Features

User-Friendly Interface

An LCD and full-time LED meters make setup, adjustment and programming of OPTIMOD-FM easy—you can always see the metering while you’re adjusting the processor. Navigation is by dedicated buttons, soft buttons (whose function is context- sensitive), and a large rotary knob.

Absolute Control of Peak Modulation

The 2300 provides universal transmitter protection and audio processing for FM broadcast. It can be configured to interface ideally with any commonly found transmission system in the world.
The 2300 provides pre-emphasis limiting for the two standard pre- emphasis curves of 50 µs and 75 µs. Its pre-emphasis control is seldom audibly apparent, producing a clean, open sound with subjective brightness matching the original program.
The 2300 achieves extremely tight peak control at all its outputs — analog Left/Right, AES/EBU Left/Right, and composite baseband.
By integrating the stereo encoder with the audio processing, the 2300 eliminates the overshoot problems that waste valuable modulation in traditional external encoders. The stereo encoder has two outputs with independent level controls, each capable of driving 75 ohms in parallel with 47,000pF, (100ft / 30m of coaxial cable).
The 2300 prevents aliasing distortion in subsequent stereo encoders or transmission links by providing bandwidth-limiting and overshoot-compensated 15 kHz low-pass filters ahead of the 2300’s audio outputs and stereo encoder.

Flexible Configuration

The 2300 includes analog and AES/EBU digital inputs and outputs. Both digital input and digital output are equipped with sample-rate converters and can operate at 32 kHz, 44.1 kHz, 48, 88.2, and 96 kHz sample rates. The pre-emphasis status and output levels are separately adjustable for the analog and digital outputs.
The 2300 has an internal, DSP-based stereo encoder (with a patented “half-cosine interpolation” composite limiter operating at 512 kHz sample rate) to generate the pilot tone stereo baseband signal and control its peak level. This composite limiter is a unique, “you can only do this in DSP” process that beats composite clippers by preserving stereo imaging while fully protecting the stereo pilot tone, RDS / RBDS, and subcarriers.
The analog inputs are transformerless, balanced 10k ohm instrumentation-amplifier circuits, and the analog outputs are transformerless balanced, and floating (with 50 ohm impedance) to ensure highest transparency and accurate pulse response.
The 2300 has two independent composite baseband outputs with digitally programmable output levels. Robust line drivers enable them to drive 100 feet of RG-59 coaxial cable without audible performance degradation.
The 2300 has two subcarrier inputs that are mixed with the output of OPTIMOD-FM’s stereo encoder before application to the composite output connectors. One input can be re-jumpered to provide a 19 kHz pilot reference output. The other input has an internal level trim to accommodate subcarrier generators with output levels as low as 220 mV.
The 2300 precisely controls the audio bandwidth to 15 kHz. This prevents overshoots in uncompressed digital links operating at a 32 kHz-sample rate and prevents interference to the pilot tone and RDS (or RBDS) subcarrier.
The 2300 has a defeatable, patented multiplex power limiter that controls the multiplex power to ITU-R BS412 standards. An adjustable threshold allows a station to achieve maximum legal multiplex power even if the downstream transmission system introduces peak overshoots into the 2300-processed signal. Because this limiter closes a feedback loop around the audio processing, it allows the user to adjust the processor’s subjective setup controls freely without violating BS412 limits, regardless of program material. The multiplex power limiter acts on all outputs (not just the composite output) and works by adjusting the thresholds in the multiband compressor instead of adding another wideband gain control stage. The limiter is thus entirely multiband, which minimizes spectral gain intermodulation. It reduces clipper drive when it reduces power, simultaneously reducing clipping distortion.
All input, output, and power connections are rigorously RFI- suppressed to Orban’s traditional exacting standards, ensuring trouble-free installation.
The 2300 is designed and certified to meet all applicable international safety and emissions standards.
The 2300 features a versatile Two-Band processing structure that can be set for loudness processing or for “purist” processing, depending on the user-configurable crossover type (either allpass or phase-linear).
The 2300 can increase the density and loudness of the program material by two-band compression, limiting, and clipping. This improves the consistency of the station’s sound and increasing loudness and definition without producing unpleasant side effects.
The 2300 rides gain over an adjustable range of up to 25 dB, compressing dynamic range and compensating for both operator gain- riding errors and gain inconsistencies in automated systems.

Controllable

The 2300 can be remote-controlled by 5-12V pulses applied to eight programmable, optically isolated “general-purpose interface” (GPI) ports.
2300PC Remote software is a highly graphical application that runs under Windows 2000 and XP. It communicates with a given 2300 via TCP/IP over modem, direct serial, and Ethernet connections. You can configure PC Remote to switch between many 2300s via a convenient organizer that supports giving any 2300 an alias and grouping multiple 2300s into folders. Clicking a 2300’s icon causes PC Remote to connect to that 2300 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 2300 features (including advanced controls not available from the 2300’s front panel), 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.).
OPTIMOD-FM 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 2300’s GPI port or the 2300 PC Remote application), or by automation to permit broadcast system test and alignment or “proof of performance” tests.
OPTIMOD-FM contains a built-in line-up tone generator, facilitating quick and accurate level setting in any system.
OPTIMOD-FM's software can be upgraded by running Orban-supplied downloadable upgrade software on a PC. The upgrade can occur remotely through the 2300’s Ethernet port or serial port (connected to an external modem), or locally (by connecting a Microsoft Windows^® computer to the 2300’s serial port through the supplied null modem cable).