The two major features differentiating the new OmniMic from its predecessor include an expanded high-frequency range by an octave from 20kHz to 40kHz and a new PhotoLink delay measurement system. Using the new OmniMic software version 6, out of the box OmniMic 40k measures like the original OmniMic V2 out to 20kHz. However, the new OmniMic 40k can measure out to 40kHz by using a USB 24-bit/96kHz DAC such as the Dayton DAC01 ($39.95) and playing Flac or Wav files for the stimulus played through a 96ksps file player. Doing this allows SPL measurements to 40kHz, second-harmonic distortion to 20kHz and third-harmonic distortion to 13.3kHz.
Not only does the new OmniMic measurement microphone measure to 40kHz, it also has a 145dB dynamic range, which in its price range ($599, not including the DAC) is unheard of. To facilitate very high SPL measurements, this measurement microphone includes a -24dB attenuation switch (Photo 3) to prevent overloading of peripheral devices.
The PhotoLink system (Photo 4) is the IR receiver built into the microphone which, in conjunction with the PhotoLink box, enables the system to precisely calculate both the time of flight and the distance between the acoustic source and the microphone. In use, the PhotoLink box is located near the acoustic source and connects with a set of alligator clips across of amplifier output or loudspeaker input.
The graphic output of OmniMic 40k now includes frequency and impulse response, polar response (Figure 1), harmonic distortion (including new user selectable markers shown in Figure 2), cumulative spectral decay (CSD), SPL meter/Spectrum analyzer, Energy Time Curve (ETC), an oscilloscope, Bass Decay, and loudspeaker power compression (Figure 3). There is an online 87-page manual available online, which details all the numerous enhancements to the new OmniMic 40k system.
The second new measurement tool is the DATS LA (Photos 4-6), which is an entirely new loudspeaker measurement product from Dayton Audio. The new analyzer uses a patented DC offset bias technique to derive both small and large signal parameters, including both linear and nonlinear output capability.
This compact, computer-controlled system features a powerful 100W AC/DC amplifier allowing quick and easy small and large signal parameter testing. Its patented symmetry test method uses multiple DC-biased sweeps to analyze nonlinearity and asymmetry driver characteristics - US Patent #11,272,301. With precise DC bias control and proprietary data processing, DATS LA offers insights into driver performance, making it a valuable tool for transducer analysis and development.
The new DATS LA offers a cost-effective hardware and software suite priced at $499.98, and is capable of evaluating both linear and nonlinear aspects of loudspeakers. Its uses a patented technique for measuring loudspeaker nonlinearity and asymmetry through multiple DC biased sweeps. And by precisely controlling the DC bias and employing a unique data processing method, DATS LA provides insightful data for optimizing loudspeaker motors and suspensions.
A robust 100W AC/DC amplifier facilitates precise measurement of drivers’ small or large signal parameters under varying input levels. The device connects to any PC via USB port, with advanced short circuit protection to protect amplifiers. For professionals and hobbyists, it can help design and optimize loudspeaker drivers and systems.
More than that, the new analyzer allows measuring parameters using small (low power) or large (high power) signal analysis. Apart from the mentioned patented DC biased measurements, the analyzer offers measurement of advanced Wright Model coefficients (Kr, Xr, Ki, Xi) for impedance simulations.
A software signal generator with selectable waveform, frequency, and amplitude is built-in, while the DATS LA also functions as a highly accurate LCR meter, allowing precise measurement of:
• Resistance (Re): 0.002Ω to 10kΩ.
• Inductance (L): 0.05mH to 100mH (with DC resistance).
• Capacitance (C): 0.002μF to 10,000μF (with ESR, dissipation factor, and Q).
There is even an oscilloscope software mode with dual traces, plus adjustable time and amplitude scales.
The graphic output for the DATS LA can be seen in Figures 4-9 and include small signal Thiele-Small parameter (TSP), large signal TSP, Bl vs. Excursion, Kms vs. Excursion, Le vs. Excursion, and Excursion per Volt. (The Excursion per Volt graph presented effectively illustrates the relative excursion as a function of input voltage, enabling the easy observation of the onset of compression characterized by motor force reduction and stiffer suspension.)
The new DATS LA is a fairly complex instrument, so you can read the online 85-page manual as well as watch a number of YouTube videos posted by Dayton Audio on both the Dayton Audio website at www.daytonaudio.com, or the Parts Express website at www.parts-express.com. VC
This article was originally published in Voice Coil, June 2025.
