Orban Optimod 8585
Orban Optimod 8585
Experience has shown that the mass television audience wants two things from television audio: dialog should be comfortably intelligible and commercials should not be irritatingly loud compared to program material. Home theater owners may want the opportunity to watch feature films while hearing a wide dynamic range signal. However, even these viewers usually consume television in a much more passive way when viewing garden-variety programs. To be an acceptable part of the domestic environment, television sound cannot overwhelm household members not interested in viewing (not to mention neighbors, particularly in multi-family dwellings). For a variety of reasons, the dynamic range of sound essential to the intelligibility of the program should not exceed 15 dB in a domestic listening environment. Underscoring and ambient sound effects will, of course, be lower than this.
The issue of loud commercials is particularly important. In the U.S., it is against Federal Communications Commission rules to broadcast irritatingly loud commercials. As a result of viewer complaints, the FCC has twice investigated the problem.
Orban understands such issues well. Since 1980, we have provided analog television broadcasters with industry-standard dynamics processors: OPTIMOD-TV 8180, 8182, 8282 and 8382. In 1998, we introduced OPTIMOD-DAB 6200—two-channel processing specifically tailored for digital channels using lossy compression like Dolby's AC-3, which is used for ATSC transmissions. Our 6300, introduced in 2006, is a second-generation two-channel processor for digital channels, including DTV, DAB and netcasting.
In typical analog television practice, all audio is applied to a single transmission audio processor that automatically controls the average modulation and the peak-to-average ratio while smoothing out transitions between program elements. Simple compression and peak limiting cannot do this effectively.
Starting with the 8182, all OPTIMOD-TV processors have incorporated the CBS Loudness Controller™. Developed after 15 years of psychoacoustic research at CBS Laboratories, the CBS LC accurately estimates the amount of perceived loudness in a given piece of program material. If the loudness exceeds a preset threshold, the controller automatically reduces it to that threshold. The CBS algorithm has proven its effectiveness by processing millions of hours of on-air programming and greatly reducing viewer complaints.
In ITU parlance, the CBS LC relies on a "short-term" loudness measurement that takes into account the human ear's loudness integration time—approximately 200 milliseconds. The CBS algorithm's attack time is fast enough to prevent audible and irritating loudness overshoots—blasts of sound that have viewers scrambling for their remote controls. Loudness control is always smooth and unobtrusive. Unlike "long-term" loudness measurement and control technologies, the CBS LC recognizes that a piece of program material whose average loudness seems acceptable according to a long-term loudness measurement may nevertheless have short sections whose loudness should be reduced because it is extremely annoying. While main purpose of this processing is to control the loudness of commercials, other exuberantly mixed elements can also benefit. (A good example is applause with whistling.)
Effective Automatic Loudness Control for Up to 7.1 Channels
For many years our television customers have been asking for OPTIMOD-quality surround sound processing along with the ability to process the local insertion of news, weather and sports independently. Our customers know that there is no substitute for the smooth, natural-sounding control that only OPTIMOD provides, particularly with speech material.
Orban's response is the 8585. This next generation OPTIMOD provides the function and control necessary for up to eight channels simultaneously. It can help you achieve the highest audience satisfaction in digital audio broadcasting, digital television and netcasting.
The 8585 features OPTIMOD-quality two-band and five-band audio processing for surround sound broadcasting and netcasting. Thanks to versatile compression ratio controls and a mastering-quality look-ahead peak limiter, the 8585 is also ideal for mastering audio in broadcast productions as well as productions intended for media such as DVD and Blu-ray.
The 8585 starts with the technology of Orban's popular OPTIMOD 6300 and takes it to the next level with surround processing that reflects the latest psychoacoustic research into loudness perception. The 8585's CBS Loudness Controller works in both two-band and five-band modes. Third generation improvements reduce annoyance better than simple loudness control alone, doing so without audible gain pumping.
The 8585 is two processors in one, offering surround processing for either 7.1 channels or 5.1 channels plus an independent 2.0 channel processor (equivalent to OPTIMOD 6300 processing) that can operate stand-alone with its own CBS Loudness Controller. Additionally, the 2.0 processor's output can be mixed into the left and right front channels of the surround processing so that the surround processing's Loudness Controller and look-ahead limiters control the loudness and peak level of the mix. Built-in CBS Loudness Meters indicate the subjective loudness of the surround and 2.0 channel processing.
The multichannel and 2.0 processors can operate with separate audio processing parameters like release times. For example, the 2.0 processing could be set up for relatively heavy processing to make a newsroom feed more consistent, while the main processing was set up more conservatively to correct network material and commercials unobtrusively.
Because the 2.0 processing has its own loudness controller and peak limiters, another important application is processing subchannels in digital television. The 2.0 processing can operate in dual-mono mode, so it can process one subchannel in stereo or two subchannels in mono.
The 8585 is built on Orban's flagship hardware platform. This features a GUI displayed on a quarter-VGA active matrix color LCD, making it easy to do all setup and adjustment from the 8585's front panel. To minimize latency and to achieve highest reliability, the 8585 uses a dual hardware architecture. Freescale 24-bit DSP chips do all audio processing while a separate microcontroller supports the GUI and control functions. Even if this controller malfunctions, the 8585 will continue to process audio normally.
Minimum latency of the fully processed signal is 21 milliseconds, which can be padded to exactly one frame delay for any video standard. The low latency headphone feed (containing all processing except for peak limiting) has a latency of approximately 6 milliseconds
Technical Specifications
Frequency Response
(Bypass Mode)
Surround Processing: ±0.10 dB, 20 Hz - 20 kHz for 44.1 kHz or higher input/output sample rates. At 32 kHz input and/or output sample rate, the passband is reduced to approximately 14.7 kHz.
2.0 Processing: Depending on settings, is flat or follows standard 50 µs or 75 µs preemphasis curve ±0.10 dB, 20 Hz - 20 kHz (except at 32 kHz; see above). Output can be user-configured to be flat or pre-emphasized. (Pre-emphasis limiting is offered to accommodate certain older analog studio/transmitter links.)
Noise Output noise floor will depend upon how much gain the processor is set for (Limit Drive, AGC Drive, Two-Band Drive and/or Multiband Drive), gating level, equalization, noise reduction, etc. The noise floor of the digital input signal primarily governs it. The dynamic range of the 8585's digital signal processing is greater than 100 dB.
Processing Sample Rate 48 kHz. We believe this provides maximum audible transparency by minimizing numerical "noise" in the equalizers and filters while still preserving a pure, transparent sound. The double-precision equalizers and crossover filters used throughout the 8585 produce at least 6 dB lower noise and nonlinear distortion than they would at 96 kHz.
Processing Resolution Internal processing has 24 bit (fixed point) or higher resolution; uses 12 Freescale (formerly Motorola) 150 MHz DSP56367 DSP chips.
Delay The minimum available input/output delay is approximately 21 ms with look-ahead limiting active and 6 ms with look-ahead limiting bypassed. This can be padded to exactly one frame of 24, 25, 29.97 or 30 frames / second video up to a maximum delay of 50 ms.
Surround Processing Stereo Coupling All channels of the AGC and compressors are coupled using r.m.s. summation. The user can select whether or not the LFE channel contributes to the r.m.s. sum in the AGC and compressor control sidechains. Peak limiters in the multiband compressor limiter and look-ahead limiters all operate uncoupled to prevent transients in a given channel from causing audible loudness modulation in other channels.
2.0 Processing Stereo Coupling Stereo or dual-mono. In dual-mono mode, both processing channels have the same subjective adjustments (as determined by the active preset) but are otherwise independent, making this mode appropriate for dual-language transmissions. In stereo mode, the user can set the maximum permitted gain difference between the channels in each band of the multiband compressor/limiter. 2.0 Stereo/Dual-Mono operating mode can be set via GPI, Ethernet and serial connections, internal clock-based automation and AES3 Status Bits.
Loudness Level Meter (x2) One meter for the surround processing and one meter for the 2.0 processing, both meters realized in software. Meter can be displayed on the 8585's front-panel screen and on its PC Remote software. In ITU terminology, this meter measures "short-term" loudness. Its display time constants are matched to the loudness integration time of the human ear, reaching steady-state level in approximately 200 ms and having a decay time constant of approximately 300 ms. Meter uses the Jones & Torick algorithm developed at CBS Technology Center and published in the 9/1981 issue of the SMPTE Journal, pp. 772-777.
Digital Audio Inputs (x5)
Configuration Each of five hardware inputs accepts two audio channels per AES3id standard, 24 bit resolution. Internal programmable routing switcher allows any of the 10 physical input channels to be routed to the LF, RF, C, LB1, RB1, LFE, LB2, RB2, STEREO L or STEREO R inputs of the audio processing. For the 2.0 processing, unit can detect Stereo or Two-Channel status bits appearing at Input #1 and switch the 2.0 processor between stereo and dual-mono modes.
Sampling Rate 32, 44.1, 48, 88.2 or 96 kHz, automatically selected.
Connectors BNC, female, transformer-coupled, shell bypassed to chassis via 1000 pF capacitor, EMI-suppressed. 75ω impedance, terminated.
Input Reference Level Variable within the range of -30 dBfs to -10 dBfs.
Filtering RFI filtered.
Digital Audio Outputs (x6)
Configuration AES3id. Internal, remote-controllable routing switcher allows sending LF, RF, C, LB1, RB1, LFE, LB2, RB2, STEREO L, STEREO R, DOWNMIX L and DOWNMIX R to any hardware output channel. J.17 pre-emphasis can be applied to digital audio output.
Sample Rate Internal free running at 32, 44.1, 48, 88.1 or 96 kHz, selected in software. Can also be synced to the AES3id Input #1,or to the sync input (which supports AES11id and wordclock) at 32, 44.1, 48, 88.1 or 96 kHz, as configured in software. (Passband is limited to approximately 14.7 kHz when using 32 kHz input and/or output sample rate.)
Word Length Software selected for 24, 20, 18 or 16-bit resolution. First-order high-pass noise-shaped dither can be optionally added, Dither level is automatically adjusted to complement the word length.
Connectors BNC, female, transformer-coupled, shell bypassed to chassis via 1000 pF capacitor, EMI-suppressed. 75ω impedance.
Output Level (100% peak modulation) -20.0 to 0.0 dBfs software controlled.
Filtering RFI filtered.
Analog Audio Outputs
Configuration One pair of outputs, which can be configured in software to emit LF, RF, C, LB1, RB1, LFE, LB2, RB2, STEREO L, STEREO R, DOWNMIX L, DOWNMIX R, LF/RF, C, LB1/RB1, LB2/RB2, STEREO L/R and DOWNMIX L/R signals.
Source Impedance 50μ, electronically balanced and floating.
Load Impedance 600μ or greater, balanced or unbalanced. Termination not required or recommended.
Output Level
(100% peak modulation) Adjustable from -6 dBu to +24 dBu peak, into 600ω or greater load, software-adjustable.
Signal-to-Noise =100 dB unweighted (Bypass mode, 20 Hz - 20 kHz bandwidth, referenced to 100% modulation).
Distortion =0.01% THD (Bypass mode, de-emphasized) 20 Hz - 20 kHz bandwidth.
Connectors Two XLR-type, male, EMI-suppressed. Pin 1 chassis ground, Pins 2 (+) and 3 electronically balanced, floating and symmetrical.
D/A Conversion 24 bit 128x oversampled.
Filtering RFI filtered.
Sync Input
Configuration Can accept wordclock or AES11id (75ω) sync, automatically selected.
Connector Female BNC, shell bypassed to chassis via 1000 pF capacitor, transformer-coupled.
Termination Unterminated. Use an external 75ω terminator if the 8585 is the last item in the chain.
Remote Computer Interface
Configuration TCP/IP protocol via direct cable connect, modem, or Ethernet interface. Modem is not supplied.
Serial Port 115 kbps RS232 port DB-9 male, EMI-suppressed.
Ethernet Port 100 Mbit/sec on RJ45 female connector.
RS485 Serial Interface (x2)
Hardware 115 kbps RS485 port DB-9 male, EMI-suppressed.
Compatibility Hardware-compatible with Dolby Digital® hardware that sends and receives Dolby Digital metadata.
Remote Control (GPI) Interface
Configuration Eight (8) inputs, opto-isolated and floating.
Voltage 6 - 15 V AC or DC, momentary or continuous.
12 VDC provided to facilitate use with contact closure.
Connector DB-25 male, EMI-suppressed.
Control User-programmable for any eight of user presets, factory presets, bypass, test tone, stereo or mono modes, analog input, digital input.
Filtering RFI filtered.
Tally Outputs
Circuit Configuration Two NPN open-collector outputs.
Voltage +15 Volts maximum. Do not apply negative voltage. When driving a relay or other inductive load, connect a diode in reverse polarity across the relay coil to protect the driver transistors from reverse voltage caused by inductive kickback.
Current 30 mA maximum.
Indications Tally outputs can be programmed to indicate a number of different operational and fault conditions.
Power
Voltage 100 - 132 VAC or 200 - 264 VAC, switch-selected on the rear panel, 50 - 60 Hz, 50 VA.
Connector IEC, EMI-suppressed. Detachable 3-wire power cord supplied.
Safety Standards ETL listed to UL standards, CE marked.
Environmental
Operating Temperature 32 to 122 °F / 0 to 50 °C for all operating voltage ranges.
Humidity 0 - 95% RH, non-condensing.
Dimensions (W x H x D) 19" x 5.25" x 15.5" / 48.3 cm x 8.9 cm x 39.4 cm. Depth shown indicates rack penetration; overall front-to-back depth is 17.75" / 45.1 cm. Three rack units high.
RFI / EMI Tested according to Cenelec procedures. FCC Part 15 Class A device.
Shipping Weight 40 lbs. / 18.1 kg
Warranty
Two Years, Parts and Service Subject to the limitations set forth in Orban's Standard Warranty Agreement.
