Optimod 8685 Surround ~ Features
Absolute Control of Loudness and Peak Modulation
- The 8685 includes third-generation CBS Loudness Controllers™ and BS.1770 safety limiters for DTV applications.
- Separate loudness controllers and safety limiters are available in the multichannel and 2.0 processing chains and work with the both the Two-Band and Five-Band structures. The third-generation improvements reduce annoyance more than simple loudness control alone, doing so without audible gain pumping. Attack time is fast enough to prevent audible loudness overshoots, so the control is smooth and unobtrusive. Loudness control is excellent when measured by the ITU BS.1770 or EBU R-128 standards or by the 8685's built-in CBS Loudness Meters, allowing stations to comply effortlessly with the requirements of the CALM act. New in Version 1.1 software is a "BS.1770 Safety Limiter" which can further improve the measured performance using the BS.1770 meter and which was added for the benefit of organizations with strict objective limits on the indication of a BS.1770-2 meter regardless of the actual subjective loudness as determined by human listeners.
Using the ITU BS.1770 and CBS Loudness Meters To Measure Loudness Controller Performance
- Precise control of peak levels
- The 8685 precisely controls peak levels to prevent digital clipping. The maximum level of the digital samples is controlled to better than 2%.
- Pre-emphasis limiting for the two standard pre-emphasis curves of 50 µs & 75 µs
- While primarily oriented toward "flat" media, the 8685's 2.0 channel processors can also provide pre-emphasis limiting for the two standard pre-emphasis curves of 50 µs and 75 µs. This allows them to protect pre-emphasized microwave links, satellite uplinks and similar channels where protection limiting or light processing is required. |Note that the 8685's 2.0 channel processing cannot provide simultaneous, independent audio processing for flat and preemphasized channels. Even though one output may be pre-emphasized while other is flat, the only difference between the outputs is that the "flat" output has de-emphasis applied to it after the processing while the preemphasized output does not.
- Color LCD and large rotary knob
- A large (quarter-VGA) color liquid crystal display (LCD) makes setup, adjustment and programming of the 8500 easy. Navigation is by a miniature joystick, two dedicated buttons, and a large rotary knob. The LCD shows all metering functions of the processing structure in use.
- Navigation Joystick
- Use the Locate joystick to navigate through a menu that lets you recall a preset, modify processing (at three levels of expertise), or to access the system's setup controls.
- Nine processors in one
- A gain-coupled multichannel processor for up to 7.1 channels, plus four additional, independent 2.0 channel processors (whose performance is equivalent to an OPTIMOD 6300) that can be used for many tasks such as processing the audio for a second language and up to three ATSC subchannels. Because its output can be mixed into the LF and RF outputs of the multichannel processing, the primary 2.0 channel processor can also be used to process an independent feed (like the output of a sports truck, news truck, or newsroom) before it is mixed with the station's main multichannel audio path. The audio processing parameters can be set independently for the surround and 2.0 processors. (All 2.0 processors have the same processing parameters.) The 2.0 processors can be operated in dual-mono mode where each mono channel has a dedicated CBS loudness controller, BS.1770 safety limiter, CBS loudness meter, and BS.1770 loudness meter. Hence, the 8685 can simultaneously process up to eight mono audio streams for CALM Act compliance.
- Inputs & Outputs
- The 8685 provides 3G HD-SDI I/O, one (+ loop) video sync reference input, four AES3id inputs, and three AESid outputs. All AES3id inputs and outputs are transformer-coupled, appear on BNC connectors, and have 75 Ω impedance. Audio I/O from both the HD-SDI and AES3id ports includes sample rate converters and can operate at 32, 44.1, 48, 88.2 and 96 kHz sample rates.
- Configurations via remote-controllable internal routing switchers
- OPTIMOD 8685's inputs and outputs are highly configurable via remote-controllable internal routing switchers with scene memory, allowing various configurations to be recalled easily via GPI, clock-based automation, 8685 PC remote software, Ethernet or serial ASCII commands, and the 8685's front panel. Additionally, the outputs of the multichannel and 2.0 processing chains can be independently configured to emit the output of the AGC or the output of the multiband compressor/limiter, all configurable to use or bypass look-ahead limiting.
- Use 8685 as an AES splitter
- Via the internal output routing switcher, a given output signal can be applied to more than one hardware output. This allows using the 8685 as an AES splitter.
- Stereo analog monitor output
- For both the base I/O configuration and the HD-SDI module, a stereo analog monitor output appears on XLR connectors on the rear panel. It can be configured to emit any 8685 output signal, including a downmix of the multichannel audio. The analog outputs are transformerless, balanced, and floating (with 50 Ω impedance) to ensure highest transparency and accurate pulse response. They can be used to drive a transmitter, although their normal function is monitoring.
- Stereo headphone jack
- A stereo headphone jack is available on the front panel. It can be configured to emit any 8685 output signal and is independent of the stereo analog monitor output.
- BS.1770 loudness meter logging
- The 8685 comes with an application for Windows PCs that writes the indications of the 8685's built-in BS 1770 loudness meters to local or network storage. This password-protected application can log the indications whenever the PC is connected to the 8685 via a TCP/IP network. The user can select a logging interval and all readings are time-stamped. The logging application can be configured to automatically send a notification e-mail to a selected address when logging starts or stops.
- Dolby Digital Metadata I/O
- Two RS485 serial ports allow the 8685 to accept and emit Dolby Digital metadata. Metadata can also be de-embedded and re-embedded in the HD-SDI V-AUX area and, if the Dolby E modules are installed, de-embedded from and re-embedded into Dolby E data that is conveyed either through the HD-SDI connection or the AES3id connections.
- Dual-mono mode
- The 8685's 2.0 processing offers a dual-mono mode that allows two entirely separate mono programs to be processed, facilitating multiple-language operation.
In this mode, both processing channels operate using the same processing parameters (like release time); you cannot adjust the two channels to provide different processing textures.
- Sync Input
- An audio sync input is configurable to accept AES11id or wordclock sync. You can synchronize the output samplerate of all AES3id outputs to this input. You can also synchronize the outputs to the AES3 digital input #1 or to the 8685's internal clock.
The sync source of each AES3 output is independently selectable.
- Dual power
- Dual power supplies with independent AC line inputs provide redundant operation.
- All connections are rigorously RFI-suppressed
- All input, output, and power connections are rigorously RFI-suppressed to Orban's traditional exacting standards, ensuring trouble-free installation.
- The 8685 is designed and certified to meet all applicable international safety and emissions standards.
Adaptability through Multiple Audio Processing Structures
- Complete audio processing system
- A processing structure is a program that operates as a complete audio processing system. Only one processing structure can be on-air at a time. OPTIMOD 8685 realizes its processing structures as a series of high-speed mathematical computations made by Digital Signal Processing (DSP) chips.
- Two processing structures
- The 8685 features two processing structures: Five-Band for a spectrally consistent sound and Two-Band for a more transparent sound that preserves the frequency balance of the original program material.
- "Protect" function
- A special Two-Band preset creates a no-compromise "Protect" function that is functionally similar to the "Protect" structures in earlier Orban digital processors.
- Rides gain over an adjustable range of up to 25 dB
- The 8685's AGC rides gain over an adjustable range of up to 25dB, compressing dynamic range and compensating for both operator gain-riding errors and gain inconsistencies in automated systems.
The AGC output is available to drive STLs, so the 8685 can be used as a studio AGC.
- Switching between processing structures and Pass-through mode
- Switching between the Five-Band and the Two-Band audio processing structures occurs via a mute-free crossfade. Additionally, a Pass-through mode can be smoothly invoked without switching artifacts. Pass-through mode passes audio, metadata, and video through without alteration. Delay does not change between Pass-through and active processing modes, thereby maintaining AV-sync.
- Phase-linear processing structures
- The 8685's processing structures are all phase-linear to maximize audible transparency.
- Mastering-quality noise and distortion performance
- The 8685's equalizers and crossovers use 48-bit arithmetic to ensure mastering-quality noise and distortion performance.
- Orban's PreCode™ technology
- Orban's PreCode™ technology manipulates several aspects of the audio to minimize artifacts caused by low bitrate codecs, ensuring consistent loudness and texture from one source to the next. It is particularly useful when processing for netcasts or mastering for any low bitrate channel.
PreCode includes special audio band detection algorithms that are energy and spectrum aware. This can improve codec performance on some codecs by reducing audio processing induced codec artifacts, even with program material that has been preprocessed or mastered by processing other than OPTIMOD. There are several factory presets tuned specifically for low bitrate codecs.
- Eight programmable, optically isolated GPI ports
- The 8685 can be remote-controlled by 5-12 V pulses applied to eight programmable, optically isolated "general-purpose interface" (GPI) ports.
- 8685 PC Remote software
- 8685 PC Remote software is a smooth, responsive graphical application that runs under Windows XP, Vista and 7. It communicates with a given 8685 via TCP/IP over modem, direct serial and Ethernet connections. You can configure PC Remote to switch between many 8685s via a convenient organizer that supports giving any 8685 an alias and supports grouping multiple 8685s into folders. Clicking an 8685's icon causes PC Remote to connect to that 8685 through an Ethernet network or initiates a Windows Dial-Up or Direct Cable Connection if appropriate. The PC Remote software allows the user to access all 8685 features and allows the user to archive and restore presets, automation lists, and system setups (containing I/O levels, digital word lengths, GPI functional assignments, etc.).
- Remote administration over TCP/IP
- An API provides remote administration over TCP/IP via the RS232 serial or Ethernet ports. The 8685 hosts a TCP/IP terminal server to allow external control of the 8685 from either a Telnet/SSH client or a custom third party application. All commands are simple text strings. You can recall presets, operate the input and output routing switchers and more. Password security is provided.
- Versatile real-time clock
- The 8685 contains a versatile real-time clock, which allows automation of various events (including recalling presets) at pre-programmed times. To ensure accuracy, the clock can be synchronized to an Internet timeserver.
- Silence Alarm & Tally Outputs
- Silence alarm and digital audio fault tally outputs are available.
- Bypass Test Mode
- A Bypass Test Mode can be invoked locally, by remote control (from either the 8685's GPI port or the 8685 PC Remote application), or by automation to permit broadcast system test and alignment or "proof of performance" tests.
- Built-in line-up tone generator
- The 8685 contains a built-in line-up tone generator, facilitating quick and accurate level setting in any system.
- Software Upgrade
- The 8685's software can be upgraded by running Orban-supplied downloadable upgrade software on a PC. The upgrade can occur remotely through the 8685's Ethernet port or serial port (connected to an external modem) or locally (by connecting a Windows® computer to the 8685's serial port through the supplied null modem cable).