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 1125 W.
TABLE OF CONTENTS INTRODUCTION..........................................................................1 ABOUT DIGITAL AUDIO ..............................................................1 MINIMUM HARDWARE RECOMMENDED..................................6 ADAPTER INSTALLATION ..........................................................6 JUMPER SETTINGS ........................................................6 I/O ADDRESSES AND INTERRUPTS ............................7 SX-12a, SX-20...............................
FIGURES Figure 1: Analog-to-Digital Conversion ........................................3 Figure 2: Digital-to-Analog Conversion ........................................5 Figure 3: SX-12a, SX-20 Connector Locations............................8 Figure 4: SX-7 Connector Locations...........................................8 Figure 5: SX-9 and 11 Connector Locations...............................10 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.
In essence, digital audio is a technological process whereby an analog audio signal (produced when sound waves in the air excite a microphone) is first converted into a continuous stream of numbers (or digits). Once in digital form, the signal is extremely immune to degradation caused by system noise or defects in the storage or transmission medium (unlike previous analog systems).
Figure 1: Analog-to-Digital Conversion To visualize the analog-to-digital conversion process, refer to Figure 1. At the top is one cycle of an analog input signal wave. We've used a simple sine wave to make visualization easier. In this example, the signal has a peak-to-peak amplitude of 20 units, measured by the scale on the left. The sampling frequency is many times higher than the signal being sampled and is shown along the bottom of Figure 1.
In digital-to-analog conversion, the PCM bitstream is converted at the sampling frequency to a continuously changing series of quantization levels which are individual "steps" of discrete voltage equal to the quantization levels in the analog-to-digital process. The shape of this continuously changing stream of quantization levels approximates the shape of the original wave. This is shown in the top half of Figure 2.
Figure 2: Digital-to-Analog Conversion 5
MINIMUM HARDWARE RECOMMENDED ?16 MHz 386-SX or compatible ?28 mSec average access hard disk ?1:1 Interleave hard disk controller ?Mouse ?VGA 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.
I/O ADDRESSES AND INTERRUPTS The valid I/O addresses for the SX7, SX9, SX11, SX-12a, SX20, SX22, SX23e and SX26 are: 180h, 22h, 280h, 300h, 320h and 380h The valid interrupts are: 2, 3, 4, 5, 10, 11 and 12 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.
RIGHT LINE IN LEFT LINE IN HEADPHONE OUTPUT * RIGHT LINE OUTPUT LEFT LINE OUTPUT SX-12a/SX-20 * Stereo Headphones Figure 3: SX-12a, SX-20 Connector Locations LEFT 1 RIGHT GND 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 nc Right Out Left Out nc nc Right Out + Left Out + Figure 4: SX-7 Connector Locations 8
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 Balanced Analog Header SP-100 Header ???????????????????? ???????????????????? DB-9 Balanced Out SX-9/SX-11 SP-100 apt-X adapter Stereo Mini Headphones Unbalanced Right Unbalanced Left AES/EBU, S/PDIF Digital Out Pin 1 2 3 4 5 6 7 8 9 Balanced Analog I /O Connector 5 4 3 2 1 DB-9 Female 9 8 7 pin Mini DIN Female 7 6 5 3 4 2 7 6 Pin 1 2 3 4 5 6 7 1 Assignment Gnd nc nc Right Out Left Out nc nc Right Out + Left Out + Assignment Ground nc Out - AES/EBU+ or S/PDIF+ nc
SX-22, SX-23e, SX-26 There are 5 external connectors located on the SX-22 audio board's metal mounting bracket. There are 7 external connectors on the SX-23e/SX-26. See Figure 6, 7 & 8 for more information on the SX-22/SX-23e/SX-26 connectors. Audio Input: Line: SX-22: Balanced - Nine pin D connector (-10dBu, +4dBu and +16dBu - software selectable) with an impedance of 20k ohms. 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.
SX-23e/SX-26: Balanced - Nine pin D connector 0 to +26dBu (digital clipping) - software selectable with 1dBu resolution, with an impedance of 20k ohms Unbalanced - 1/8” stereo mini jack 2VRMS/+6dBV max (digital clipping), with an impedance of 20k ohms and a load impedance of 10k ohms AES/EBU Digital (SX-22, SX-23e & SX-26): 7 pin Mini DIN jack.
AES/EBU Digital (SX-22, SX-23e & SX-26): 7 pin Mini DIN jack.
Balanced Analog I /O Connector 5 4 Pin 1 2 3 4 5 6 7 8 9 3 2 1 DB-9 Female 9 8 7 6 Balanced In - XLR male shell, female pins GND - 2 1 Assignment Ground Right In Left InRight Out Left Out Right In + Left In + Right Out + Left Out + 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 Balanced Analog Header 2 4 6 8 10 12 14 16
7 pin Mini DIN Female 7 6 5 3 4 2 1 Digital I/O header - JP7 5 ? ? 2 ? ? 4 ? ? 6 7 ? ? 8 (nc) 1 3 Pin 1 2 3 4 5 6 7 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 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 3 2 7 6 5 4 5 2 1 3
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.
Disk 2. The "DOS DRIVERS" disk contains DOS drivers and applications: ? SX25.EXE - DOS V3.3 TSR driver for the SX7, SX9, SX11 SX-12a, SX20, SX22, SX23e and SX26 ? Z1.EXE - DOS V3.3 TSR driver for the Z1, Z1e, SX3, SX33, SX33e ? SX5E.EXE - DOS V3.3 TSR driver for the SX5e ? ADG.EXE - Digital audio player/recorder ? README.TXT (optional) - Additional information WINDOWS DRIVER INSTALLATION 1. Insert the DRIVERS disk into your floppy drive (assumed to be A:) 2. Start Windows 3.
2. Select "Antex Audio Driver for Windows" from the list of installed drivers. Click on Setup. 3. To set adapter type: "Antex Audio Driver Setup" displays the adapter types assigned to adapters 1-4. Change the type by using the drop down menus for each adapter. Information about the number of devices, I/O address, and interrupt number are displayed to the right of each adapter. 4. To set the number of devices, I/O address, or interrupt number: Select Advanced in "Antex Audio Driver Setup".
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 uncompressed. Bit PCM8 - 8 Bit uncompressed. Pulse Pulse Code Modulation, Code Modulation, PCMU8 - 8 Bit Pulse Code Modulation, uncompressed. This format is compatible with Microsoft 8 Bit WAV format.
ADPCM1 - Series 1 compatible Adaptive Differential Pulse Code Modulation compression. ADPCME - Enhanced Adaptive Differential Pulse Code Modulation compression, DVI compatible. CDIB - Compact Disk Interactive compression, CD-ROM XA compatible. level B CDIC - Compact Disk Interactive compression, CD-ROM XA compatible. level C 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.
HEADERLESS - Raw digital audio data without header information. A-SampleRate Allows you to change the sample rate. Enter the desired rate in Hz.(ex 44.1 kHz=44100 Hz) Rec Vol dB Left: <> Right: < > To adjust the recording 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.
S-Start Starts playing or recording. You must select SetPlay or Monitor (Set Record) prior to executing this command. D-Append Allows you to append new recorded material onto the end of an existing file. P - Play Play a file. R - Record Record a file. M - Monitor Monitor the record channel (equivalent to Set Record command). E - SetPlay Queues a file for playing. Press Start to begin playing Center of Screen - Mixer Controls the connections between source and destination lines.
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.
Figure 11: Message Box reporting an unavailable compression format or an invalid sample rate. Compression: This list box selects specific compression formats for recording, and displays the compressed format of the file currently playing. Each Audio Adapter has specific compression formats that it supports. If the compression format selected cannot be used on the Audio Adapter that you have, a message box similar to Figure 11 will appear.
Figure 12: File Open dialog box. File: This button allows for selection of a specific file to be used for recording or playback. Once this button has been pressed the dialog box in Figure 12 will appear. Play/Stop: Once a file has been selected, pressing the play button will start the playback. During playback, this button changes to "Stop". If a file has not been selected the "Open" dialog box appears and allows selection of a specific file to playback.
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 Figure 13: Antex Mixer 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. Features of the Antex Mixer include: SLIDE CONTROLS for adjusting input or output volume levels on all active components and the master volume control.
MIXER BUSES Each mixer input may be routed to either the record or play bus by toggling the bus button directly above each pair of input sliders. RECORD MODE The record bus is a composite mix of all audio inputs with their REC buttons pressed. This mix is routed to the A/D converter and digitized for recording to hard disk. You can then minimize the ANTEX Mixer and use the Antex Demo, Microsoft Sound Recorder, etc. to record. Note: You will not hear any audio until the recording has started.
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.
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