usbPrecisionMic is a USB-connected precision test and measurement microphone that meets ANSI and IEC electrical and acoustic Type 1 standards. It works with Windows PCs, Apple Macs, Android devices, and iPad (using the Camera Connection Kit).

usbPrecisionMic is factory calibrated to +/-0.1dB using a NIST traceable pressure-compensated calibrator. The calibration factor for both high and low ranges are recording on the factory calibration card in dBFS, so that application software can be calibrated to provide an absolute SPL level.

The usbPrecisionMic body is built of beautifully finished nickel-plated solid bronze tubing that is threaded to accept a standard 1/2” microphone capsule.

All of the active electronics are in the microphone body, including the microphone preamplifier using a 5 gigaOhm input impedance resistor, precision 24-bit A/D converter, and the logic circuitry required to communicate over a USB digital audio link. 

iPrecisionMic connects to the USB host device with a USB type A connector using a 1m (39”) cable. Included with usbPrecisionMic is a USB OTG (on-the-go) flat type A female to USB micro adapter, so that usbPrecisionMic may be connected to smartphones and tablets running the Android operating system.

usbPrecisionMic is now shipping from stock.


Loudspeaker Analysis — With its extremely flat and stable frequency response, usbPrecisionMic is the ultimate tool for loudspeaker setup and room analysis. Unlike typical plastic-diaphragm microphones, usbPrecisionMic does not any correction curve to be applied. Correction curves are only valid for one orientation, and at one SPL level. usbPrecisionMic provides flat response throughout its SPL range, and at a much wider incidence angle. It is also very stable over time and temperature, so its results can be trusted in all situations. Use usbPrecisionMic when the absolute best performance is required.

Live Concert Audio — usbPrecisionMic works with Smaart by Rational Acoustic, as well as other PC/Mac software, for applications such as live concert audio. Use usbPrecisionMic when the highest level of accuracy is required.

Noise Studies — usbPrecisionMic is also very useful for noise studies, given its low 18 dBA noise floor. Use it to identify noise sources, knowing that the results are reliable and can be used for reporting noise violations.

Android Apps — usbPrecisionMic works with any Android application that is able to select USB audio input. Later in 2015 Studio Six Digital will begin releasing audio analysis apps for Android that will be designed to work with usbPrecisionMic.

iOS Apps (iPad only) — usbPrecisionMic will also work with iPads when used with the Apple Camera Connection Kit.

Performance and Specifications

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A microphone is only as good as its capsule, and we use a special hand-selected thread-on capsule with a metal diaphragm built for us by ACO Pacific. Every microphone ships with its own calibration graph. 

usbPrecisionMic is very low noise, guaranteed to be below 18 dBA, for measuring room noise. It is also very flat, with a 3 dB rolloff below 3 Hz. The preamp self noise is typically 5 dB below the capsule noise floor.

usbPrecisionMic has two gain ranges. By default, it will start up in low range, which provides a typical usable range of 18 dBA to 110 dBA. Switching to high range provides a typical usable range of 35 dBA to 125 dBA. To switch gain ranges, issue USB volume up (for low range) or USB volume down (for low range).

iPrecisionMic has these specifications:

  • Response Characteristic Free Field response 0°
  • Omni-directional
  • Temperature Coefficient -10°C to 50°C, 0.01dB/°C
  • Influence of Humidity <+/-0.1dB (non-condensing)
  • Long Term Stability at 20° >250 years/dB
  • Dynamic Range (3% THD) 18 dBA - 125 dBA in two ranges controlled by USB volume commands
  • Frequency Response +/- 1dB 10 Hz - 20 kHz 
  • Fixed-USB Type A interconnect cable length 1m
  • Made in USA

Typical frequency response curve included with each microphone

Computer / USB Interface

usbPrecisionMic uses the built-in standard USB audio drivers on all platforms, so no installation is required before using it.

See the specification section above for more information about gain ranges. To switch gain ranges, issue USB volume up (for low range) or USB volume down (for low range).

Android Interface

usbPrecisionMic will work with most Android-based devices. To use with Android, follow these steps:

  • Make sure your audio application supports USB Audio Devices. Check with the App developer if you are not sure.
  • Update to the latest Android operating system. 
  • If you are not successful, try connecting through a powered USB hub. Not all Android devices are able to supply power to a USB audio device. Samsung S5 and S4 work fine, but Nexus did not in our tests, until we powered usbPrecisionMic with an external hub.


usbPrecisionMic is powered directly from the USB host device. It uses less than 60ma while audio is active, and much less when idle. 

It is not possible to supply power to the host device from usbPrecisionMic.

Type 1 Certification

At this time we do not provide Type 1 certification for usbPrecisionMic. If you connect usbPrecisionMic to a computer running that software that meets Type 1 specifications, you should be able to get the system certified as Type 1, since the usbPrecisionMic transducer and electronics are designed to meet those specifications.


We will have the following accessories available:

  • 20dB pad to allow extremely high SPL readings (148dBA)
  • Weatherproof windscreen
  • Weatherproof remote location mounting kit


usbPrecisionMic                  $1099.99

Now shipping from stock. Contact your distributor for details.