SX-7 SX-9 SX-11 SX-12a SX-20 SX-22 SX-23e SX-26 Digital Audio Adapter User's Manual For DOS and Windows January 25, 1996 ANTEX ELECTRONICS CORPORATION 16100 SOUTH FIGUEROA STREET GARDENA, CALIFORNIA 90248 9000-2347-7006 1
TABLE OF CONTENTS INTRODUCTION..........................................................................4 ABOUT DIGITAL AUDIO .............................................................4 MINIMUM HARDWARE RECOMMENDED ................................7 ADAPTER INSTALLATION .........................................................7 JUMPER SETTINGS .......................................................7 I/O ADDRESSES AND INTERRUPTS............................7 SX-12a, SX-20 ...................................
FIGURES Figure 1: Analog-to-Digital Conversion........................................5 Figure 2: Digital-to-Analog Conversion........................................6 Figure 3: SX-12a, SX-20 Connector Locations ...........................8 Figure 4: SX-7 Connector Locations ..........................................9 Figure 5: SX-9 and 11 Connector Locations ..............................11 Figure 6: SX-22, 23e and 26 Connector Locations....................
INTRODUCTION The Series 2 Digital Audio Adapters are IBM AT compatible add-on boards which convert high fidelity analog signals to digital data for storage to, and retrieval from, disk. The Series 2 adapters sample two channels of audio from 6.25 kHz to 50kHz with 16 bit resolution. They incorporate Sigma Delta technology with 64 times oversampling, providing superior fidelity at greater than 90 dB signal-to-noise ratio.
The number of these bits generated each second is a function of sampling rate. At a relatively low sampling rate of 8 kHz (suitable for voice) far fewer code bits are produced each second than, for example, at the 44.1 kHz sampling rate used for commercial compact disks. For a two-channel stereo signal at a 44.1 kHz sampling rate, some 1.4 million bits are generated each second.
of Figure 2. This signal is then passed through a low-pass filter, which removes the digital "switching noise." The end result, shown in the bottom half of Figure 2 is an analog output signal whose waveshape is a very close approximation of the original analog input signal. The foregoing is a very brief and, of necessity, oversimplified explanation of how digital audio works. For the interested reader, the book Principles of Digital Audio by Ken C. Pohlmann, copyright 1985 by Howard W.
MINIMUM HARDWARE RECOMMENDED Ÿ16 MHz 386-SX or compatible Ÿ28 mSec average access hard disk Ÿ1:1 Interleave hard disk controller ŸMouse ŸVGA display ADAPTER INSTALLATION Make sure the main power to your computer is OFF. You will need a full-size, 16 bit/AT slot. If you are unfamiliar with the internal design of your computer see its "Guide to Operations" manual for step by step installation procedures. Read JUMPER SETTINGS and for information about configuring the adapter before plugging it into the slot.
SX-12a, SX-20 There are 5 external connections located on the front surface of the audio board's metal bracket (Fig. 3). Audio Input: Line: RCA jacks, 2VRMS/+6dBV max (digital clipping), with an impedance pf 20 k ohms Audio Output: Headphone: Line: 1/4" stereo phone jack, 0.5 VRMS into 8 ohms RCA jacks, 2VRMS/+6dBV max (digital clipping), with an impedance of 470 ohms and a load impedance of >10k ohms SX-7 There are four external connectors located on the SX-7 audio board's metal mounting bracket.
LEFT 1 RIGHT G ND JP1 DB-9 Balanced Out SX-7 Headphones Unbalanced Right Unbalanced Left Balanced Analog I /O Connector 5 4 3 2 1 DB-9 Female 9 8 7 6 Pin 1 2 3 4 5 6 7 8 9 Assignment Gnd nc Right Out Left Out nc nc Right Out + Left Out + Figure 4: SX-7 Connector Locations 9
Audio Output: Line: Unbalanced - RCA jacks, 2VRMS/+6dBV max (digital clipping), with an impedance of 470 ohms and a load impedance of > 10 k ohms Balanced - Nine pin D connector, -16 dBm maximum, with an impedance of 47 ohms and a load impedance of 600 ohms Headphone: 1/4" Stereo Phone Jack, 0.5 VRMS into eight ohms SX-9, SX-11 There are 5 connectors located on the SX-9/SX-11 audio board's metal mounting bracket. See Figure 5, 7 & 8. for more information on the SX-9/SX-11 connectors.
Adapter # Jumper Block B ala nced Analog Header SP-100 Header nnnnnnnnnnnnnnnnnnnn nnnnnnnnnnnnnnnnnnnn SX-9/SX-11 SP-100 apt-X adapter Stereo Mini Headphones Unbalanced Right Unbalanced Left AES/EBU, S/PDIF Digital Out 7 pin Mini DIN Female 7 6 5 3 4 2 DB-9 Balanced Out 1 Pin 1 2 3 4 5 6 7 Assignment Ground nc Out - AES/EBU+ or S/PDIF+ nc Out - AES/EBU - or S/PDIFnc AES/SPDIF sense - This line should be connected to Ground for AES/EBU operation and left floating for S/PDIF Figure 5: SX-9 and
The SX-22 balanced analog I/O levels are specified in dBu, where 0 dBu is 0.775 Vrms or 2.19Vpp for a sinewave. If an I/O is connected as unbalanced then the level is 1/2 the balanced I/O. The adjustable level is referred to as Trim. The following Trim settings are available on the SX-22. VdBu VRMS VPP VRMS-if connected as unbalanced -10 0.245 0.693 0.12 +4 1.23 3.47 0.6 +16 4.89 13.8 2.
Headphone (SX-22, SX-23e & SX-26): 1/4" stereo phone jack, 0.5 VRMS into 600 ohms or greater. AES/EBU Digital (SX-22, SX-23e & SX-26): 7 pin Mini DIN jack.
Balanced In - XLR male shell, female pins GND - 2 1 Left + 3 - 2 Unbalanced In - Female RCA 1 Right 5 4 3 2 1 Left + 3 9 8 7 6 Right 1 5 4 3 2 1 - 2 Left 9 8 7 6 + 3 1 Left - 2 Right Right + 3 Balanced Out - XLR female shell, male pins SX22 Balanced I/O to XLR Unbalanced Out - Female RCA SX22 Unbalanced I/O to RCA Balanced Analog Header 2 4 6 8 10 12 14 16 n n n n n n n n n n n n n n n n 1 3 5 7 9 11 13 15 Pin 1 3 5 7 9 11 13 15 Assignment Right In + Right In Left In + Left In
Pin 1 2 3 4 5 6 7 7 pin Mini DIN Female 7 6 5 3 4 2 1 Assignment Ground In - AES/EBU Out - AES/EBU+ or S/PDIF+ In - AES/EBU + Out - AES/EBU - or S/PDIFIn - S/PDIF+ AES/SPDIF sense - This line should be connected to Ground for AES/EBU operation and left floating for S/PDIF Digital I/O header - JP7 1 3 5 7 n n n n n n n n 2 4 6 8 (nc) SX22 S/PDIF cable wiring diagram SX22 AES/EBU cable wiring diagram AES/EBU Output XLR Male pins, Female shell S/PDIF In 2 1 7 6 2 1 3 3 4 3 2 5 7 6 5
DRIVER INSTALLATION DISKS Disk 1. The "WINDOWS DRIVERS" disk contains Windows drivers and applications (Note: The DOS 3.2/Windows 2.0 drivers continue to come on a single disk): · ANTEXWAV.DRV - Windows Wave Driver for SX3, SX5e, SX7, SX9, SX11, SX12a, SX20, SX22, SX23e, SX26, SX33, SX33e, Z1, Z1e · SAPIZ1.DRV - OPL3 FM Synthesizer for Z1 and Z1e · VAPIZ1.DRV - YM3802 MIDI driver for Z1 and Z1e · MIDIMAP.CFG - MidiMapper config file with Z1 and Z1e specific maps · ANTEXMIX.EXE, MMMIXER.
3. In Program Manager, click on File then Run.. 4. Enter A:SETUP in the command line box, then press OK. 5. When the driver installation is complete, Windows should restart automatically. If not, exit then restart Windows manually. WINDOWS DRIVER CONFIGURATION To change the adapter type, I/O address and interrupt settings of the Windows driver: 1. Select Control Panel in the Main group of the Program Manager. Then select Drivers. 2. Select "Antex Audio Driver for Windows" from the list of installed drivers.
DOS DRIVER INSTALLATION 1. Insert the DRIVERS disk into your floppy drive (assumed to be A:) 2. Type A: 3. Type INSTALL driveletter:\path to copy all files from the disk to a subdirectory on your hard disk. ex. INSTALL C:\ANTEX REMEMBER: When the Windows driver installation is complete, Windows should restart automatically. If not, exit then restart Windows manually, or your changes will not be implemented.
USING DOS DEMONSTRATION SOFTWARE On the enclosed disk is the demonstration software for the SX-7, SX-9, SX-11, SX-12a, SX-20, SX-22, SX-23e and SX-26 boards. Filenames are as follows: Driver Program SX25.EXE DOS Demonstration Program ADG.EXE To run the Demonstration Software: 1. Load the disk files into their own directory on your hard disk using the DOS copy command (all files must be in the same directory). 2. Install your mouse driver 3. Install the driver by running SX25.EXE 4. Run the demo ADG.
Figure 9: DOS Demo Environment KEY COMMANDS: Q-Quit Quits the demo program and returns to DOS. C-Channels Allows choice of channel configuration. MONO-Single channel record/play. STEREO-Dual channel record/play. T-Format The format for encoding or decoding audio data: PCM16 - 16 Bit Pulse Code Modulation, uncompressed. PCM8 - 8 Bit Pulse Code Modulation, uncompressed. PCMU8 - 8 Bit Pulse Code Modulation, uncompressed. This format is compatible with Microsoft 8 Bit WAV format.
CDIB - Compact Disk Interactive level B compression, CD-ROM XA compatible. CDIC - Compact Disk Interactive level C compression, CD-ROM XA compatible. DOLBY - Dolby AC-2 Compression. MPEG - ISO/MPEG-1, Layer I/II. Refer to "ISO/MPEG-1 BITRATES & FORMAT EXTENSIONS " for more information. A-law - CCITT G.711 compression (European). Available on the SX-9, SX-11, SX-23e and SX-26. m-law - CCITT G.711 compression (North American). Available on the SX-9, SX-11, SX23e and SX-26. apt-X - apt-X Compression.
To adjust the playback volume, click the mouse over the < or > symbol on the screen. < lowers the volume from 0 to -30 dB in one dB increments. > raises the volume from -30 to 0 dB in one dB increments. Note: 0 dB = full volume. Record/Play Level dB Bargraph displaying the volume of each channel. S-Stop Stops record or playback. S-Start Starts playing or recording. You must select SetPlay or Monitor (Set Record) prior to executing this command.
PROBLEMS RUNNING THE DEMO Symptom: The screen appears to be frozen. Solutions: 1. Verify that the driver is loaded. 2. Make sure you type the correct I/O and interrupt locations on the command line of ADG. 3. Make sure to use the HEX value for the I/O. 4. Make sure syntax of ADG line is correct. 5. Make sure the I/O and interrupt of the adapter are not conflicting with other system hardware.
USING WINDOWS DEMONSTRATION SOFTWARE Figure 10: The Antex Demo Window. The Antex Demo program allows basic recording and playback of .WAV files in any of the compression formats available on the Antex Audio board you have installed in your system. Sample Rate This list box selects specific sample rates for recording, and displays the sample rate of the file that is currently playing. Not all sample rates are available for each compression format.
Channels: These buttons select mono or stereo recording, and displays the current files number of channels. VU Meters: The VU meters show the relative signal of the current file that is being recorded or played. Wave Device: If your computer has more than one Antex Audio board, this drop down list box will allow selection of the specific board to be used for recording and playback. Figure 12: File Open dialog box.
Record/Stop: Once a file has been selected, pressing the record button will start the recording. During recording, this button changes to "Stop". If a file has not been selected the "Save As" dialog box appears and allows selection of a specific file to record into. Volume: These controls allow changing the volume of the playback only. Customer support is available from Antex @ 1-800-338-4231.
ANTEX MIXER The ANTEX Mixer allows you to control the volume of the inputs and outputs on the ANTEX digital audio cards. The Mixer is also the way you route audio sources to either the record bus, for recording to hard disk, or to the play bus, which diverts signals to the line outputs. Figure 13: Antex Mixer Features of the Antex Mixer include: SLIDE CONTROLS for adjusting input or output volume levels on all active components and the master volume control.
PLAY MODE (Feedthrough) The play bus is a composite mix of all audio inputs with their PLAY buttons pressed. This mix is routed to the output jacks. Note: You must toggle the button to REC if you want to record audio to the hard disk. MIXER DEVICES LINE IN jack. WAVE Digital audio playback. Note: This device is playback only, so its Mixer mode is always PLAY. REC IN Record volume control. This slider is a master volume control for all inputs assigned to the record bus. MASTER Play volume control.
UTILIZING DIGITAL AUDIO COMPRESSION UNDER WINDOWS At this point in time Microsoft is in the early stages of supporting various compression formats for waveform audio under Windows. An update to the multimedia standards was released that defines the methods of passing data about compressed files as well as a preliminary list of recognized compression formats.
Audio Adapter Compression Capabilities The Antex Series 2 and Series 3 product line contains audio adapters with a range of signal processing capability. The following table itemizes each product's record and playback functionality with respect to compression format.
ISO/MPEG-1 BITRATES & FORMAT EXTENSIONS ISO/MPEG supports several compression rates and encodes flags that describe the audio data. The flags and other options are selected by typing MPEG with[extensions] switches in the Format text box of the DOS demo.
In the Antex driver the bitrate is specified on a per-channel basis. Therefore, requesting 64 kbits/s and stereo will result in a 128 kbits/s compressed MPEG stream. Supported bitrates (per channel) and compression ratios are as follows: Layer I 32 Khz 44.1 Khz 48 Khz Bitrate (kbits/s) Compression ratio Bitrate (kbits/s) Compression ratio Bitrate (kbits/s) Compression ratio 32 64 96 16 8.0 5.3 32 64 96 128 22.1 11.0 7.4 5.5 32 64 96 128 160 24.0 12.0 8.0 6.0 4.8 Layer II 32 Khz 44.