For over 30 years, Optimod-AM has dominated the sound of major market AM radio. The 9400 distills all of Orban’s experience into the best Optimod-AM ever!
Orban’s all-digital 9400 OPTIMOD-AM Audio Processor can help you achieve the highest possible quality in AM shortwave, medium wave and long wave broadcast sound. OPTIMOD-AM delivers louder, cleaner, brighter, FM like audio with an open, fatigue free quality that attracts listeners and holds them. OPTIMOD-AM was designed to deliver a high quality FM-like sound to the listener’s ear by pre-processing for the limitations of the average car or table radio.
The 9400 supports iBiquity’s HD AM® in-band on-channel digital radio system. The digital radio processing can also be used for simulcast netcast, DAB+, DRM or DRM+ digital broadcasts. Regardless of whether you have a major-market station or just want your station to sound like one, Optimod-AM 9400 is right for you.
Making the Most of the AM Channel
The 9400 is suitable for long wave, medium wave, and shortwave (HF) broadcasts.
OPTIMOD-AM 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.
OPTIMOD-AM increases the density and loudness of the program material by multiband limiting and multiband distortion canceling clipping, improving the consistency of the station’s sound and increasing loudness and definition without producing audible side effects. OPTIMOD-AM precisely controls peak levelsto prevent over-modulation. Asymmetry in the analog processing channel is adjustable from 100% to 150% positive peak modulation.
OPTIMOD-AM compensates for the high- and low frequency roll-offs of typical AM receivers with a fully adjustable program equalizer providing up to 20dB of high-frequency boost (at 5 kHz) without producing the side effects encountered in conventional processors. This equalizer can thus produce extreme pre-emphasis that is appropriate for very narrow-band radios. OPTIMOD-AM’s fully parametric low- and mid-frequency equalizers allow you to tailor your air your precise requirements and desires. OPTIMOD-AM also fully supports the NRSC standard pre-emphasis curve.
OPTIMOD-AM is a stereo processor that fully protects CQUAM® transmissions, conservatively complying with Motorola’s processing requirements that negative peak modulation on the left and right channels be limited to –75% modulation. The 9400 comes with a wide variety of factory presets to accommodate almost any user requirement. The user can readily modify these presets or customize them with easy one-knob LESS-MORE control. Modified presets can be stored and recalled on command. Advanced Control (accessible from the PC Remote application) facilitates detailed sound design using the same controls that were available to the factory programmers. Quick Setup guides you through 9400 setup for your primary analog AM transmitter. It is appropriate for users with modern transmitter plants and without special requirements such as setting up HD Radio processing or CQUAM AM stereo processing.
OPTIMOD-AM supports the iBiquity HD Radio® system, DAB+, DRM and DRM+ digital broadcast. Except for common stereo enhancement and AGC, the HD AM processor is an independent processing chain with its own set of user-adjustable parameters, maintaining 15 kHz audio bandwidth (per iBiquity’s specifications) regardless of the bandwidth setting of the processing intended for the analog channel. To ensure source-to-source consistency, the digital radio processing includes full fiveband compression/limiting that is independent of the five-band compression/limiting in the analog processing chain. This output can also be used for netcasts, cable, and satellite radio. 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. There are several HD factory presets tuned specifically for low bitrate codecs. These presets have “LBR” in their names.
Optimal Control of Peak Modulation Levels
The analog AM audio processing circuitry in OPTIMOD-AM produces a waveform that is precisely peak-controlled to prevent over-modulation, and is low-pass filtered to protect adjacent channels and to conform to government regulations. The output of the digital radio-processing path is also precisely peak-controlled at the 9400’s output. However, the HDC codec used in the HD AM system and the AAC-Plus (HE –AAC) codec used in the DRM system, like all low bitrate lossy codecs, introduce considerable overshoots as a side effect of throwing away data. When you adjust the drive level into the codec, it is wise to monitor the output of a radio or modulation monitor and to reduce the drive level to the codec until you no longer see clipping.
The 9400 controls the transmitted bandwidth of the analog channel to meet government regulations, regardless of program material or equalization. The high frequency bandwidth of the analog processing channel can be switched instantly in 500Hz increments between 4.5 kHz and 9.5 kHz (NRSC). The lower cutoff frequencies meet the output power spectral density requirements of ITU-R 328-5 without further low-pass filtering at the transmitter, while the 9.5 kHz filter meets the requirements of the NRSC-1 standard (North America). The 5.0 kHz filter makes the analog AM bandwidth compatible with HD AM transmission. The low-pass filters have parametric cutoff shapes, allowing you to trade off filter ringing against frequency response flatness. OPTIMOD-AM compensates for inaccuracies in the pulse response (tilt, overshoot, ringing) of transmitters and antenna systems with a powerful four-parameter transmitter equalizer. A built in squarewave generator makes adjustment easy. Four sets of equalizer parameters can be stored and recalled, allowing you to program day and night variations for two transmitters. You can set equalization independently in the stereo sum and difference channels, facilitating adjustment in CQUAM AM stereo facilities. The 9400 includes analog and AES3 digital inputs. Two sets of analog stereo outputs and two AES3 outputs accommodate as many as four transmitters. Outputs can be switched independently to emit the analog-channel signal, the digital-channel signal, or a low-delay monitor signal suitable for talent headphones. Both the digital input and the two digital outputs are equipped with sample-rate converters and can operate at 32 kHz, 44.1 kHz, 48, 88.2, and 96 kHz sample rates. The output levels are separately adjustable for the analog and digital outputs.
The 9400 is designed and certified to meet all applicable international safety and emissions standards.
Controllable and Adjustable
An LCD and full-time LED meters make setup, adjustment and programming of OPTIMOD-AM easy. You can always see the metering while you’re adjusting the processor. Navigation is by dedicated buttons, soft buttons (whose functions are context-sensitive), and a large rotary knob. The LED’s show all metering functions. OPTIMOD-AM contains a versatile real-time clock, which allows automation of various events (including recalling presets) at pre-programmed times. A Bypass Test Mode can be invoked locally, by remote control (from either the 9400’s GPI port or the 9400 PC Remote application), or by automation to permit broadcast system test and alignment or “proof of performance” tests. OPTIMOD-AM contains a built-in line-up tone generator, facilitating quick and accurate level setting in any system. OPTIMOD-AM’s software can be upgraded by running Orban supplied downloadable upgrade software on a PC. The upgrade can occur remotely through the 9400’s Ethernet port or serial port or locally (by connecting a Windows® computer to the 9400’s serial port through the supplied null modem cable). The 9400 can be remote-controlled by 5-12V pulses applied to eight programmable, optically isolated “general-purpose interface” (GPI) ports.9400 PC Remote software runs under Windows 2000, XP, Vista, 7 and 8. It communicates with a given 9400 via TCP/IP over modem, direct serial, andEthernet connections. The PC Remote software allows the user to access all 9400 features (including advanced controls not available from the 9400’s front panel), and allows the user to archive and restore presets, automation lists, and system.