Optimod-PCn

Optimod-quality digital audio processing
Running natively on an Intel x86 computer, pre-processes audio for consistency and loudness before it is streamed, encoded, transmitted or recorded.

Live and file content audio processing
Provides live streaming and offline, faster-than-real-time file processing. Can simultaneously stream live while processing files.
File processing preserves metadata that may be present in sources files, and passes to destination files.

Available in mono/stereo and surround versions
One security key supports up to 16 audio processors, which may be any combination of mono/stereo and surround processors.

Applications
Live stream netcasting, file based streaming, podcast production, DAB and other dedicated digital radio services, FMExtra™ and other digital subcarriers, sound-for-picture, mastering, audio production, and many others.

Can be used as a pre-processor for existing hardware Optimod processors, adding features like parallel compression and the “Multipath Mitigator” phase corrector.

High Density Typologies
Using the appropriate computer hardware and CPUs, multiple instances of Optimod-PCn may be run on a single system, increasing processing hardware density to unprecedented levels. With currently available single CPU systems, typical densities are upwards of 16 instances in a 1RU form factor. Multiple CPU systems go upwards from there. This dramatically relieves rack space requirements and allows for redundancy accommodation.
Target Loudness

A “Target Loudness” control and built-in BS.1770 loudness meter make it easy to comply with modern loudness control recommendations and regulations. But BS.1770 control alone has a “genre” problem: speech normalized to the same target loudness as music inevitably sounds too loud. The Orban loudness controller cascades a CBS Loudness Controller with a “BS.1770 Safety Limiter.” The CBS controller does the heavy lifting, balancing all genres consistently and automatically. If you need to constrain the reading of a BS.1770 meter due to government regulation or corporate policy, you can activate the BS.1770 Safety Limiter for this purpose, knowing that the upstream CBS controller will prevent speech from becoming too loud.

More and more netcasters want to comply with loudness control recommendations such as EBU R-128, ATSC A/85, and the Audio Engineering Society “Recommendation for Loudness of Audio Streaming and Network File Playback.” These rely on Integrated ITU-R BS.1770-4 loudness measurements to define a long-term “target loudness” so that listeners don’t have to adjust their volume controls when switching between streams. Optimod-PCn provides a “Target Loudness” control and BS.1770 loudness meter that make it easy to comply. The best way is to put Optimod-PCn inline and let it control loudness smoothly and automatically in real time, with proper handling of segues and crossfades between program elements. If this is impossible, the next best option is using Optimod-PCn offline file processing ability to loudness-normalize each file in your playout system independently.

Orban Optimod is the only processing that offers loudness management technology based on the CBS Loudness Meter and Loudness Controller, developed at CBS Technology Center. By using a more sophisticated psychoacoustic model than BS.1770, the CBS technology solves the BS.1770 “genre problem”: According to the AES Recommendation, “Speech normalized to the same [BS.1770] Integrated Loudness as a music stream inevitably sounds too loud. It is recommended to normalize speech (dialog) segments within other segments 2 to 4 LU (or more) below the loudness of the other segments.”

The Orban Loudness Controller is a two-stage process. It starts with a CBS Loudness Controller, which does almost all of the work and provides excellent subjective balance between speech and music without needing “genre offsets.” A “BS.1770 Safety Limiter” follows. You can adjust its threshold anywhere from 0 to +6 LU above the Target Loudness. We included it mainly for the sake of organizations that rely on the BS.1770 meter to verify compliance with government loudness regulations. Because of the genre limitations in the BS.1770 algorithm itself, the Safety Limiter can make material that has been “artistically compressed” in production sound too quiet. Therefore, we prefer the sound of the CBS algorithm by itself and recommend that users set the BS.1770 Safety Limiter threshold as high as possible while still complying with relevant regulations.

Windows Service
The audio processor runs as a Windows Service on its host computer, so it will start automatically with Windows without a login, and run reliably in the background.

Dedicated GUI
A responsive, smooth, easy-to-use graphic control application runs on local or remote PCs and can control any number of OPTIMOD-PCn audio Processors, either locally (via a localhost TCP/IP connection) or in other Optimod-PCns on your network via TCP/IP addressing. The Control application allows you complete flexibility to create your own custom presets, to save as many as you want to local storage, and to recall them at will.

Windows Sound Devices
Compatible with all Windows sound devices with stable Windows WASAPI Drivers. Supports real, virtual, and network audio devices for maximum connection flexibility, scalability, and inter-app audio connections without real hardware. For example, systems with playout software, Optimod-PCn, and streaming encoders running on the same computer, do not require hardware sound devices. Optimod-PCn does NOT require a special DSP sound card, dramatically decreasing deployment costs, since additional PCIe slots are NOT required for multiple processors.

Network Audio
By use of third party Windows Audio drivers, is compatible with network audio input/output (such as Lawo R3LAY/Ravenna®, Axia LiveWire®, Audinate Dante®, and Wheatstone WheatNet®).

Precise Peak Control
Precisely controls peak levels to prevent over-modulation or codec overload. While primarily oriented toward “flat” media, OPTIMOD-PCn can also provide pre-emphasis limiting for the two standard pre-emphasis curves of 50µs and 75µs. This allows it to protect pre-emphasized satellite uplinks and similar channels where protection limiting or light processing is required. It can also be used to process analog television FM aural carriers in television applications because these are usually processed lightly compared to FM radio.

Coded Audio Processing
Orban 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. 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 pre-processed by other processing than Optimod.

Audio Bandwidth Control
Controls audio bandwidth as necessary to accommodate the transmitted sampling frequency, obviating the need for extra, overshooting anti-aliasing filters in downstream equipment. OPTIMOD-PCn’s high frequency bandwidth can be switched instantly (typically in 1 kHz increments) between 10.0 kHz and 20 kHz. 20 kHz is used for highest-quality systems. 15 kHz codec bandwidth may help low bitrate lossy codecs sound better than they do when fed full 20 kHz bandwidth audio. 15 kHz is well matched to the codec used the iBiquity® HD-AM system.

Intended for program equalization and mastering, a sweepable gentle-slope lowpass filter (6 to 24 dB/octave) is available in addition to the sharp-cutoff lowpass filter.

For specialized purposes like speech processing, a sweepable highpass filter with four selectable slopes (6 to 24 dB/octave) is available. Music and speech modes have separate cutoff frequencies and slopes, so the automatic speech/music detector can change filter characteristics.

The highpass and lowpass filters provide click-free switching of their cutoff frequencies, so they these may be changed in the middle of program material.

DC Removal Filter
A DC removal filter with a 0.1 Hz −3 dB low frequency cutoff removes DC offset from source material without introducing overshoot and tilt into low-frequency waveforms.

Audio Processing Presets
OPTIMOD-PCn includes many standard presets, designed to accommodate almost any programming format. There are also special-purpose, no-compromise presets for mastering and pure peak limiting.

Bypass/Test Mode
A Bypass Test Mode facilitates broadcast system test and alignment tests.

Audio Line-up Generator
OPTIMOD-PCn contains a built-in line-up tone generator, facilitating quick and accurate level setting in any system. Low-distortion sinewave, non-overshooting squarewave, and high-precision pink noise test signals are available.

Smooth Activate/Defeat
Audio processing can be smoothly activated and defeated on-air via a delay-matched pass-through mode, allowing programs that can benefit from full dynamic range to pass through OPTIMOD-PCn without dynamics compression except for safety limiting using MX or non-MX limiter modes.

Software Security Protection
USB key security protection allows the software to be easily moved from one computer to another without elaborate re-authorization procedures. No Internet connection is required. The graphic control application is not copy-protected and can be installed on an unlimited number of computers.

Audio Processing Features

Increase Density and Loudness
OPTIMOD-PCn can increase the density and loudness of the program material by multiband compression and sophisticated peak limiting, improving the consistency of the station’s sound and increasing loudness and definition remarkably, without producing unpleasant side effects.

Phase/Delay Correction
Automatic left/right phase-skew corrector can eliminate comb-filtering artifacts in a mono downmix. Effectively removes Haeco-CSG processing and re-channeled stereo created with 90° phase difference networks. This increases mono compatibility insuring equal loudness between mono and stereo sources. Also corrects complete out-of-phase mono and stereo sources. This is more important than ever with the millions of mono mobile devices in use today. When used as a preprocessor for Optimod-FM, it can reduce multipath distortion by minimizing energy in the stereo subchannel, which carries the L–R signal.

LF/Bass Mono
Bass can be made monophonic, with crossover frequencies of 80 or 100 Hz.

Two-Band AGC
Two-Band automatic gain control with a phase-linear crossover, adjustable band coupling, and window gating compensates for widely varying input levels. The AGC rides gain over an adjustable range of up to 25dB, compressing dynamic range and compensating for operator gain-riding errors and for gain inconsistencies in automated systems.

Five-Band Compression
Five-Band compression with steep, selectable phase-linear and allpass crossover topologies provides a consistent, “unprocessed” or “processed” sound, free from undesirable side effects.

Band-coupling controls allow the gain differences between adjacent bands of the five-band compressor to be constrained to any desired value, allowing you to preserve as much of the frequency balance of the original program material as desired unless doing so would otherwise cause objectionable spectral gain intermodulation artifacts. Combined with the phase-linear crossover, this functionality can be used in lieu of the two-band compression found in earlier Optimods.

Parametric soft-knee compression curves with adjustable ratio allow you to fine-tune the audio to your exact requirements and make OPTIMOD-PCn an excellent mastering processor.

The five-band compressor can be operated in both inline and parallel modes. Parallel mode drives downstream processing with the sum of the input and output of the multiband compressor. This increases the loudness of quiet material while preserving the dynamics and punch of loud material. Typical applications include preparing classical music for in-flight entertainment or other noisy environments, or as preprocessor for Optimod-FM.

Stereo Enhancement
Stereo Enhancer is based on Orban’s patented analog 222 Stereo Enhancer, which increases the energy in the stereo difference signal (L−R) whenever a transient is detected in the stereo sum signal (L+R). Gating circuitry prevents over-enhancement and undesired enhancement on slightly unbalanced mono material. Complements the Optimix upmixer, increasing the sense of envelopment and space while maintaining excellent downmix compatibility.

Audio Equalization
Shelving bass equalizer and four-band parametric equalizer let you color the audio to your exact requirements. To facilitate A/B comparisons, equalizers can be bypassed individually and globally.

Dynamic High-Frequency Enhancer
Dynamic High-Frequency Enhancer constantly monitors the ratio of HF to broadband energy in the incoming audio and can automatically re-equalize it to achieve a target balance between broadband and HF energy.

High Performance Peak Limiter
Orban’s exclusive MX peak limiter technology uses a psychoacoustic model to achieve an unprecedentedly favorable tradeoff between loudness, transient punch, and distortion artifacts.

For applications where target loudness is below approximately −12 LKFS/LUFS, you can reduce CPU load by approximately 50% without compromising audio quality (compared to full MX limiter operation) by defeating the MX limiter and instead using Orban’s smooth, low-IM look-ahead limiter for the very light peak limiting required at these low loudness levels. This is the normal mode of operation for sound-for-picture applications, where target loudness is typically −23 LUFS or −24 LUFS and peak limiting rarely occurs at all.

In all modes of operation, the peak limiter offers “true peak” control by oversampling the peak limiter’s sidechain at 384 kHz. This allows OPTIMOD-PCn to prevent clipping in a playback device’s analog signal path by predicting and controlling the analog peak level following the playback device’s reconstruction filter.

Without true peak control, analog clipping can occur even if all peak values of the digital samples are below 0 dBFS. This phenomenon has also been termed “0 dBFS+.”

Due to true peak control, sample rate conversion, unless it removes high frequency program energy or introduces group delay distortion, cannot cause sample peaks to increase more than 0.5 dB. For example, sample rate conversion from 48 kHz to 44.1 kHz is highly unlikely to cause sample peak clipping in the 44.1 kHz audio data.

Accuracy is typically 0.15 dB even with heavy peak limiting, so the output level can be set to −0.2 dBFS without true peak levels exceeding 0 dBFS.

2.0 to 5.1 Upmixer
Second-generation Optimix™ stereo 5.0 surround upmixer provides uncolored automatic upmixing, plus phase correction that ensures that the center channel is always crisp and intelligible. 5.1-compatible. Provides excellent downmix compatibility. Can wrap the virtual soundstage around the listener (put the listener “in the middle of the band”) or place the stage primarily in the front (put the listener “in the audience”).

1.0 to 2.0 Upmixer – Stereo Synthesizer
Orban Stereo Synthesizer with excellent downmix compatibility. “Wide” and “narrow” modes (based on the Orban classic analog 275A Stereo Synthesizer) can create an attractively spacious stereo or surround output from mono program material. Synthesis can be invoked manually, or activated automatically by sensing silence in the right channel input.

CBS Loudness Controller
OPTIMOD-PCn includes third-generation CBS Loudness Controllers™ for DTV applications. Separate loudness controllers are available in both the surround and downmix processing chains. 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. Material processed by the CBS Loudness Controller has been shown to be well controlled when measured with a long-term loudness meter using the BS.1770 standard.

BS.1770 Loudness Controller
A BS.1770 Safety Limiter follows the CBS Loudness Controller, When activated, it 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.

Loudness Meters
BS.1770-4 and CBS Loudness Meters™ measure the subjective loudness of the OPTIMOD-PCn output and are displayed in the OPTIMOD-PCn control application meter window. When downmix processing is active, there are two independent loudness controllers and two loudness meters available.

High-Performance Mastering Peak Limiter Mode
A pure peak limiting preset is available. It allows OPTIMOD-PCn to perform very high quality peak limiting in mastering applications.

AGC Protection Mode
OPTIMOD-PCn can be used as a studio AGC (including peak limiting) to protect a studio-to-transmitter link (STL), optimally using the STL’s native dynamic range, or to protect during production while recording.

Multi-Rate Digital Signal Processing
Uses “multirate” digital signal processing. Internal processing always occurs at sample rates from 48 kHz to 256 kHz as needed, and provides 20 kHz audio bandwidth (unless specifically constrained by the user-adjustable lowpass filter). Built-in high-quality synchronous sample rate converters facilitate interfacing with 44.1 kHz, 96 kHz and 192 kHz systems.

Floating-Point Digital Signal Processing
Uses 32-bit or 64-bit floating-point arithmetic as appropriate. Better precision than fixed-point DSP.
Can interface to 16-bit and 24-bit Windows audio devices.

Virtual Environment Qualified
Virtual machine compatible with:
VMware
VirtualBox
XenServer
Parallels Desktop for Mac
CrossOver Mac
USB Key must run on virtual machine bare metal