Multimode Audio Processor

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Also see model: 236 NOVIA AM Processor

The 223 is an audio processing powerhouse in a deceptively small package. Its versatile DSP-based design is user programmable to serve multiple broadcast applications - NRSC, AM, FM, SCA, TIS.

The 223´s parametric equalizer offers continuous control over the audio signal's frequency content with 3 bands of dynamic compression and selectable crossovers.

The unit addresses the needs of NRSC-compliant AM broadcasting with a range of cutoff frequencies, TIS (Traveler’s Information Service) advisories, monaural LPFM transmission, and analog SCA subcarriers. A full-range ‘Studio’ mode satisfies mic processing and general production needs.

The INOmini 223 features gated and windowed gain-riding AGC, 3 bands of adjustable dynamic range compression with selectable crossovers and variable EQ, and tight ‘lookahead’ peak control. Pre-emphasis, with its own protection limiting, and overshootcontrolled output filtering are individually and specifically tailored to the service selected.

"The INOmini 223 allows a station to reap the rewards of today’s digital technology thanks to this feature-rich, budget friendly processor."

Bill DeFelice -


  • Ideal for: STUDIO, US/NRSC AM, Worldwide AM, Shortwave, US/Euro Monaural FM, TIS, and analog SCA

  • Easy menu / jog-wheel setup from the front panel

  • Performs AGC, 3-Band Compression, Peak Control, and Output Filtering specific to the selected application

  • User-adjustable compression, EQ, limiting, and program density

  • DSP ‘lookahead’ limiting offers tight peak control without clipping

  • USB connector enables fast firmware updates in the field

  • Headphone jack


Why talk radio stations should be broadcasting in mono, not stereo.

- DAVID BIALIK. Radio World Guest Commentary, April 17, 2022 Let´s Talk About Mono

Inovonics Replaces 235 AM Processor With 223 Model

- Michael Balderston Model 223 processor comes in INOmini package

INOmini 223 Keeps It Simple

- Bill DeFelice - INOmini 223 Keeps It Simple


Operating Modes

  • NRSC-compliant asymmetrical AM processing with 10kHz, 9kHz, 7kHz, and 5kHz (9-pole Cauer)cutoffs
  • TIS asymmetrical AM processing with 5kHz (9-pole Cauer) cutoff
  • FM processing (monaural) with 75μs/50μs pre-emphasis and 15kHz (7-pole Cauer) cutoff.
  • SCA processing with smooth 5kHz (6th order Butterworth) cutoff

Frequency Response

20Hz – 20kHz, ±0.1dB in PROOF and Studio modes; all specialized applications conform to specified cutoff characteristics.


0.02% THD in PROOF mode.


Better than 72dB below the limited ceiling level measured through an appropriate de-emphasis network.

Program Line Input

Active-balanced (XLR) analog input, accepts nominal line levels between –20dBu and +20dBu.

Program Line Output

Active-balanced (XLR) delivers output levels between –15dBu and +12dBu corresponding to 100% modulation; 200-ohm resistive source. A switch under the top cover inserts a 20dB pad in the output for transmitters requiring a low level input.


3.5ms – 4.5ms, depending on selected application.

Headphone Jack

Front-panel (TRS) 3.5mm.

USB Port

Front-panel connection for firmware updates.


Input / Output / AGC Gain / Compression / Limiting


Flashing front-panel indication of audio loss and AGC out-of-range.

Power Requirement

12VDC at 200mA (2.1mm x 5.5mm coaxial); inline switchmode power supply included.

Mounting Options

An optional rack adapter mounts one, two, or three INOmini format units in a standard 19-inch, 1U rack space.

Size and Weight

1.6”H x 5.5”W x 5.5”D 4 lbs. shipping weight


Continuous operation at ambient temperatures between 32ºF/0ºC and 122ºF/50ºC; 0-95% relative humidity, non-condensing, altitudes to 10,000ft/3,048m.