ISP-100 INTEGRATED SIGNAL PROCESSOR Users Manual
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i PROPRIETARY NOTICE The Merlin product information and design disclosed herein were originated by and are the property of Telex Communications, Inc. Telex reserves all patent, proprietary design, manufacturing, reproduction, use and sales rights thereto, and to any article disclosed therein, except to the extent rights are expressly granted to others. PATENT NOTICE This equipment contains and uses a design for which patent applications have been made. Patents Pending.
ii ANY AND ALL IMPLIED WARRANTIES, INCLUDING THE IMPLIED WARRANTY OF MERCHANTABILITY ARE LIMITED TO THE DURATION OF THIS EXPRESS LIMITED WARRANTY. NEITHER TELEX NOR THE DEALER WHO SELLS MERLIN PRODUCTS IS LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND. CUSTOMER SUPPORT Technical questions should be directed to: Customer Service Department Merlin/Telex 9600 Aldrich Avenue South Minneapolis, MN 55420 U.S.A.
iii End-User License Agreement for Telex® Software IMPORTANT – Please read this document carefully before using this product. THIS DOCUMENT STATES THE TERMS AND CONDITIONS UPON WHICH TELEX COMMUNICATIONS, INC. (the “COMPANY”) OFFERS TO LICENSE THE INSTALLED SOFTWARE OR PROGRAM (the “SOFTWARE”) FOR USE WITH THE PRODUCT IN WHICH IT WAS INSTALLED. YOU ARE AGREEING TO BECOME BOUND BY THE TERMS OF THIS AGREEMENT. IF YOU DO NOT AGREE TO THE TERMS OF THIS AGREEMENT, DO NOT USE THIS PRODUCT.
iv Table of Contents INTRODUCTION .................................................................... 1-1 An Overview of the ISP-100 ................................................................................................ About this Manual ................................................................................................................ Customer Support ...............................................................................................................
v Table of Contents LowPass Filter ........................................................................................................... 4-2 HighPass Filter .......................................................................................................... 4-2 AllPass Filter.............................................................................................................. 4-2 LowShelf Filter ............................................................................................
vi Table of Contents INSTALLING VUE-IT ........................................................... 5-1 Minimum System Requirements ......................................................................................... Identifying a Serial Port ....................................................................................................... Loading the Software ..........................................................................................................
vii Table of Contents OpenDevice Status Panel on Error ............................................................................... 7-4 Display QuickMAP Pop-Up names ................................................................................ 7-4 Display Filter Bandwidth in “Q” ...................................................................................... 7-4 System Configurations ........................................................................................................
viii Table of Contents Polarity Control (+/-) ...................................................................................................... 8-3 Mute Control (M) ........................................................................................................... 8-3 Bypass Control (master) ................................................................................................ 8-3 Compressor .............................................................................................
ix Table of Contents Bypass Control (master) .............................................................................................. Filter .................................................................................................................................. Filter Bands ................................................................................................................. LowPass Filters ..........................................................................................
x Table of Contents Familiar Controls ......................................................................................................... Unfamiliar Controls ...................................................................................................... Notes on Operation of the Limiter ................................................................................ Meter ...........................................................................................................................
1-1 INTRODUCTION An Overview of the ISP-100 Thank you for choosing the ISP-100™ for your signal processing needs. The ISP-100 is the first in a line of high quality signal processing products from TELEX Communications, Inc.’s Merlin division. The ISP-100 represents a continued commitment to understanding and meeting our customers needs through the development of innovative and intuitive solutions.
1-2 closures. This interface allows users to change system settings directly and/or scroll through various settings. About this Manual This manual is covers the installation and operation of the ISP-100’s hardware and software. The ISP-100 has been designed to be as user-friendly as possible. However, this manual should be read before attempting to install or operate the ISP-100. Customer Support Be sure to fill out the customer support registration card included in the software envelope.
2-1 SETUP & INSTALLATION Introduction This section details the setup and installation of the MERLIN ISP-100. Information is provided on the following: front and rear panel features, physical requirements, installation of expansion cards, signal connections for audio, data, and control. Unpacking Save the shipping carton in case the ISP-100 needs to be returned for service. The shipping carton is specially designed to protect the ISP-100 while transporting under normal conditions.
2-2 Rear Panel Features (see Figure 2-2) Figure 2-2 ISP-100 rear panel features. 1. AC Power—Connects to mains via an IEC type AC power cord. 2. RS-232 Port—Links the PC to the unit via a RJ-45 connector. 3. External Sync—Precision frequency reference input to the unit. 4. GPI—Provides a General Purpose Interface for the user. The user provides inputs to the system via dry or electronic contact closure inputs.
2-3 Card Installation Procedure Figure 2-3 Battery/module tool. CAUTION: Failure to observe anti-static handling procedures could result in damage to equipment. Figure 2-4 Card being inserted. 1. Ground yourself using a wrist strap and anti-static mat. 2. Turn off the ISP-100. 3. Remove the screws securing the module slot cover. 4. If you are not replacing an existing card please proceed to step 6. 5. Use the battery/module removal tool to remove the existing module.
2-4 Cable Diagrams Analog Audio (MIM-1, MIM-2, MOM-1) Using low-cost connectors can save money in the short term, but failures could cost more. Figure 2-6 Analog inputs. Balanced Input from Balanced Output Connect the positive (+) side of the line to pin 2 of the male 3-pin XLR connector and the negative (-) side of the line to pin 3 of the connector.
2-5 Balanced Output to Unbalanced Input Connect the “hot” wire to pin 2 of the 3-pin female XLR connector and the shield wire to pin 1 of the connector. To avoid a 6 dB drop in level, connect pin 3 to pin 1 of the connector. See Figure 2-7 for more information. Digital Audio (MDM-1 Cards) Use the white block on the I/O module panels to write a reference number or other designator on by using a permanent marker. Then make identical labels for the cables that plug into the module. Figure 2-8 AES/EBU inputs.
2-6 AES/EBU Output Figure 2-10 AES/EBU output. Connect the positive (+) side of the line to pin 2 of the 3-pin female XLR connector and the negative (-) side of the line to pin 3 of the connector. In keeping with standard wiring practices, the shield should be connected at this end; it should not be connected to pin 1 of the male 3-pin XLR connector or ground of the receiving end. The cable used should be 110Ω AES/EBU compliant cable such as MOGAMI 3080. See Figure 2-10 for more information.
2-7 Figure 2-13 RFI choke data. Not using an RFI choke while using the front panel serial port could cause increased interference with other devices and void the FCC compliance. RFI choke such as Steward PN: 28B2025-0A0 should be used at the ISP-100 end of the cable. See Figures 2-13 and 2-16, and Table 2-1 for more information. Rear Panel RS-232 Figure 2-14 RJ-45 to DB-25. Figure 2-15 RJ-45 to DB-9. The serial port selector switch should be set in the up position.
2-8 Table 2-1 RS-232 signal pinouts for RJ-45, DB-9, and DB-25 connectors. Figure 2-16 Connector pinouts. 10 July 1998 The RS-232 standard is very common to computer controlled devices. Table 2-1 and Figure 2-16 can help you decipher the RS-232 interfaces of many devices.
2-9 General Purpose Inputs (GPI) If a permanent contact closure is used, the ISP-100 will remember the QuickSET selected even if the AC power fails. Figure 2-17 GPI connector pinout. Dry (i.e. switch) or electronic (i.e. open collector) contact closure should be sufficient. The closure can be either momentary (10 ms minimum duration) or continuous. Connect the desired input (1-8) through the contact closure to common (9). See Figure 2-17 for more information.
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3-1 TROUBLESHOOTING > > > CAUTION < < < NO USER SERVICEABLE PARTS INSIDE. HAZARDOUS VOLTAGES AND CURRENTS MAY BE ENCOUNTERED WITHIN THE CHASSIS. TO AVOID ELECTRICAL SHOCK DO NOT PERFORM ANY SERVICING OTHER THAN THAT CONTAINED IN THESE OPERATING INSTRUCTIONS. User Modifications User modifications void the warranty. Modifications to Merlin products are not recommended.
3-2 Diagnostics Table 3-1 LED diagnostic messages. The ISP-100 was designed with built-in diagnostics that activate when power is applied to the unit. During the power-up cycle, the ISP-100 performs several self-checks. The ISP-100 also will report problems, as they happen, while the unit is running. The diagnostic messages are communicated through the front panel LEDs. Refer to Table 3-1 for a list of common LED conditions and corresponding diagnostic messages.
3-3 Retrieving Version Numbers Figure 3-1 About VUE-IT dialog Application, OS, and DSP version numbers can be obtained by clicking on the Help menu and then selecting the About entry. See Figure 3-1. If an ISP-100 is not online, only the application version number will be reported. Retrieving Serial Numbers Figure 3-2 Properties dialog. Clicking on the star icon in the Project Manager and then clicking on the Properties button will reveal the ISP-100’s serial number. See Figure 3-2.
3-4 Changing the Fuse The universal switching power supply in the ISP-100 adapts to input voltages from 90 to 264 VAC, 50/60 Hz. To reduce risk of fire, replace only with same type fuse. The fuse holder is located under the security cover on the front panel. WARNING: Disconnect AC power before changing the fuse. Failure to do so could result in a shock hazard. The fuse is a standard 20mm X 5mm European type.
3-5 Saving the ISP-100 configuration data to disk will guard against the loss of data in the event AC power fails before a failed battery has been changed. Caution: Use only the tool attached to the inside of the security cover to change the battery. The tool is black anodized so it will not short out the battery or anything else. DO NOT under any circumstance use pliers to grip the battery. Doing so could cause damage. See Figure 3-3. Replace the battery with a Renata CR2450N battery.
3-6 Technical Support Technical questions should be directed to: Customer Service Department - Merlin Telex Communications, Inc. 9600 Aldrich Avenue South Minneapolis, MN 55420 U.S.A. Telephone: (612) 884-4051 Fax: (612) 884-0043 Helpful Information Be prepared to provide the following information (if possible): 1. 2. 3. 4. 5. 6. 7. 8. A detailed description of the problem. QuickMAP being used. Serial Number(s) Version numbers for application, OS, and DSP software. Front panel LED information.
3-7 Save the box the ISP-100 was shipped in. It makes a convenient way to package a repair unit. Shipping to Manufacturer for Repair or Adjustment All shipments of Merlin products should be made via United Parcel Service or the best available shipper prepaid. The equipment should be shipped in the original packing carton; if that is not available, use any suitable container that is rigid and of adequate size.
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4-1 SPECIFICATIONS Components Compressor Property Bypass Threshold Compression Ratio Attack Time Release Time Detection Window Crest Factor Knee Sidechain Channel Range in/out -60 dB to 0 dB 1.2:1 to 24:1 20 msec to 50 ms 20 msec to 5 sec 20 msec to 5 sec 0.00 to 1.00 hard/soft self, max of both, or sidechain Default out 0 dB 1.2:1 20 msec 5000 ms 50 ms .70 hard depends Fine n/a .5 dB n/a .02 ms 1 ms 1 ms .01 n/a n/a Coarse n/a 3 dB n/a 1 ms 100 ms 100 ms .
4-2 Limiter Property Bypass Threshold Attack Time Release Time Detection Window Crest Factor Knee Sidechain Channel Range in/out -60 dB to 0 dB 20 msec to 50 ms 20 msec to 5 sec 20 msec to 5 sec 0.00 to 1.00 hard/soft self, max of both, or sidechain Default out 0 dB .02 ms 5000 ms 50 ms .70 hard depends Fine n/a .5 dB .02 ms 1 ms 1 ms .01 n/a n/a Coarse n/a 3 dB 1 ms 100 ms 100 ms .05 n/a n/a Range in/out +/+12 dB to -12 dB Default out + 0 dB Fine n/a n/a .
4-3 PEQ Property Center Frequency Boost/Cut Bandwidth Range 20 Hz to 20 kHz +12 dB to -12 dB 0.08 to 3.0 octaves Default 20 0 dB 1.0 Fine 1/12 Oct. .1 dB 1/12 Oct. Coarse 1/3 Oct. 1 dB 1/3 Oct. Range +0 dB to -96 dB +/+0 dB to -96 dB +/- Default 0 dB + 0 dB + Fine .5 dB n/a .
4-4 Gate Linkwitz-Riley 3-way Crossover Notch Filter Parametric Equalizer Filter Peaked HighPass Filter Shelving Filter AP is a trademark of Audio Precision, Inc.
4-5 System Measurements System Frequency Response System Noise Floor System THD+N AP is a trademark of Audio Precision, Inc.
4-6 MIM-1 & MIM-2* Analog Input Modules Power Symbol VA18P VA18M VD5P IA18P IA18M ID5P Description positive analog supply voltage negative analog supply voltage positive digital supply voltage positive analog supply current negative analog supply current positive digital supply current Minimum 17.50 -17.50 4.75 77(43.7) 72(41.6) 113(114) Typical 18.00 -18.00 5.00 81(46.0) 76(43.75) 123(124) Maximum 20.00 -20.00 5.50 85(48.3) 80(46.
4-7 MOM-1 Analog Output Module Power Symbol VA18P VA18M VD5P IA18P IA18M ID5P Description positive analog supply voltage negative analog supply voltage positive digital supply voltage positive analog supply current negative analog supply current positive digital supply current Minimum 17.50 -17.50 4.75 92 47 114 Typical 18.00 -18.00 5.00 96 51 124 Maximum 20.00 -20.00 5.50 100 55 134 Units volts volts volts milliamps milliamps milliamps Minimum Typical 0.003 0.004 0.003 110 -100 20 +0.1, - 0.
4-8 MDM-1 AES/EBU Digital I/O Module Power Symbol VA18P VA18M VD5P IA18P IA18M ID5P Description Pos Analog Supply Voltage Neg Analog Supply Voltage Pos Digital Supply Voltage Pos Analog Supply Current Neg Analog Supply Current Pos Digital Supply Current Minimum 17.50 Maximum 20.00 122 Typical 18.00 Not Used 5.00 9 Not Used 155 168 Units Volts Volts Volts mA mA mA Minimum 32 Typical 48 Maximum >54 Units kHz 0.00002 0.00016 % TBD % 415 pS 90 nS 20 24 +/-0.
4-9 Performance (Sample Rate Converter bypassed) Symbol F s THD+N IMD Description Sample Rate for Digital 19 Input Data Total Harmonic Distortion 20 plus Noise (RELATIVE) 21 Intermodulation Distortion (SMPTE 4:1) Jitter in Output Clock Tolerable Jitter in Input 22 Clock before Loss of Lock Resolution (input) Resolution (output) 23 Frequency Response 24 Dynamic Range 25 Noise Floor 26 MCLK+ WSR+ WST+ SCKR+ SCKT+ Z in Z out Delay through receiver 27 Delay through transmitter 28 Interchannel Phase Deviat
4-10 1 Notes Per Analog Devices AD1890 data sheet, where applicable. 2 With 6.144 MHz MCLK/2 input. 3 20 Hz to 20 kHz, full-scale input, through sample rate converter, to output via passthrough. 4 From input, through sample rate converter, to output via passthrough. 5 When installed in ISP-100. 6 When installed in ISP-100. 7 Input samples longer than 20 bits are truncated to 20 bits. 8 Least four significant bits are zero filled.
5-1 INSTALLING VUE-IT Minimum System Requirements CPU: Pentium® processor. VUE-IT is currently not available for Windows NT. OS: Microsoft® Windows 3.1x, Windows 95, or Windows 98 Memory: 8MB RAM Hard Drive: 5MB of available space (beyond swap file needs) Disk Drive: 3.
5-2 Updating the ISP-100’s Operating System Figure 5-1 OS mismatch dialog. Figure 5-2 OS download request dialog. The updating of the operating system contained in the ISP-100’s flash memory is usually required after loading a new version of VUE-IT on the computer. A dialog box such as those in Figures 5-1 and 5-2 usually indicates this. The procedure is as follows: 1. Make sure both the computer and the ISP-100 are both turned off. 2. Connect the computer to the ISP-100. 3.
5-3 Figure 5-3 Open OS file dialog. 5. Download the OS software file you need via the application when prompted. See Figure 5-3 for more information. The default location for OS files is “c:\program files\vue-it\isp-100”. Figure 5-4 Download progress dialog. 6. The lights will continue to rotate with only brief pauses. You will also see a progress indicator on the PC’s screen similar to the one in Figure 5-4. 7. When the download is complete, the ISP-100 will automatically restart.
5-4 Configuring the Software Turn on the ISP-100. The power switch is located at the far right under the front access panel. This is accomplished by placing the switch in the down position. See Figure 2-1 for the location of the power switch. Check to make sure that the LEDs light in a percentage complete fashion. Launch the VUE-IT application on the PC. Figure 5-6 System configuration dialog. A dialog box similar to the one in the Figure 5-6 should appear.
5-5 Figure 5-8 ISP-100 not detected dialog. If a dialog box like the one in Figure 5-8 appears in place of the one in Figure 5-7, the cable connecting the computer to the ISP-100 should be checked. If no problem is found there, try selecting a different serial port. Figure 5-9 Communications error dialog. If a dialog box similar to the one in the Figure 5-9 appears, then a serial port that does not exist has been selected. Another serial port must be selected.
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6-1 GETTING STARTED Starting VUE-IT Figure 6-1 VUE-IT workspace. When VUE-IT is started, you will see a screen similar to the one in Figure 6-1. The window displayed in Figure 6-1 is the basic environment in which all interactions with VUE-IT take place. There are six key features of this window that users should be aware of: 1. Menu Bar - This is where the user will find features that are either integral to VUE-IT or standard in windows.
6-2 Starting a New Project Figure 6-2 Create new project dialog. To start a new project select New Project from the File menu. A panel similar to the one in Figure 6-2 will appear. You are allowed to select a name of up to eight characters for the project, assign a path for the project to be stored, and create a new subdirectory if needed. You also will need to select the method by which the new project will be created.
6-3 used to create the QuickMAP. The QuickMAPs can be sorted by Name, I/O Configuration, Creation Time, and Modification Time. To sort the QuickMAPs, click on the heading button of the property you wish to sort by (i.e. Name, I/O Configuration, etc.). The first click of the mouse will sort the QuickMAPs in ascending order and the second click will sort them in descending order. If you select the Upload from ISP-100 option there will be a pause while the QuickMAP in the ISP-100 is loaded.
6-4 Archiving Projects To save a project for archival purposes do the following: 1. Exit VUE-IT. 2. Save the project directory and the four files mentioned previously to the archival media (i.e. floppy disk, zip™ disk, tape, CD, etc...). The directory name will usually be the name you assigned the project. Mounting Projects To install a project from an archive do the following: 1. Exit VUE-IT. 2. Create a directory under the C:\PROGRAMS\VUE-IT\ISP-100\PROJECTS\ directory. 3.
7-1 Using VUE-IT VUE-IT has a variety of commands available to the user. These commands are accessible via the menu items along the top of the VUE-IT workspace window. File (see Figure 7-1) Figure 7-1 File menu. New Project - Creates a new project file. Open Project - Loads an existing project. Save - Saves a project. Save as... - Saves an existing project under another name. Activate Project Manager - Opens the project manager window after it has been closed.
7-2 Edit (see Figure 7-2) Figure 7-2 Edit menu. Cut - Removes the selected item(s) and places them on the clipboard. Copy - Places a copy of the selected item(s) on the clipboard. Paste - Inserts item(s) from the clipboard. Tools (see Figure 7-3) Figure 7-3 Tools menu. Refresh Directories - Updates the directory list for QuickMAP and component library files. Scan - Looks to see if an ISP-100 is connected to the computer. Options (see Figure 7-4) Figure 7-4 Options menu.
7-3 Window (see Figure 7-5) Figure 7-5 Windows menu. Cascade - Arranges panels in overlapping layers. Tile - Arranges panels side-by-side. Arrange Icons - Arranges minimized panels side-by-side. Help (see Figure 7-6) Figure 7-6 Help menu. About - Lists the current application software version, OS version, and DSP version if an ISP-100 is connected and online. If an ISP-100 is not online, only the application software version will be reported.
7-4 there is when changing between QuickSETs or using a GPI mute. The total time for ramp-up and ramp-down is twice the time specified. (i.e. If 50 ms of time is specified, the ramp-down will be 50 ms and the ramp-up will be 50 ms. Thus, the total time between the start of the ramp-down to the end of the ramp-up is 100 ms.) Display recently opened files in the File Menu The check box turns on and off the Most Recently Used files (MRU) function.
7-5 QuickMAP Library This is the directory under which QuickMAP templates are stored. To modify the path, click on the Modify... button located to the right of the directory path entry. Company Name This entry is reserved for possible future use in documenting projects. You can enter the company name, but it currently will not be saved in a project. Designer’s Name This entry is reserved for possible future use in documenting projects.
7-6 able to access ISP-100 statistics such as free memory, number of QuickSETs, etc. Properties for the ISP-100 Figure 7-10 ISP-100 properties dialog. Properties for the ISP-100 (see Figure 7-10) reports statistics on the ISP-100. It is accessed by double clicking on the entry next to the star icon (see Figure 7-9), or by clicking on the entry next to the star icon (see Figure 7-9) and then clicking on the Properties button in the Project Manager.
7-7 Project Properties Figure 7-11 Project properties dialog. Project properties (see Figure 7-11) provides the user with information on the name of the project, project location, and notes related to the project. It is accessed by double clicking on the project name entry, or by clicking on the project name entry and then clicking on the Properties button in the Project Manager. QuickMAP Selection A QuickMAP is a signal processing topology used with an ISP-100.
7-8 Configuration, etc.). The first click of the mouse will sort the QuickMAPs in ascending order and the second click will sort them in descending order. See section 6 for the location of the QuickMAP directory. QuickMAP Properties Figure 7-12 QuickMAP properties dialog. QuickMAP Properties (see Figure 7-13) appear by clicking on the QuickMAP entry in the Project Manager and then clicking on the Properties button. From this dialog, you can change the QuickMAP name.
7-9 Clicking on a component (i.e. Cut, Compressor, Limiter, etc.) in the Project Manager (see Figure 7-9) and then clicking on the Properties button displays the properties for the selected component. Component Properties allow the user to name the component and enter notes related to that component. See Figure 7-14. Component Export Figure 7-15 Component export dialog.
7-10 Component Import Figure 7-16 Component import dialog. To import component settings from the Project Manager, click on the desired component entry in the project manager (see Figure 7-9) and then click on the Import button. You will then see a dialog box like the one in Figure 7-16. The Import Component dialog displays currently existing component presets’ filenames in the upper half of the dialog box. These files can be sorted by clicking on the Name, Type, Group, and Mod Time heading buttons.
7-11 The QuickSET Manager (see Figure 7-17) allows the user to develop and manage multiple groups of component settings. The QuickSET Manager is opened when a component is opened. A QuickSET is made up of the settings of all of the components in a QuickMAP. Multiple QuickSETs allow users to change the component settings for a QuickMAP. QuickSETs can be changed without a computer by assiging a QuickSET to a GPI input.
7-12 will appear, and the proper command can be selected from the list by clicking on it. The list displays the following options: Empty - No command assigned to input pin. Mute Combo - The initial contact closure causes the outputs to mute. The subsequent contact closure causes the output to un-mute. Mute Enable - Contact closure causes the outputs to mute. Mute Disable - Contact closure causes the outputs to un-mute.
7-13 QuickMAP A QuickMAP is a signal processing topology used with an ISP-100. The QuickMAP sets the signal paths and processing from input to output. An ISP-100 can hold one QuickMAP at a time. Figure 7-20 QuickMAP panel. Double clicking on the QuickMAP (name) entry or by clicking on the entry and then clicking on the Design button can access a graphical representation of the selected QuickMAP (see Figure 7-20).
7-14 I/O Properties (see Figure 7-21) Figure 7-21 I/O properties dialog. Input The Input Function controls the levels entering the unit. This function can be accessed in any of the following three ways: 1. Clicking on the green input triangles. 2. Right clicking on either the green input or green output triangles and selecting Properties from the pop-up list. 3. Clicking on the I/O Slots entry in the Project Manager and then clicking on the Properties button.
7-15 Output The Output function controls the output levels from the unit. Using the Stereo Control This button controls the tracking of the Gain/Attenuator levels. If the LED is gray, then the two channels do not track each other. If the LED is blue, then the channels will track each other. Clicking on the button will toggle the setting. Mute Control This button determines if the output signal will be muted.
7-16 Status Information Figure 7-22 Digital I/O status panel. Status information can be obtained for card slots 1 and 2 by clicking on the Status button in the desired slot. See Figure 7-22. Sample Rate Converter On indicates that the sample rate conversion option is selected on the card. The card cannot be selected as the clock master if the SRC is turned on. Off indicates that the sample rate conversion option is not selected on the card.
7-17 Device Status Panel Figure 7-23 Device status panel. Clicking on the entry next to the star icon (see Figure 7-9) and then clicking on the Design button in the Project Manager opens the Device Status Panel. See Figure 7-23. The device status panel has five simulated LEDs: Clock Sync (red) The main board cannot lock to specified location or frequency. Digital Data (red) 1. Data validity error. Card position dependent. 2. A non-48 kHz Sample Rate is being used, and no Sample Rate Converter is selected.
7-18 Output Meters Figure 7-24 Output meter panel. The Output Meters (see Figure 7-24) provide monitoring of the outputs of the DSPs before digital-to-analog conversion. To activate the Meters, click on the green output triangles in the QuickMAP, or click on the Meter Bank entry in the Project Manager and then click on the Design button.
8-1 PROCESSING COMPONENTS The components used in the VUE-IT interface have a wide variety of controls for adjusting settings. Each component description begins with a full explanation of the component including all of the parameters that can be adjusted. In some areas the explanations may go into more depth than the average user would need. This was done in order to satisfy the advanced user who feels a need to understand the inner workings of the component.
8-2 Combine Figure 8-1 2-to-1 combine component. The Combine component (see Figure 8-1) adds multiple input signals together and sends the sum to a single output. In QuickMAPs, 2-to-1, 3-to-1, and 4-to-1 combines may exist. The combine’s default attenuation is set so that the combine’s output level is unity.
8-3 Fine (F) or Coarse (C) Control This button determines the increment/decrement associated with the UP/DOWN arrows. Fine produces small steps in value, while Coarse provides large steps in value. Clicking on the button will toggle the setting. Polarity Control (+/-) This button determines the polarity of the signal. A + indicates that the signal will not have it’s phase altered. A - indicates that the signal’s phase will be changed 180°. Clicking on the button will toggle the setting.
8-4 Compressor Figure 8-2 Compressor component. A compressor (see Figure 8-2) is used in situations where the input signal has a greater dynamic range, or ratio of loudest to softest, than is desired in the output signal. Compression is accomplished by preventing the output signal from changing in level as much as the input signal, and can be thought of as a form of automatic gain riding.
8-5 threshold value, no compression takes place and the change in level of the output signal exactly matches the change in level of the input signal. When the input signal level is above the threshold value, compression is used and the change in level of the output signal is less than the change in level of the input signal by the amount dictated by the selected compression ratio. Threshold is adjustable in the range -60 dBFS to 0 dBFS.
8-6 2.5 dB below the input level at the threshold. The divergence continues to increase gradually until approximately 6 dB above the threshold, beyond which the output level rise is dictated solely by the selected compression ratio. There is a smooth, gradual transition from no compression below the threshold to compression above. The sonic differences between the two knee types are often subtle and are very much signal-dependent. Experimentation is recommended.
8-7 Crest Factor Sensitivity A signal’s crest factor is the ratio of a its peak level to its average level. The signal having the lowest possible crest factor is the square wave, whose peak and average levels are equal and whose crest factor is therefore 1.0. The peak level of a pure sinewave tone is 1.414 times its average level; a sinewave therefore has a crest factor of 1.414.
8-8 input signal was going to be, then the Crest Factor Sensitivity control would ideally be set to: 1 Crest Factor of Input Signal Since this quantity is not generally known, it is best to experiment until satisfactory results are obtained. Metering The compressor meter shows the attenuation applied to the signal passing through the compressor at any given moment in time. When the signal is being compressed the meter indicates negative values (gain less than 1.0).
8-9 not its compressor control settings. If multiple compressors utilize the same channel as their sidechain sources, then all controls on all compressors must still be configured. Meter The meter located at the left of the component indicates the amount of attenuation taking place in dB. Threshold The Threshold can be adjusted three ways: Using the Slider Click on the indicator on the slider and while continuing to hold down the mouse button, move the mouse up and down.
8-10 Using the UP/DOWN Arrows To increase the level, click on the up arrow. To decrease the level attenuation, click on the down arrow. The amount of increase or decrease is controlled by the fine/coarse control. Fine (F) or Coarse (C) Control This button determines the increment/decrement associated with the UP/DOWN arrows. Fine produces small steps in value, while Coarse provides large steps in value. Clicking on the button will toggle the setting.
8-11 Crossover Figure 8-3 Two-way crossover component. Custom crossovers other than those available from the crossover component can be constructed by using the filter component. Crossovers (see Figure 8-3) are used to divide the audio signal into multiple bands appropriate for different types of loudspeakers or loudspeaker elements. In QuickMAPs, 2-way, 3-way, and 4-way crossovers may exist.
8-12 The lowpass filter LP1 and the highpass filter HP1 may each be independently configured as: Bessel 6 dB/octave (1st-order) Bessel 12 dB/octave (2nd-order) Bessel 18 dB/octave (3rd-order) Bessel 24 dB/octave (4th-order) Butterworth 6 dB/octave (1st-order) Butterworth 12 dB/octave (2nd-order) Butterworth 18 dB/octave (3rd-order) Butterworth 24 dB/octave (4th-order) Linkwitz-Riley (Butterworth-Squared) 12 dB/octave (2nd-order) Linkwitz-Riley (Butterworth-Squared) 24 dB/octave (4th-order) In addition, the
8-13 Two-way Linkwitz-Riley Crossovers Linkwitz-Riley designs constitute a special, even-order in-phase class of two-way sum-to-allpass response crossovers, and they must be configured in accordance with very strict phase and polarity requirements.
8-14 implementation of Linkwitz-Riley crossovers, for which the ISP-100 has been optimized. The filters marked optional in Figure 8-5 will be explained in the Linkwitz-Riley Crossover section, below.
8-15 In the ISP-100, 3-way Bessel and Butterworth crossovers are implemented as shown in Figure 8-6. Bessel crossovers utilize Bessel filters. Bessel filters are designed for maximally-flat group delay, meaning that they have nearly linear phase and excellent transient response. Their amplitude response is not as flat and their cutoff is not as sharp as those of Butterworth filters. Butterworth crossovers utilize Butterworth filters.
8-16 band and LP2 lowpass filter in the low band. The inclusion of these filters is mandatory for proper implementation of the 3-way Linkwitz-Riley crossover; they ensure that the phase shift and magnitude response in each band match those of the other bands to maintain the fundamental Linkwitz-Riley sum-to-allpass quality. A detailed explanation of the use of compensation filters such as these may be found in “Active Realization of Multiway All-Pass Crossover Systems” by Joseph A.
8-17 Four-Way Crossovers Figure 8-8 Four-way crossover implementation. In the ISP-100, 4-way crossovers are implemented as shown in Figure 8-8. This parallel structure was selected over the more common binarytree structure for its suitability to the distribution of filters among multiple DSPs. The parallel structure is also capable of perfect implementation of Linkwitz-Riley crossovers, for which the ISP-100 has been optimized.
8-18 The attenuation in each band is continuously variable from -96 dB and 0 dB, plus mute. The polarity in each band is selectable as + or - (in-phase or out-ofphase). Each band may be bypassed, in which case all of the crossover filters in that band will be bypassed while the crossover filters in the other bands will not be affected. Four-way Bessel and Butterworth Crossovers Figure 8-9 Four-way Bessel & Butterworth crossover implementation.
8-19 Four-way Linkwitz-Riley Crossovers Figure 8-10 Four-way Linkwitz-Riley crossover implementation. In the ISP-100, 4-way Linkwitz-Riley crossovers are implemented as shown in Figure 8-10. Linkwitz-Riley designs constitute a special, even-order in-phase class of 2-way sum-to-allpass response crossovers, and they must be configured in accordance with very strict phase and polarity requirements.
8-20 A properly implemented 2-way, 12 dB/octave Linkwitz-Riley crossover is characterized by: • 2nd-order Linkwitz-Riley (Butterworth-Squared) lowpass filter, -6 dB magnitude response at crossover frequency • 2nd-order Linkwitz-Riley (Butterworth-Squared) highpass filter, -6 dB magnitude response at crossover frequency • polarity of highpass band opposite that of lowpass band In a 4-way crossover the bands associate in non-obvious ways (see Sum-to-Allpass Characteristics of Linkwitz-Riley Crossovers).
8-21 depending upon whether 12 dB/octave or 24 dB/octave filters are used, respectively. The following sections will show this sum-to-allpass trait to hold true for the ISP-100 Linkwitz-Riley 3-way and 4-way crossover implementations. Three-way From Figure 8-6 Summed Response = LP1LP2 ± HP1LP2 ± θ1HP2 = (LP1 ± HP1)LP2 ± θ1HP2 = θ1LP2 ± θ 1HP2 = θ1(LP2 ± HP2) = θ1θ2 Q.E.D.
8-22 Class To change settings, click on the arrow next to the number in the text box. A selection list will appear. The list may or may not be scrollable. To make a selection click on the desired entry. Cutoff Frequency The Cutoff Frequency can be adjusted three ways: Using the Knob Click on the indicator on the knob and while continuing to hold down the mouse button, move the mouse in an arc. The numbers in the box below the knob will change. When the desired level is reached, release the mouse button.
8-23 Fine (F) or Coarse (C) Control This button determines the increment/decrement associated with the UP/DOWN arrows. Fine produces small steps in value, while Coarse provides large steps in value. Clicking on the button will toggle the setting. Polarity Control (+/-) This button determines the polarity of the signal. A + indicates that the signal will not have it’s phase altered. A - indicates that the signal’s phase will be changed 180°. Clicking on the button will toggle the setting.
8-24 Cut Figure 8-11 Cut component. The Cut (see Figure 8-11) can apply as much as 96 dB attenuation, or mute completely, and invert polarity. Attenuation and Polarity Application of attenuation is accomplished by multiplying each data sample by a number whose absolute value lies between 1.0 (0 dB) and 0.000015625 (-96 dB). Muting is accomplished by multiplying each sample by zero. Polarity inversion is accomplished by multiplying by a negative number.
8-25 Fine (F) or Coarse (C) Control This button determines the increment/decrement associated with the UP/DOWN arrows. Fine produces small steps in value, while Coarse provides large steps in value. Clicking on the button will toggle the setting. Polarity Control (+/-) This button determines the polarity of the signal. A + indicates that the signal will not have it’s phase altered. A - indicates that the signal’s phase will be changed 180. Clicking on the button will toggle the setting.
8-26 Delay Figure 8-12 Delay component. Delay (see Figure 8-12) is used to compensate for differences in the physical alignment of loudspeakers or loudspeaker drivers. In the ISP-100, the delay in each output channel is adjustable in the range 0 – 2,500 milliseconds (depending on QuickMAP used) in 20.833 microsecond (single sample) increments. This translates to approximately (0 - 2750 feet) in 0.275 inch increments, assuming that the speed of sound is approximately 1100 ft/sec.
8-27 Dither Figure 8-13 Dither component. Dithering (see Figure 8-13) is used when shortening high resolution digital audio data words to a lower resolution; for example, when sending 24-bit ISP-100 audio data to 20-bit D/A converters, or directly to a 16-bit Digital Audio Tape recorder through a digital interface. Simply truncating, or discarding, the unused bits results in audible artifacts that are generally objectionable.
8-28 numbers between 16 and 24 bits, inclusive. The bit level of the dither signal should be set to the bit resolution of the destination for the data. The resulting dither signal will have an amplitude equal to ±1.0 quantization level (peak-to-peak) at the selected Bit Level. Using the examples, the bit level for the dither signal should be set to 20 bits when the data are destined for the 20-bit D/A converters, and to 16 bits when the data are destined for the DAT recorder.
8-29 Filter Figure 8-14 Filter component. The filter component can be used to implement custom crossovers. Filters (see Figure 8-14) are used to modify the spectral balance, frequency content, or phase response of the signals upon which they operate. Filter Bands The filters in the ISP-100 are arranged in bands, each of which represent a single 2nd-order filter in the DSP code.
8-30 All filters in the ISP-100 are derived from analog prototypes. The analog filters are approximated by the Bilinear Transform method, prewarped to match response at the critical frequency appropriate for the type of filter (cutoff frequency for LowPass/HighPass and Peaked HighPass; hinge frequency for LowShelf/HighShelf; center frequency for all others). Each filter band may be bypassed; so as to pass the signal unaltered. LowPass Filters LowPass Filters pass low frequencies and stop high frequencies.
8-31 In the ISP-100 highpass filters the passband slope is selectable from 6 dB/octave, 12 dB/octave, 18 dB/octave, and 24 dB/octave for the Bessel and Butterworth types, and from 12 dB/octave and 24 dB/ octave for the Linkwitz-Riley type. NOTE: Linkwitz-Riley filters are also known as Butterworth-Squared filters because they are the product of two Butterworth filters.
8-32 The hinge frequency is defined as the frequency at which the magnitude of the filter response is changed by (approximately) 3 dB relative to the unfiltered signal. In the ISP-100 highshelf filters the hinge frequency is continuously variable from 20Hz to 20 kHz. In the ISP-100 highshelf filters the transition band slope is selectable from 6 dB/octave and 12 dB/octave. In the ISP-100 highshelf filters the boost/cut is continuously variable from -12 dB to +12 dB.
8-33 The EQ filters in the ISP-100 are full parametric. Each may be adjusted for center frequency, boost or cut, and bandwidth. Center Frequency The center frequency is the frequency at which the maximum boost or cut takes place. In the ISP-100 EQ filters the center frequency is continuously variable from 20 Hz to 20 kHz. Bandwidth can be displayed in terms of Q or octave fraction. See page 7-3 for information on changing the way filter bandwidth is displayed.
8-34 In the ISP-100 EQ filters the bandwidth is continuously variable from 1/12 octave to 3 octaves (which translates to Q between 17.3 and 0.404). Boost and Cut In the ISP-100 EQ filters the boost/cut is continuously variable from +12 dB to -12 dB. Peaked HighPass Filters The Peaked HighPass filter supplied with the ISP-100 is designed to provide bass boost appropriate for low frequency extension in vented-box loudspeakers.
8-35 Cutoff Frequency The cutoff frequency is the design frequency of the highpass filter, and is only approximately representative of the location of the magnitude peak. In the ISP-100 the cutoff frequency is continuously variable from 20 Hz to 20 kHz. AllPass Filters AllPass Filters shift phase without altering magnitude. The allpass filters supplied with the ISP-100 are designed to provide phase compensation for multiway Linkwitz-Riley crossover networks.
8-36 text box without pressing the Enter key will cause the setting to return to the number that it was before a change was attempted. Alternatively, click and drag across the number in the box to highlight the number in it. Type the new setting and press the Enter key when finished. Using the UP/DOWN Arrows To increase the level, click on the up arrow. To decrease the level attenuation, click on the down arrow. The amount of increase or decrease is controlled by the fine/coarse control.
8-37 Alternatively, click and drag across the number in the box to highlight the number in it. Type the new setting and press the Enter key when finished. Using the UP/DOWN Arrows To increase the level, click on the up arrow. To decrease the level attenuation, click on the down arrow. The amount of increase or decrease is controlled by the fine/coarse control. Using the Filter Tool Right-click on the red dot on the active filter band.
8-38 Fine (F) or Coarse (C) Control This button determines the increment/decrement associated with the UP/DOWN arrows. Fine produces small steps in value, while Coarse provides large steps in value. Clicking on the button will toggle the setting. Isolate (Iso) Control This button allows the user to toggle between viewing either the composite response of all active filters in the filter bank or the composite response of an individual filter. Clicking on the button will toggle the setting.
8-39 Gain Figure 8-17 Gain component. Gain (see Figure 8-17) is the first function applied to all ISP-100 input data. The gain component performs many operations, including metering of raw input data (pre-fader), application of up to 18 dB gain, 96 dB attenuation, or full-muting, metering of data after the level has been changed (post-fader), and polarity inversion. Metering Gain includes peak-reading meters.
8-40 to 0 dB and its polarity to positive (in-phase). Bypassing in a muted channel un-mutes it. Metering The meter located at the left of the component measures level in dBFS. The meter’s level will turn red 3 dB before clipping. The red clip light is located at the top of the meter. The green signal present light is located at the bottom of the meter.
8-41 (i.e. after the master attenuator). A green LED indicates that the meter information is pre-fader. Clicking on the button will toggle the setting.
8-42 Gate Figure 8-18 Gate component. A gate (see Figure 8-18) is used in situations where the input signal is characterized by long periods of silence and a noticeably high noise floor, such as a signal taken from magnetic tape or from an open microphone. Gating is accomplished by attenuating the output signal during the periods of input silence in order to reduce the audibility of the noise. Familiar Controls Most of the controls in the ISP-100 Gate are common to nearly all traditional noise gates.
8-43 Closing Time A gate monitors the level of the input signal and controls the level of the output signal accordingly. When the average input signal level decreases from above threshold to below, a gate closes (applies attenuation) so that the output signal level is less than the input signal level. A gate generally sounds better if it is forced to ramp the output signal level to its new value gradually rather than instantaneously. The Closing Time control adjusts the duration of this ramp.
8-44 Detection Window is adjustable in the range 20 µSec (one sample) to 5 Sec. Metering The gate meter shows the attenuation applied to the signal passing through the gate at any given moment in time. When the signal is below threshold and the gate is closed, the meter indicates negative values (gain less than 1.0). When the signal is above threshold and the gate is open, the meter indicates 0 dB (gain of 1.0). Meter values are raw, no averaging or ballistics are applied.
8-45 Alternatively, click and drag across the number in the box to highlight the number in it. Type the new setting and press the Enter key when finished. Using the UP/DOWN Arrows To increase the level, click on the up arrow. To decrease the level attenuation, click on the down arrow. The amount of increase or decrease is controlled by the fine/coarse control.
8-46 Limiter Figure 8-19 Limiter component. A limiter (see Figure 8-18) is used in situations where the output signal must not exceed a given level, regardless of any increase in the level of the input signal. Limiting is often used for system protection purposes, such as the avoidance of amplifier clipping or the prevention of mechanical or thermal damage to loudspeaker components. Familiar Controls Most of the controls in the ISP-100 Limiter are common to nearly all traditional dynamic range limiters.
8-47 Release Time A limiter monitors the level of the input signal and controls the level of the output signal accordingly. When the input signal level suddenly decreases, a limiter allows the output signal level to also decrease only as much as is appropriate, given the relationship between the new input signal level and the threshold setting. A limiter generally sounds better if it is forced to ramp the output signal level to its new value gradually rather than instantaneously.
8-48 Unfamiliar Controls There are two controls on the ISP-100 limiter that are not available in traditional dynamic range limiters. These controls provide much greater flexibility and utility to this limiter than can be achieved with traditional limiters. Detection Window The detection window is the period of time over which the limiter computes the average signal level. Every dynamic range limiter that operates upon average signal level uses a detection window.
8-49 one. The two quantities are then compared and the larger is returned as the signal level. When the Crest Factor Sensitivity is set to 0.00 the ISP-100 limiter operates as a traditional limiter responding to average signal levels; when the Crest Factor Sensitivity is set to 1.00 the ISP-100 limiter operates as a traditional limiter responding to peak signal levels. Values in-between represent various hybrids of the two.
8-50 Computation of Average Level There are two common methods of computing average signal level; one is based upon RMS (Root Mean Square) calculations, and the other is based upon Absolute Value calculations. Each of these methods produces a slightly different value for signal level, and the difference depends upon the characteristics of the signal itself.
8-51 increase or decrease is controlled by the fine/coarse control. Attack, Window, Release, and Crest factor controls. All of these controls can be adjusted in three ways: Using the Knob Click on the indicator on the knob and while continuing to hold down the mouse button, move the mouse in an arc. The numbers in the box below the knob will change. When the desired level is reached, release the mouse button. Using the Text Box Click in the box.
8-52 Select Figure 8-20 Select component. The select function (see Figure 8-20) allows you to set the source that feeds portions of a QuickMAP. The user is allowed to select from as many inputs as the QuickMAP allows. An entire QuickMAP can be fed from a single source or multiple sources depending on the settings of the Selects within the QuickMAP. Note: The amount of available sources is determined by the QuickMAP and not the hardware configuration.
A-1 GLOSSARY A to D Analog to Digital. Conversion of an analog signal to a digital representation. Amplitude factor See CREST FACTOR. Attack The rise of a musical note from zero to full volume. Attack time The time required for an applied signal that suddenly increases in amplitude to reach 1-(1/e), that is, 63.2% of its final, stable value. Attenuate To reduce in amplitude. Attenuation characteristic The decrease of signal amplitude versus frequency.
A-2 Cut To reduce a signal’s overall amplitude. D to A Digital to Analog. Conversion of a digital representation to an analog equivalent signal. dBFS Decibels with respect to digital full scale. The full scale amplitude (zero dBFS value) is the peak value of a sinewave whose positive or negative peak just full scale. reaches dBm dB relative to a reference value of 1 milliwatt.
A-3 Gate A device or circuit which has no output until it is triggered into operation by one or more enabling signals, or until an input signal exceeds a predetermined threshold amplitude. Limiter A device or circuit whose output-signal amplitude remains at some predetermined level in spite of wide variations of input-signal amplitude. Limiting The restriction of the maximum peak amplitude of a signal to a designated level. Muting The act of preventing signal from being output. Phase shift 1.
A-4 THIS PAGE LEFT BLANK INTENTIONALLY 10 July 1998
B-1 STANDARD QUICKMAPS VUE-IT ships with eighteen standard QuickMAPs. These mappings were designed to be flexible enough to be applied in a wide variety of signal processing applications. This appendix provides drawings of the QuickMAPs for reference purposes. The drawings begin on page B-2. Identification of Slots and Connectors The slots and connectors used are indicated by either the word IN in the case of an input or OUT in the case of an output.
B-2 MONDOEQ.
B-3 2X6CMBC.
B-4 2X8COMB.
B-5 3X6CMBC.
B-6 2X8THRU.
B-7 4CHAN.
B-8 4X6CMBC.
B-9 4X6THRU.
B-10 3_2W.
B-11 2WAYS.
B-12 2_3WAY.
B-13 2_2W_SUB.
B-14 2_2W_FR.
B-15 2_2W_2ST.
B-16 4_2WAYS.
B-17 4W_2FR.
B-18 LCR.
B-19 MONO3W.
Copyright © 1997—98 TELEX Communications, Inc. All Rights Reserved. Printed in USA 9600 Aldrich Avenue South Minneapolis, MN 49107 USA Ph. 612.884.4051 Fax 612.887.5588 7/98 P/N: 38109-744 Rev.
