actually passed over to the host in software, so this needs no additional hardware.
(although if extra shells are loaded in DOS you will not hear it).

Second processor cards

For second processor cards the best results are obtained from the Minnie 16-bit audio card by ESP, and adding the SoundBlaster Emulation software. This presents complete SoundBlaster hardware to the PC so that all Windows and much DOS software can be expected to work in 8 or 16 bits. The hardware is £60 plus VAT: software prices are not currently available – contact Aleph One. 
  • The 16-bit hardware is built into all Risc PC 700 series models.
  • Alternatively, you can fit a parallel port sound adapter.

PC speaker sound – expansion cards

The Aleph One PC cards (except for the Mark I second processor card) generate sound from the on-board PC motherboard chip in the same way as a normal PC does. In order to hear this sound through the host computer’s loudspeaker you must link the two sound systems together using a cable. We can supply you with a suitable cable for £5 plus VAT. Details of how to construct and connect a cable are given in Appendix B. 

To play .WAV files under Windows you will need the SPEAKER.DRV speaker driver from Microsoft. This is now included in this release as a DOS self-extracting archive in the file SPEAK/EXE. Copy this to a DOS floppy disc or a hard disc directory and run it to extract the files. Then read the text files for details of installing the driver. This file is not included with Mark I second processor cards as there is no speaker output. 
 

SoundBlaster sound on expansion cards

To get SoundBlaster sound from an expansion card you will need to fit a parallel port sound adaptor. There are several available. 

The Audio-port by Media Vision Inc. The output is 8-bit mono 2-22kHz, so the sound quality is not particularly high, but sufficient for many applications. It has an internal speaker and a 3.5mm jack socket, a microphone  socket for digitising sound and a Windows 3.1 device driver which gives SoundBlaster, Adlib and ThunderBoard compatibility under Windows in Enhanced mode. It supports DOS applications running under Windows, but not DOS applications on their  own. It can be obtained from companies supplying the PC market, at about £60 plus VAT. 

The Logitech AudioMan is a similar 8-bit device with a built in microphone. 

>This has instructions tailored for use with the Risc PC. It has a built-in unidirectional microphone, and records at 11Khz. It is an 8-bit mono device, and plays at 22KHz. Drivers for playing .WAV files under Windows are supplied. There is no DOS support. It costs £85. Desktop Laminations: PO Box 332 BRISTOL, BS99 7XL (0117 979 9979). 

The Port.able Sound Plus from Digispeech Inc. supports 8 or 16 bits per channel and filetypes such as DVI(IMA), ADPCM, OKI ADPCM and SoundBlaster ADPCM. It can generate simultaneous synthesised music and digitised audio playback with multiple voices. Sockets are provided for stereo audio output to headphones (3.5 mm), audio input from CD-ROM, and a (supplied) mono loudspeaker plus microphone unit. DOS and Windows device drivers are included. It can be obtained from, for example,  Innovative Communications Ltd,  Kinetic Business Centre,  Theobald Street  BOREHAMWOOD WD6  4SE.  Tel 0181 953 0948  at about £120 plus VAT.

Aleph One Ltd. 58-60

 
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