Studio Technologies 58 User Manual

for Surround
Model 58 Central Controller and
User Guide
Issue 2, April 1998
This User Guide is applicable for serial numbers:
Model 58 M58-00151 and later Model 59 M59-00151 and later
© 1998 by Studio Technologies, Inc., all rights reserved
5520 West Touhy Avenue
Skokie, Illinois 60077 U.S.A.
Telephone (847) 676-9177
Fax (847) 982-0747
www.studio-tech.com
50079-498, Issue 2
for Surround
Tab le of Contents
Foreword..................................................................... 5
Introduction ................................................................. 7
What This User Guide Covers ................................ 7
StudioComm for Surround ...................................... 7
Model 58 Central Controller .................................... 7
Model 59 Control Console....................................... 8
Applications................................................................. 11
Installation................................................................... 15
Configuration............................................................... 21
Operation .................................................................... 37
Technical Notes .......................................................... 40
Specifications .............................................................. 42
Appendix A
Controlling the Model 58 ......................................... 4 3
MIDI Messages ....................................................... 44
Appendix B
Model 58 Single-Channel Mode.............................. 5 2
Appendix C
Block Diagrams
Model 58 Central Controller
Model 59 Control Console
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Forew ord
Simply stated: I had a blast working on the StudioComm for Surround components! It is very rewarding to develop a set of products for a market that’s actually receptive to new ideas and supportive of innovation.
A big thanks to Jeff Levison, formerly of Warner Hollywood Studios. He patiently answered our questions over a period of many months, helping to guide us in the right direction. I recently read an interesting book on the history of the Warner Brothers and their movie empire. One of the things that stood out was their long-term commitment to audio. From the Jazz Singer to the current DVD releases, they haven’t been afraid of staying on the forefront of sound for picture. Good going guys!
Mitch Budniak designed much of the hardware and kept us out of “digital trouble.” Carrie Loving provided engineering support and designed the product graphics. Larry Leviton wrote the excellent software that makes the hardware “come to life.” Fred Roeck per­formed the mechanical design. Al “PCB PRO” Lux designed the...you guessed it! Joe Urbanczyk coordinated the safety testing and created the automated test routes for our Audio Precision System Ones.
Our plans are to continue with other StudioComm for Surround components. Your praise, comments, or complaints are encouraged, helping to keep us going in the right direction. Please contact me via E-mail at gkapes@studio-tech.com.
Sincerely,
Gordon K. Kapes President
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Introduction
What This User Guide Covers
This User Guide is designed to assist you when installing and using the Model 58 Central Controller and the Model 59 Con­trol Console. A limited amount of trouble­shooting information is also provided. Should you require detailed technical information please refer to the Service Guide covering the Models 58 and 59. The Service Guide contains detailed service information, including schematic diagrams. The Service Guide is not shipped with each StudioComm for Surround system, but is available from the factory upon request. It is free of charge to purchasers of StudioComm for Surround equipment. Call, send a fax, or E-mail us if you need this highly exciting document!
location. Using a single 9-pin cable, a Model 59 connects to up to four Model 58 Central Controllers. Each Model 58 sup­ports four 2-channel inputs and two output channels in a single rack space. By select­ing two, three, or four Model 58s, 4-, 6-, or 8-channel systems can be created.
The Models 58 and 59 were developed in conjunction with experts in the post-pro­duction audio field. The overall goal turned out to be very straightforward: provide the necessary technical performance and features, while keeping it simple to oper­ate! Be certain that users won’t have to go through a long “learning curve” before they become efficient. Allow the StudioComm for Surround system to be flexible, but not so much as to hinder the “big picture.” The end result achieves these goals, providing extensive capability in a simple-to-operate format.
StudioComm for Surround
As the production of multi-channel “sur­round sound” audio material becomes more prevalent, the need for monitoring these sources becomes imperative for more and more facilities. Whether it’s 4-, 6-, or 8-channel formats, a means to select input sources, insert support de­vices into the audio path, and control the output level to monitor loudspeakers is required. Studio Technologies has ad­dressed this need with the StudioComm for Surround Model 58 Central Controller and Model 59 Control Console. Using these components a system can be con­figured to meet a facility’s exact monitoring requirements.
A StudioComm for Surround system starts with a Model 59 Control Console, a com­pact but comfortable “command center,” that is designed to reside at the operator’s
Model 58 Central Controller
The Model 58 Central Controller is a single rack-space unit that supports two output channels. Multiple Model 58s are con­nected together to achieve 4-, 6-, or 8­channel systems. Each Model 58 provides eight inputs, organized as four 2-channel pairs. Two 2-channel insert sections allow connection to external processing equip­ment, specifically surround-sound en­coder-decoder units. The insert sections can also be used for special applications, such as creating a phantom center chan­nel, or used as part of a PLF/solo support function. The 2-channel monitor output section is switched, using electromechani­cal relays, to allow connection of two separate loudspeaker systems. Protection circuitry provides power-up and power­down protection for the loudspeakers. A 2-channel meter output provides a
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“reference” signal, and is not affected by the monitor output’s level-control circuitry.
The inputs, inserts, and monitor outputs are electronically balanced, while the meter outputs are unbalanced. Fifteen-turn trim potentiometers are used to precisely calibrate the input, insert return, and moni­tor output signals. Audio input, insert, and output connections are made using three 25-pin D-subminiature connectors. The connectors follow an industry-standard multi-channel wiring scheme. Two 9-pin D-subminiature connectors are used in a simple loop-through arrangement to con­nect the Model 58 to a Model 59 Control Console, as well as to additional Model 58 units.
An 8-bit micro-controller provides the logic “horsepower” for the Model 58. DIP switches are used to select the Model 58’s unit ID and operating mode. AC mains power is connected directly to the Model 58, which is factory selected for 100, 120, 220/240V operation. The internal power supply utilizes a toroidal mains transformer for quiet audio operation.
Model 59 Control Console
The Model 59 Control Console is a com­pact, self-contained unit designed to be located at the operator’s position. It allows fingertip control of all monitoring param­eters. Numerous LEDs provide complete status information. The Model 59 supports up to eight output channels, and up to four, 8-channel input sources. The actual
Figure 1. Model 58 Central Controller Front Panel
Input
trimpots
Insert 1
return trimpots
Figure 2. Model 58 Central Controller Back Panel
AC mains
connection
To/from
Model 59
Control
Console
to additional
return trimpots
Loop thru
connector
Model 58
Insert 2
Monitor out
trim pots
connections
Output
Insert
connections
Configuration DIP switches
Data
active LED
Input
connections
Power
present LED
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Mute/solo
mode select
Inserts 1 & 2
Input
Sources
1-4
for Surround
Output channel
mute/solo
Remote control input activity LED
Monitor Output
• Output A/B select
• Reference level
• Mute all
• Dim
• Rotary level control
Figure 3. Model 59 Control Console Front Panel
operating configuration simply depends on the number of Model 58 Central Controller units which are connected.
The Model 59 provides four buttons and associated LEDs for selection of the input source to be monitored. While in most cases only one input source will be moni­tored at a time, multiple inputs can be selected for simultaneous monitoring. This allows two, three, or all four of the inputs to be combined (“summed”). While there is no independent control of the input levels, this feature can be useful for creat­ing rough mixes from the source signals. It is also a fast, effective means of making a “seat-of-the-pants” check on the phase relationship between synchronized signals.
The monitor output level is controlled either through the use of a large, easy­to-use rotary control, or by enabling the
preset reference level. For operator con­venience, the dim function allows the monitor output level to be reduced by a fixed dB amount. The mute all function disables all monitor outputs by activating the mute relays on the Model 58 Central Controller units. A push-button switch and two LEDs are used to select the desired monitor output—either A or B.
The StudioComm’s two insert sections are directly accessible using push-button switches. While they can perform a stan­dard insert action, they can also be used to provide a wide range of muting, routing, and summing functions. Each insert can be configured, on a channel-by-channel basis, to act in one of four modes: Mute, maintain connection of the normal signal, insert the return signal in place of the normal signal, or sum the return signal with the normal signal.
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Control of the individual output channels is provided by the mute/solo section. One push-button switch sets the operating mode for either mute or solo. In the mute mode, individual channels can be muted or un-muted as required. In the solo mode, one channel can be monitored while the others are automatically muted. (Of course, multiple channels can be simulta­neously selected for “soloing.”) The flex­ibility of having both mute and solo available allows an operator to quickly select the most comfortable and produc­tive operating mode.
A major strength of the Model 59 is the ability to configure, under software control, many operating parameters. During initial installation the Model 59 is “taught” the number of output channels to be con­trolled, the number of channels associated with each of the four inputs, and the rout­ing to be performed by the insert sections. The monitor output reference level is set
by taking an electronic “snapshot” of the position of the rotary level control. The dim level is selected from among four choices. A number of other operating parameters can also be configured, including how the remote contact and level control inputs will function. All configuration parameters are stored in non-volatile memory.
A Model 59 Control Console connects to a Model 58 Central Controller using a standard 9-pin D-subminiature cable. Multiple Model 58 units connect together in a bus fashion. Power for the Model 59 is provided by the Model 58s. The Model 59 generates MIDI system-exclusive messages to control the Model 58 units. Remote control signals connect to the Model 59 via pins in the 9-pin intercon­necting cable.
Remote Control Capability
Three remote control functions can be easily implemented: Mute all or dim, insert
Figure 4. Multi-Channel Monitor System Showing Four Model 58 Central Controllers Interconnected with Bus Assembly
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1 or 2 enable, and monitor level. Contact input 1 can be configured as either a remote mute all or a remote dim function. This supports external functions such as talk back or slate. Contact input 2 can be used to remotely enable insert 1 or 2, allowing the PFL/solo function on an audio console to be interfaced with the Studio­Comm for Surround system. Using a standard linear-taper potentiometer, a remote level control can be implemented; no special optical encoder or buffer cir­cuitry is required. The remote control functions allow creation of a secondary monitoring position, such as a producer’s or director’s desk or seating location where level control or muting may be desired. Provisions have been made in the StudioComm’s operating software to ensure that critical listening is not affected by remote activity.
Expanded Input Capability
In the standard operating mode the Model 59 Control Console is designed to support up to four Model 58 Central Controller units. This provides eight output channels, and allows connection of up to four 8­channel sources. A special mode can be enabled that lets a slightly modified Model 59 support up to eight Model 58 units. This mode will again support eight output channels, but will now allow connection of up to eight 8-channel sources. Special­ized playback applications, such as large screening rooms at motion picture studios, can benefit from this expanded operating mode. Contact the factory for details.
Limitations on Signal Routing
While a StudioComm for Surround system for multi-channel monitoring will do many wonderful things, it is not designed to selectively route input signals to the differ-
ent output channels. An input-channel-to­output-channel relationship is maintained. A signal that arrives on input 2, channel 6 will, when selected, output only on monitor and meter output channel 6. Any rerouting of the input signals must be done prior to connection to the StudioComm for Surround system. This should not be an impairment in most facilities, but it’s important to highlight this fact.
Applications
Configuration Examples
It can initially be confusing to fully under­stand how a Model 59 Control Console and multiple Model 58 Central Controllers work together to create a multi-channel monitor system. How the input and output channels are assigned to the Model 58 units can seem especially tricky. In this section several examples are provided that should present a clear picture of how things go together. A careful review of the associated diagrams should quickly make you feel more comfortable. The flexibility of the StudioComm for Surround system is both a blessing and a curse. A simpler system would make installation a “no brainer,” but in the long run having the ability to achieve your operational goals is of overriding importance.
6-Channel (5.1) Configuration
Figure 5 provides an overview of a typical 6-channel installation. The channels are organized in the standard 5.1 arrange­ment: left, center, right, left surround, right surround, and sub. The sub or subwoofer channel is sometimes referred to as the LFE (low frequency enhancement) chan­nel. (The term LFE is actually more de­scriptive but, as of this writing, isn’t as
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commonly used.) Two 6-channel audio sources and one set of amplified monitor loudspeakers are connected. Note care­fully how the channels are assigned: Model 58 unit 1 supports the left channel and the center channel, Model 58 unit 2 supports the right channel and the left surround channel, and Model 58 unit 3 supports the right surround channel and the subwoofer channel. Three input and three output wiring harnesses are re­quired, each connecting to the Model 58s with 25-pin D-subminiature plugs. These wiring harnesses are not included with the StudioComm for Surround system.
The Model 59 Control Console is con­nected to Model 58 unit 1 using a 9-pin
“D-sub” interconnecting cable. The three Model 58 units are linked together using the ribbon cable bus assembly. Both the 9-pin interconnecting cable and ribbon cable bus are provided with the Studio­Comm for Surround system. AC mains power needs to be connected to each of the three Model 58s. In this example installation many of the available re­sources are not utilized, including the third and fourth 6-channel inputs, the insert sections, the meter outputs, and the remote control functions.
4-Channel (LCRS) Configuration
Figure 6 shows a 4-channel installation that follows the traditional LCRS format:
Figure 5. Example of 6-Channel (5.1) Configuration
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Figure 6. Example of 4-Channel (LCRS) Configuration
left, center, right, and surround. Again, two 4-channel sources are connected, along with one set of amplified loudspeak­ers. The left and center channels are supported by Model 58 unit 1, while the right and surround channels are supported by Model 58 unit 2. A processor device is connected to one of the insert sections on both Model 58 units. Two input, two insert, and two output wiring harnesses are utilized for audio interconnection.
The Model 59 Control Console is con­nected to Model 58 unit 1, and both Model 58s are interconnected using the ribbon cable bus assembly. AC mains power must be connected to both Model 58 units. Many features are available for future use, including inputs 3 and 4, the second insert section, the meter outputs, and the remote control functions.
Inserts
The Model 58 insert sections are appli­cable for far more than the usual console inserts functions. Under control of the Model 59 Control Console, each insert channel can independently function in one of four modes: mute normal signal flow, maintain the normal signal flow, replace the normal signal with the return signal, or sum (combine) the return signal with the normal signal. (Note that in all cases the insert send signal will remain active.) With this flexibility the inserts can be used for a variety of insert, routing, and mixing functions.
Using the insert returns, in conjunction with contact input 2, allows a console’s AFL/solo system to be directly integrated. The console’s source of AFL/solo audio
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(usually the stereo monitor output) can be connected to the insert returns associated with the left and right channels. With this arrangement, whenever the console’s AFL/solo system is active, the audio will automatically be monitored, overriding the normal audio source. (Refer to the remote control input paragraphs of the Installation section for details on connecting to contact input 2.)
The decision as to which insert section to utilize for an AFL/solo function depends on how the AFL/solo signal should flow through the system; pre or post, relative to the other insert section. In most cases using insert 2 is preferable, ensuring that the AFL/solo signal will not be processed by insert 1.
A “phantom” center channel can be easily created by connecting the insert send of a surround channel to the insert returns on the channels designated for left and right. However, with this implementation, a level “buildup” problem may occur. If this is the case, the source of the phantom center may need to be attenuated by 6dB (volt­age). This would be easily accomplished using a resistor “pad” to drop the level. With the insert sends capable of driving 600 ohm loads, a simple three resistor pad would work well; two 150 ohm and one 300 ohm resistor would do the trick.
Remote Control
Provision has been made to allow remote control of several operating parameters. Contact input 1 allows remote activation of the mute all or dim functions. Contact input 2 allows remote activation of the insert 1 or insert 2 functions. The level control input allows remote control of the monitor output level. The exact functioning
of the remote inputs is dependent on the configuration of Model 59 Control Console parameters. Refer to the Configuration section of this guide for details.
Remote control of mute all or dim is pro­vided to allow a variety of applications to be supported. Placing a mechanical switch adjacent to a telephone, allowing person­nel to conveniently mute the monitor loudspeakers, is a perfectly acceptable application. Allowing a talk-back system to automatically dim the monitors is another typical application.
Remote control of insert 1 or insert 2 was specifically provided to support interfacing with an associated console’s PFL/solo system. By connecting to an electronic signal that indicates when the PFL/solo system is active, audio signals connected to insert return 1 or 2 will be automatically monitored.
The remote level control input is one of those features which is rarely going to be used, but if you need it, you’ll really need it! (Without having support built into the Model 59 Control Console’s hardware and software, it would be almost impossible to add a remote level control later.) The remote level control input was provided specifically to allow a producer, director, or other “big cheese” to have their own level control for use when previewing motion picture or video work-in-process. The remote level control input, along with the remote mute all and dim functions, makes it simple to create a small control console for secondary locations.
Note that software “smarts” in the Model 59 Control Console inhibits the use of the remote level control any time the operator selects the reference output level. This
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ensures that the calibrated monitor level won’t accidentally be changed by some maroon. This, along with a remote activity LED indicator on the Model 59, keeps the remote level control from doing more harm than good.
Installation
In this section you will be installing the one or more Model 58 Central Controllers in an equipment rack. Multiple Model 58 units will be interconnected using the bus as­sembly. Audio input, insert, and output connections will be made. A location will be selected for the Model 59 Control Console, and it will be connected to one of the Model 58 units. If required, external equipment will be interfaced with the remote control inputs. AC mains power will be connected to the Model 58 units.
System Components
The main shipping carton contains the Model 58/Model 59 base configuration. This consists of one each of the following: Model 58 Central Controller, Model 59 Control Console, 20-foot (6.1m) 9-pin D-subminiature interconnecting cable, ribbon-cable bus assembly, User Guide, and warranty card. Units destined for North America also include an AC mains cord. Your dealer or distributor will provide an AC mains cord for non-North American destination. Each additional Model 58 Central Controller is shipped in a separate carton. These Model 58 “solo” units in­clude a warranty card and, where appli­cable, an AC mains cord.
Mounting Model 58 Central Controllers
Each Model 58 Central Controller requires one space in a standard 19-inch (48.3cm) equipment rack. Select a location that is convenient to both the analog audio sig­nals and the Model 59 Control Console. A 20-foot (6.1m) cable is supplied to connect the Model 58 units to the Model
59. You can supply your own interconnect­ing cable, however 50 feet (15.3m) is the recommended maximum length. Secure each Model 58 in the equipment rack using two mounting screws per side.
Consider selecting a mounting location that can accommodate future expansion. If, for example, you are installing three Model 58 units to create a 6-channel system, you may want to leave room in the rack for one additional Model 58. This will make upgrading to an 8-channel system simple; install a fourth Model 58 and you’re ready to go.
Interconnecting the Model 58 Units
In most applications multiple Model 58 units are going to be used together to create a multi-channel monitor system. To assist in this purpose, a ribbon-cable bus assembly is provided with each Model 58/ Model 59 base configuration. The bus assembly contains four 9-pin D-sub plugs, spaced 2 inches apart, allowing up to four Model 58s to be interconnected. Refer to Figure 4 for a diagram depicting the inter­connection of four Model 58 units. Each Model 58 contains a 9-pin D-sub connec­tor labeled LOOP THRU. Use the bus assembly to link these connectors to­gether. Locking hardware for the plugs is not included as it is unnecessary for
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reliable interconnection. (If you are the compulsive type, the D-subs on the Model 58 use 4-40 threads.)
Audio Input, Output and Insert Connections
Audio input and output connections are made by way of three 25-pin D-subminia­ture (“D-sub”) connectors. Located on the Model 58’s back panel, the connectors are labeled INPUTS, INSERTS, and OUT­PUTS. Three cable harnesses, each with a 25-pin D-sub plug (male) on one end, and the desired connectors on the other end, are necessary. These cable har­nesses are not supplied by Studio Tech­nologies.
The wiring scheme used by the D-subs comply with that made familiar by TASCAM with their DA-88 product. A wiring harness prepared for the Model 58 input channels would be identical to that of a DA-88 input harness. A wiring har­ness prepared for the Model 58 output channels would be identical to that of a DA-88 output harness. A harness for the Model 58 inserts and outputs would be wired in a slightly different fashion. Please refer to Figures 7, 8, and 9 for exact con­nection details. Note that the Model 58’s D-sub connectors use 4-40 threads.
When it came time for Studio Technolo­gies to test the first Model 58 Central Controller, standard DA-88 harnesses were purchased. They turned out to be of very good quality, and at a reasonable price. Unless there’s a special need, it may be cost and time effective for you to purchase commercially made cable as­semblies. Let the large market for DA-88­style cabling help you painlessly install your system!
Line Inputs
The connector labeled INPUTS is used to interface with the eight line input circuits. Please refer to Figure 7 for details on the exact “pin out” of the D-sub connector. The electronically balanced input circuitry is intended for connection to balanced or unbalanced sources with a nominal signal level of +4dBu. A trim potentiometer is associated with each input, allowing ad­justment of the input sensitivity over a ±2dB range. The configuration sections of this guide provides details on using the trim pots.
Balanced sources should be wired so that signal high is connected to + on the D-sub, signal low to – on the D-sub, and shield to the D-sub’s shield connection. With an unbalanced source connect signal high to the + connection on the D-sub, and shield to both the – and the shield connection on the D-sub. If connecting to an unbalanced source in this manner results in hum or
Signal Signal
Connection High (+) Low (–) Shield
IN 1-1 24 12 25 IN 1-2 10 23 11 IN 2-1 21 9 22 IN 2-2 7 20 8 IN 3-1 18 6 19 IN 3-2 4 17 5 IN 4-1 15 3 16 IN 4-2 1 14 2
Notes: 1) Connector type on Model 58 is 25-pin
D-subminiature female. Installer must provide plug (male). Connector uses 4-40 threaded inserts for locking with mating plug.
2) Wiring scheme follows Tascam DA-88 convention. Standard DA-88-type wiring harnesses are directly compatible, with the exception of 4-40 screw threads being required.
Figure 7. Connector Pin Out for Inputs
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noise, connect signal high to + on the D-sub, and shield to – on the D-sub; leave the shield connection on the D-sub unterminated.
It is important that at least one of the multi-channel inputs be wired by way of an audio patch bay. This will allow the chan­nels associated with an input source to be easily rerouted. While signals generated within a facility will usually follow a specific format, such as L, C, R, LS, RS, Sub, it is possible that media provided by an outside source will follow a different one.
Outputs
The connector labeled OUTPUTS pro­vides access to the two, 2-channel monitor outputs and the 2-channel meter output. Please refer to Figure 8 for details on the exact “pin out” of the D-sub connector.
Signal Signal
Connection High (+) Low (–) Shield
MONITOR A-1 24 12 25 MONITOR A-2 10 23 11 MONITOR B-1 21 9 22 MONITOR B-2 7 20 8
METER 1 18 6 (See Note 3) 19
METER 2 4 17 (See Note 3) 5 NOT USED 15 3 16 NOT USED 1 14 2
Notes: 1) Connector type on Model 58 is 25-pin
D-subminiature female. Installer must provide plug (male). Connector uses 4-40 threaded inserts for locking with mating plug.
2) Wiring scheme loosely follows Tascam DA-88 convention. Modified DA-88-type wiring harnesses are required, along with 4-40 screw threads.
3) Meter outputs are unbalanced. Pins 6 and 17 internally connected to Model 58 shield.
Figure 8. Connector Pin Out for Outputs
The monitor outputs are intended for connection to audio amplifiers associated with monitor loudspeakers, or to the inputs of loudspeakers with integrated amplifiers. Note that there are two monitor output circuits which are switched, using relays, to the 2-channel A and B output connec­tions. Under normal operation only one set of outputs, A or B, will be active at the same time. The output which is not active has a short-circuit placed across its connections.
Note: While the electronically balanced output circuits are capable of driving loads of 600 ohms or greater, the out­put level will drop slightly as the load impedance approaches 600 ohms. A
0.5dB difference in output level can be expected as the load impedance changes from 10k ohms to 600 ohms. This applies to all of the electronically balanced output circuits provided on the Model 58.
The monitor outputs are electronically balanced and are capable of driving bal­anced or unbalanced loads of 600 ohms or greater. While balanced operation is preferred, unbalanced operation does not pose a problem. To connect to an unbal­anced load connect the + terminal of the D-sub as signal high, and both the – and shield as the signal low/shield. For optimal unbalanced operation, it is important to connect both – and shield together directly on the D-sub, and not at the other end of the harness.
The same source, or sources, that feed the monitor outputs are fed to meter out­puts. The major difference is that the meter outputs are not affected by the
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