Dayton Audio Omnimic 40K Precision Measurement Microphone System

Precision Made Simple, Redefining Acoustic Precision for Everyone

Dayton Audio’s OmniMic 40k is an essential tool for revealing the finest acoustic details. The robust device is engineered to deliver rapid and precise acoustic measurements essential for maximizing the performance of any audio system. Designed for professionals and hobbyists who demand perfection, the OmniMic 40k ensures that from initial acoustic measurement through to final system calibration, no detail goes unnoticed.

At the core of the OmniMic 40k lies our cutting-edge USB omnidirectional precision measurement microphone equipped with an integrated analog-to-digital converter. Boasting a compact 4mm capsule, the OmniMic 40k offers calibrated measurements ranging from 5Hz to an impressive 40,000Hz, comfortably enveloping the entire audible spectrum and beyond. The compact aperture minimizes internal reflections and edge diffraction, ensuring consistent response even when sound arrives significantly off-axis, thereby maintaining exceptional omnidirectional performance.

Featuring internal high voltage circuitry, the OmniMic 40k’s microphone offers an extremely wide dynamic range capable of capturing measurements up to 145 dB without suffering from compression or distortion. An easily accessible attenuator switch allows for level adjustments, ensuring outputs align seamlessly with the on-board ADC for maximum detail and precision. An exclusive addition is the IR receiver which, in conjunction with the PhotoLink, enables the system to precisely calculate both the time of flight and the distance between the acoustic source and the microphone. The sturdy stainless steel housing of the microphone further guarantees durability and sustained performance.

The innovative PhotoLink device sets the OmniMic 40k apart from competing measurement systems. Establishing an optical connection with the microphone, the PhotoLink enables exact calculation of time-of-flight and distance from the acoustic source to the mic capsule. This feature is crucial for accurate delay measurement and true phase capture, both essential for determining the Acoustic Origin Offset and creating precise on and off-axis simulations when designing any multi-way speaker system or array. The PhotoLink also features a visible 2.83V indicator to facilitate consistent signal level adjustment between measurements, essential for maintaining comparable sensitivity across different drivers. Remarkably, the PhotoLink operates passively, requiring no direct connection to the microphone or computer, thereby streamlining the setup process.

Easy to operate, the OmniMic 40k comes equipped with intuitive software that lets you start testing within minutes of unboxing. Every aspect of the sound from distortion up to 20,000 Hz to precise time of flight is easily accessible. Beyond functionality, its compact and portable design, coupled with an affordable price point, makes it an unrivaled choice in acoustic measurement.

Included are all the essentials: the OmniMic 40k microphone, PhotoLink, test leads, a 16.4 ft. USB cable, a compact microphone stand, a mic clip, and a wooden protective storage case, making it ready for immediate field use.

Trust in the Dayton Audio OmniMic 40k for a measurement experience that epitomizes accuracy, efficiency, and ease. Make it your go-to system to ensure your audio work resonates with clarity and depth, every time

For measurement up to 40,000 Hz, your system will need a digital-to-audio converter (DAC) with a sampling rate of 88.2kHz or higher and an amplifier capable of nearly flat response up to 40,000 Hz.

We recommend the following:

The Dayton Audio DAC01 USB interface provides superb digital-to-analog conversion in a perfectly portable package. With sampling rates up to 96 kHz/24-bit, this DAC is ideally suited for delivering clean output up to 40,000 Hz. Simple plug-and-play operation makes the Dayton Audio DAC01 USB audio DAC a perfect option for measurement systems.

Dayton Audio's versatile APA150 power amplifier delivers 75 watts per channel in its full-range stereo configuration, or 150 watts into 8 ohms when in bridge-mono mode. The compact size, flat response, and ample output power make this an excellent amplifier for acoustic measurement.

Frequency & Impulse Response

Frequency Response is a curve that shows how strongly an audio system reproduces different parts of the frequency range. A frequency response is related to its "impulse response" (the pressure signal that a speaker or sound system would make if it were fed by an extremely short pulse). Up to 40 saved Frequency Response curves (previously saved in "FRD" files) can be displayed on-screen simultaneously with the current measurement.

Polar Response

The purpose of a Polar Display is to reveal how the frequency response of a loudspeaker varies with horizontal or vertical angles from the baffle. Speaker designers generally design loudspeakers for a specified (usually, flat) frequency response at a position on-axis of a speaker and at some assumed distance from the baffle.

Harmonic Distortion

Harmonic distortion is the unwanted addition of new tones to the original audio signal. These distortion products occur at multiples of the original frequency and are centered on the harmonics of the original. For example, a 1kHz fundamental that has been subjected to harmonic distortion will produce energy at 2kHz (2nd harmonic), 3kHz (3rd harmonic), 4kHz (4th harmonic), and so on. OmniMic 40k will display 2nd thru 5th harmonics along with the total harmonic distortion.

Time of Flight and True Phase

When developing a speaker system, accurately identifying the acoustic center of each driver is critical to ensure that simulations align with real-world outcomes. The Photolink device establishes an optical link with the OmniMic 40k microphone, enabling precise measurements of both delay and distance between the acoustic source and the microphone. This integration streamlines the design and simulation process by eliminating any guesswork, or unnecessary steps.

Cumulative Spectral Decay

A waterfall (or CSD) illustrates, on a 3-D graph, how a speakers' energy decays or is radiated over a range of frequencies. Waterfall plots are used by driver and loudspeaker designers for driver selection, to identify resonances or reflections, and to view driver and waveguide behavior.

SPL Meter / Spectrum Analyzer

The SPL (Sound Pressure Level) meter is a tool designed to accurately quantify the loudness of a source. Additionally, the spectrum analyzer provides detailed insight, displaying the relative SPL across various frequency bands.

Energy Time Curve

The curve shown is the energy relative to the level of the energy in the first peak as an impulse comes from the speaker and reflects around the room. In other words, imagine the speaker sent out a sudden pulse rather than the sweep this test uses.

Oscilloscope

Leverage the Oscilloscope to effectively visualize sound waveforms encompassing musical tunes, vocalizations, or emissions from loudspeakers. This tool offers precise insights into the dynamics and details of audio signals.

Bass Decay

Utilize the Bass Decay Analyzer to accurately gauge the decay of bass notes within a given space. This measurement is essential for comprehensively understanding and compensating for the influence of the room's acoustics on the lower frequencies.

A unique serialized calibration .txt file will be available for your OmniMic 40k . Once you receive your microphone, Visit where you will be prompted to enter the serial number found on the base of your calibrated OmniMic 40k. After entering the serial number, your unique calibration .txt file will be available for you to download.

The OmniMic 40k's test signals will be initiated directly from the host computer. However, in some cases you may need a source already integrated into an existing system. In those cases we offer the following:

For use with existing audio systems, the allows you to play the signals from any CD player. Up to 20,000 Hz only.

For use with home theater surround sound systems, the makes it easy to test each channel in a 5.1 setup. Up to 20,000 Hz only.

Note: Windows 10 and 11 Users
Microsoft .net Framework 3.5 is required for the Omnimic software to run properly. This is not installed by default in Windows 10 or 11.