Antex electronic SX-36 manuale d’uso

SX-5e SX-6 SX-34 SX-36 Digital Audio Adapter User's Manual September 17, 1999 Rev. E A NT EX ELE CTRON ICS COR PORA TION 1125 W. 190 th STREET GA RDENA, CA LIFORNI A 90248 info@antex.com www.a n te x .c o m Toll Free: 1-800-338- 4231 Fax: 310-532-8509 9000-2351-7006[...]

Declaration of Conformity Standards to which Conformity is Declared: EN55022 (Class A) 1994, EN 50082-1 1992 This equipm ent has been v erified to comply with the limits for a class A computing device, pursuant to FCC R ules. In order to m aintain compliance with FCC reg ulations, shielded cables must be used with this equipm ent. Operation with no[...]

TA BLE OF CONTENTS INTRODUCTION ...................................................................... 1 CAR D INSTAL LATION ............................................................. 1 JUM PER S ETTINGS & C ONNEC T IONS ...................... 2 I/O ADDRESSES AND INTERRUPTS .......................... 3 M AKING CON NECTIONS TO THE CA RD .....[...]

SX-34 M IXER A ND BLOC K DIAGR AM ......................... 34 SX-6 M IXER AN D BLOC K DIAGRA M ........................... 36 SX-5e M IXER A ND BLOC K DIAGR AM ......................... 39 ANTE X METE R ........................................................................ 42 TROUB LESHOOTIN G ....................................................[...]

FIGURES Figure 1. SX-5e,6,3 4,35 & SX-36 Jumper Setti ngs ................... 2 Figure 2. SX-35/36 Connecti ons .............................................. 5 Figure 3. SX-34 Connecti ons ................................................... 8 Figure 4. SX-6 Connecti ons..................................................... 11 Figu re 5. Antex D[...]

1 INTRODUCTION The Antex SX-5e, SX-6, SX-34 and SX- 36 fam ily of cards ar e ISA bus audio “add-in” car ds for the PC. They all incorporate DSP’s (Digit al Signal Processors ), which allow the cards to do a variety of audio form ats. (MPEG, PCM16, MSADPCM, etc.) All cards are dual device, which means they can oper ate on 2 hard dr ive files a[...]

2 Set the board num ber with jumpers as shown below. If only one board is being used, leave the jumpers off (s ets to board num ber one). W hen using mor e than one card in a computer, each boar d must be given a diff erent num ber by setting the j umpers dif fer - ently on each card. Any model Antex Card may be used with any other model Antex Card[...]

3 I/O A DDRESSES A ND INTERRUPTS SX-5e, 6, 34, 35 & 36 I/O addresses and interrupts are sof tware selectable. The val id I/O addresses are: 180h, 220h, 280h, 300h, 320h and 380h The valid interrupt s are: 2, 3, 4, 5, 10, 11 and 12 Note that interrupt s 3 and 4 are normally used by the computer ’s COM ports and w ill not be available. The inte[...]

4 balanced connections and shielded coax cable for unbalanced connections. See the section “Balanced and Unbalanced Sig - nals”.[...]

5 SX-35/36 CO NNECTOR DESCRI PTIO N JP1 SX-35/3 6 JP4 JP7 JP8 JP9 BALANCED IN/O UT JP3 Pin A ssi gnm ent 1G r o u n d 2 Rig h t In - 3L e f t I n - 4R i g h t O u t - 5L e f t O u t - 6 Rig h t In + 7 Left In + 8R i g h t O u t + 9L e f t O u t + DB-9 Fem ale Bala nced Ana log I /O Conn ector 1 2 3 4 5 6 7 8 9 SX-35/36 Balanced I/O to XL R 1 2 3 4 [...]

6 LINE I/0 (JP8) Pin 1 Right Line I nput + Pin 3 Right Line I nput - Pin 5 Left Line I nput + Pin 7 Left Line I nput - Pin 9 Right Line O utput + Pin 11 Right Line O u t put - Pin 13 Left Line O ut put + Pin 15 Left Line O ut put - Pin 2,4,6,8, 10,12,14,16 Ground This connector duplicates the f unction of t he DB9 connector. It might be used w ith [...]

7 A UX IN (JP9) Pin 1 Right Aux Input + Pin 3 Right Aux Input - Pin 5 Left Aux Input + Pin 7 Left Aux Input - Pin 9,11,13,15 No connection Pin 2,4,6,8, 10,12,14,16 Ground The Auxiliary input s are balanced inputs, the same as the Line I n and can be used in the same way; as a record source or analog feed- t hr oug h to the Line O ut . MIC (JP 7) Pi[...]

8 SX-34 CONNECTOR DESCRI PTIO N JP5 LINE IN MIC SX-34 A UX LINE OUT JP6 JP7 JP4 JP1 Figure 3. SX-34 Connect i ons 1. SPx Header - JP1 JP1 is a 40-pin, dual-r ow, 2mm spaced header the provides connections for an SPx module. 2. Output Header - JP5 JP5 is a 5-pin, 0.100" spaced header that pr ovides connec- tions for the lef t and right output s[...]

9 3. A UX Header - JP6 JP6 is a 5-pin, 0.100" spaced header that pr ovides connec- tions for lef t and right auxiliary input signals. T hese are the same connections provided by the AUX jack on the brack et. Signals present at JP6 ar e switched in only w hen ther e is no plug in the AUX jack . 1 5 Ground Left In p ut Ri g ht In p ut Ground Gro[...]

10 5. Mono Header - JP4 JP4 is a 2-pin, 0.100" spaced header that pr ovides a mono in- put connection. T his input is not curr ent ly supported. 1 Ground Mono In p ut 2[...]

11 SX-6 CONNECTOR DESCRI PTIO N JP1 SX-6 JP4 JP2 BALANCED OUT JP3 Pin As signm ent 1 Ground 2n c 3n c 4 Right Out - 5 Left O ut - 6n c 7n c 8 Right Out + 9 Left O ut + DB- 9 Femal e Balanced A nal og I /O C onnect or 1 2 3 4 5 6 7 8 9 SX-6 Balance d I/O to X LR 1 2 3 4 5 6 7 8 9 Rig h t Balanced Out - XLR female shell, male pins 1 1 Left - 2 + 3 - [...]

12 LINE OUT (JP 2) Pin 1,3,5,7 No connection Pin 9 Right Line O ut + Pin 11 Right Line O ut – Pin 13 Left Line O ut + Pin 15 Left Line O ut – Pin 2,4,6,8, 10,12,14,16 Ground This connector duplicates the f unction of t he DB9 connector. It might be used w ith a custom “I ndustrial Rack Mount PC” with a special cable harness that br oug ht t[...]

13 SX-5e CONNECTOR DESCRI PTIO N The SX-5e is self -explanatory. T he left and right Line O ut con- nections are RCA jack s on the card br acket, which are labeled. There are no ot her connectors on t he car d. BA LA NCED AND UNBA LA NCED SIGNALS The SX-5e and the SX- 34 have unbalanced signals only. The SX-6 and SX -36 have balanced signals, which[...]

14 Antex cards are “active”; transf ormers ar e not used. Normally, one should not gr ound t he out put of an act ive dr iver. However th e drivers used on the Antex cards are specif ically designed to do this and behave identically to a transf ormer . The main dif ference between grounding or not gr ounding the m inus output is that grounding [...]

15 This is because the input amplifier stages of the car d have been overloaded. Also, recording from a sour ce with too low a signal level, such as plugging a microphone direct ly into a line level in- put, will result in a very noisy recording. Good signal to noise perf ormance can only be achieved by using a record source with suff icient signal[...]

16 externally, there must be 2 cards inst alled in the comput er, so that there is one physical output f or each device. COMPRESSI ON, DATA RA TES, A ND NETWORKS The amount of data (t he size) of a sound f ile is af f ected by several fact ors. The most obvious is the sam ple rate. A f ile recorded at 22.05 KHz will take up half as much disk space [...]

17 a file, but no fading . Some audio editing progr ams do edit MPEG files, but they actually convert the f ile to PCM16 first , and t hen convert it back again af ter editing . This has two pr oblems. First, it is slow , and second, each time the conversion is done, t he sound quality is degr aded. MPEG is only valid for 32, 44. 1 and 48 KHz. MPEG[...]

18 tained for a given output bitrate t heref ore changes with sample rate. In the Antex soft w are the bit rate is specified on a per-c hannel ba- sis. Theref ore, request ing 64 kbits/ s and stereo will result in a 128 kbits/ s compressed MPEG stream. Supported bit rates (per channel) and compression r at ios ar e as f ollows: Layer I 32 KHz 44.1 [...]

19 DRIV ER INST A LLA T ION WINDOWS 95 1. Af t er inst alling the car d, power up the system. 2. Open Contr ol Panel-Add New Hardware applet. 3. Press “Next”. 4. Select “No”. Press “Next”. 5. Select “Sound, video and gam e cont r oller s”. Press “ Next” . 6. Select “Have Disk” . 7. Insert supplied driver disket t e into the [...]

20 5. Sel ect “Driv er” tab. 6. Select antexwav.vxd, click on “Change Dr iver”. 7. Select "Have Disk" 8. Point t o locat ion of driver f iles. Click “OK” . Click “OK” . 9. Select antex.dr v, click on “Change Dr iver”. 10. Select "Have Disk" 11. Point t o locat ion of driver f iles. Click “OK” . Click “O[...]

21 8. Make sure “Search f or a bett er dr iver…” is selected. 9. Select the locat ion of the new driver. 10. Click “ Next”. Click “Next”. Click “Next”. Click “O K”. 11. Point to locat ion of dr iver f iles again. 12. Click “ OK”. Click “Finish”. 13. Click “ Yes” t o r eboot the comput er . WINDO W S NT 1. Aft er in[...]

22 A NT EX A PPL ICA TION S OFTWA RE INSTA LL A TION The Antex Demo, Mixer, and Meter progr am s ar e on a separ at e floppy disk. T he same disk is used f or W indows 95/98 and NT. The sof tware installs in the usual manner . 1. Insert t he disk into the f loppy drive. 2. From the “ Star t” menu, select “ Run”. 3. On the comm and line, typ[...]

23 USING W I NDO WS DEMO NSTRAT IO N SOFTWA RE Figure 5. A nt ex Demo Program The Antex Demo prog ram allows basic recording and playback of .W AV files in any of the compression f orm ats available on the Antex audio board you have installed in your system. Sample Rate This list box selects specif ic sample rat es f or recor ding, and displays the[...]

24 Compression: This list box selects specific compression f ormats f or re- cording, and displays the compressed f orm at of t he file currently playing. Note that the Sample Rate and Com - pression for r ecording can only be changed when the card is in “Stop” mode. If the card is in “Paused Record”, or is recording, t he Sample Rate or Co[...]

25 Channels: These butt ons select mono or ster eo recording , and dis- play the number of channels of the cur r ent file. VU Mete rs: The VU meters show t he relative signal level of the current file t hat is being recorded or played. Wa ve De vi ce : If your driver is config ured for dual devices or your com- puter has mor e than one Antex audio [...]

26 File: This butt on selects a filenam e for recording or playback . Once this button has been pressed the dialog box in Figure 7 will appear. I f you hold down the “Alt ” k ey while clicking on File, the dialog box show n below in Figure 8 will appear. T his will allow you to select aut o-repeat f or play- ing back a file, or recording for a [...]

27 Volume: These contr ols allow changing the volume of the playback only. INSTA LLING AND USING MULTIPLE CA RDS I N A SYST EM W hen using more than one car d in a system, each card m ust have a dif fer ent adapter number. This is set by using the jumper s on top of the car d. The Ant ex Driver must be set up to have a diff erent Address and Int er[...]

28 Simultaneous Record and Playback MPEG MSADPCM PCM 16 SX-34 No 22.05 KHz 48 KHz SX-35 No 22.05 KHz 48 KHz SX-36 32 KHz 32 KHz 48 KHz Dual Device Playback MPEG MSADPCM PCM 16 SX-5e 48 KHz 32 KHz 48 KHz SX-6 48 KHz 32 KHz 48 KHz SX-34 44.1 KHz 32 KHz 48 KHz SX-35 44.1 KHz 32 KHz 48 KHz SX-36 48 KHz 44.1 KHz 48 KHz MIXER AND BLOCK DIA GRAMS The purp[...]

29 and right channels of a st ereo sig nal. Also, only one record device is shown. The small circles with a letter inside correspond be- tween the M ixer Diagram and the Block Diag ram. For example, ref erring to the SX- 36 diagram s, the Line I n On/Of f contr ol, la- beled “G” in t he Mix er Diag ram, is showing that when this control is “O[...]

30 “Radio pushbutton” controls G, H, I , and J determ ine the record source. Only one butt on on at a time is allowed. It m ay seem strang e that button J w ill set the recor d source to Line Out . This is done to allow the use of at tenuators C, D, or E t o contr ol the record level. Using Line Ou t as the recor d source will also allow you to[...]

31 down if the output sig nal fr om the Antex card is t oo loud. One ex- ception to setting both sliders at maximum is when playing 2 files simultaneously. In t his case, it may be necessar y to lower the sliders slight ly to prevent clipping f rom occurr ing when peak s of both f iles occur at the same t ime. Note that this is a subject ive concep[...]

32 L K A A B C D E G H I J Figure 9. SX-36 M i xer[...]

33 Figure 10. SX-36 Bl ock Di agram[...]

34 SX-34 MI XER AND BLOCK DIA GRAM The SX-34 diagram s are the same as the SX-36, with the excep- tion that t he SX-34 does not have the Input or O utput T rim Con- trols. C D E G H I K L Figure 11. SX-34 M i xer[...]

35 Figure 12. SX-34 Bl ock Di agram[...]

36 SX-6 MI XER AND BLOCK DIA GRAM Output T rim Contr ol B determines the level of the output signal on Line Out which corresponds to dig ital clipping. If the cont rol is set to +8, the maximum output signal level is +8 dBu. If the cont rol is set to +20, t he maximum output signal level is +20dBu. Note that these signal levels correspond t o balan[...]

37 M L B K Figure 13. SX-6 M i xer[...]

38 Figure 14. SX-6 Bl ock Diagram[...]

39 SX-5e MI XER AND BLOCK DIA GRAM Due to the simplicity of the SX -5e, the Ant ex M ixer does not add control of any features t hat are not accessible t hrough the Ant ex Demo. T he Play 1 and Play 2 Sliders duplicat e t he f unction of the sliders in the Antex Demo pr og ram. K L Figure 15. SX-5e M i xer Play 1 and Play 2 Sliders, K, and L contro[...]

40 and controlling the volume using the m aster volume contr ol on the external amplif ier or mixing board the Ant ex Card is connected to. One exception to sett ing both sliders at maximum is when playing 2 files simultaneously. In this case, it may be necessary to lower the sliders slightly to prevent clipping from occurring when peaks of bot h f[...]

41 Figure 16. SX-5e Bl ock Di agram[...]

42 A N TE X M ETER The fig ure below show s a typical Antex Meter window . T his can be opened by running “met er.exe” or double-click ing on the met er icon. The siz e of the window can be changed by dragging t he side, bottom or cor ner of the window . The meter is similar to t he meter in t he Antex Mix er or Antex Demo, but is much more fle[...]

43 If you rig ht -click or double- click on the m eter window, the f ollowing window will pop-up: Figure 18. A nt ex M et er pul l - dow n menu[...]

44 Clicking on “ O pt ions” will open the following window: Figure 19. A nt ex M et er opt i ons “Visible Lines” allows you to select which devices have VU meter s displayed. “Mode” allow s you to select w het her the meter is peak reading or averaging ( VU). “Peak Hold Level” will keep t he peak level lit f or the time indicat ed. [...]

45 “Meter Update Interval” deter mines how often the m eter prog ram reads the level data f rom t he Antex Card. Note t hat even if the meter is in peak mode, peak s which occur in between the update intervals will be missed. To avoid t his, the update interval should be 5 ms or less. Once the meter is set the way you want, you can save and rec[...]

46 TR OUBLES HOOTIN G I get an error message when tr ying to run the Antex Demo program. 1. Ca rd did not i nstall corre ctly be cause of an I/O or i nterrupt conflict . In W in NT, g o to “St ar t ”, “Set t ings”, “ Cont r o l Panel” , “Multimedia”, “Devices”, “ Audio Devices”, “Audio f or Ant e x Digital Audio Dr iver”[...]

47 Files I record sound “dul l ” . 1. Use a higher sample r ate. Lower sample rat es reduce the high f requency content , m aking r ecordings sound dull. There is a lot of noise or hum, even w hen the Antex Card is idle. 1. Ther e may be a wiring problem. Make sure the shields are grounded, especially with unbalanced connections. Don’t run ca[...]

48 too hot. T o see if t his is the problem, does t he Line Out sound distorted when just listening to the recor d source as a f eed- throug h? Files recorded are of poor qual i t y. 1. Som e for mats, bitr ates, and sample r ates do not sound as good as other s. PCM8 should not be used. It is provided only for backward compatibilit y . Recor d PCM[...]

49 • If using several cards in a system, tr y just playing one f ile on one card. If this solves t he problem, your system may not be f ast enough to handle as m any cards and f iles at once as y ou want. Using compr essed file f ormat s will re- duce the amount of data req uired by each card. TECHNICA L/O RDERING I NFORMAT I ON: If you have any [...]

50 A PPENDIX Connectors for Male Headers For connecting to the auxiliary connectors on t he Antex Card, there are 2 types of connectors to use. One type is the individual crimp type, such as the Molex C-Grid series. For sing le row headers, the par t number would be 50-57-900X, where X is the number of contacts. For dual r ow headers, t he par t nu[...]

51 milliwatt into 600 ohm s, which is .775 volts RMS. dBV uses 1 volt RMS as the refer ence. Digital Clipping Digital clipping is the point where the Analog t o Digit al converter becomes saturat ed. The sig nal is “all ones”. For a 16 bit system, this is a value of +32768 or –32768. Digital clipping sounds nas- tier than analog clipping beca[...]

52 Specificat ions Unless otherwise noted, THD+N and Dynamic Rang e measure- ments are done at 1KHz , A weighting, 48 KHz sample r ate. Max im um input and output levels are f or dig it al f ull scale. A ll Cards ( as appl i cable): Sample rates ............................ 8, 11.025, 16, 22.05, 44.1, 48 KHz Frequency Response .....................[...]

53 SX-34: THD+N ........................................................................... .02% max Dy namic Range ............................................................... 80dB min Lin e Out lev el .................................................................... 1V RM S Line Out load impedance (90Hz to 20KHz, -3dB) .........8 ohms min L[...]

54 SX-5e: THD+N ................................................................................... .02% Dy namic Range ............................................................... 85dB min Lin e Out lev el ..................................................................... 2VRM S Line Out output impedance......................................[...]

55 In essence, dig ital audio is a technological pr ocess whereby an analog audio signal ( produced when sound wav es in the air excite a microphone) is first converted into a continuous str eam of num - bers (or dig its). Once in digit al form , the sig nal is extrem ely im- mune to degradation caused by sy stem noise or def ects in the storag e o[...]

56 Figure 20. A nal og- t o-Digital To visualize the analog-to- digital conversion process, ref er to Figure 20. At the top is one cycle of an analog input signal wav e. W e' ve used a simple sine wav e t o make visualization easier. I n this example, the sig nal has a peak- to-peak am plitude of 20 units, measured by the scale on the lef t. T[...]

57 Digital- to-analog conversion (used in playback) is the exact oppo- site of the analog -to dig ital conversion process and is illustr ated in Figure 21. In digit al-to-analog conv ersion, the PCM bit stream is converted at the sampling freq uency to a continuously changing ser ies of quantization levels which are individual "steps" of [...]

58 The f oregoing is a very brief and, of necessity, oversimplif ied ex- planation of how digital audio works. For t he interested reader, the book Pr inciples of Digital Audio by Ken C. Pohlmann, copy- right 1985 by Howard W . Sams, is hig hly recommended.[...]