Technical Information
iTestMic2 / USB-C
User Guide
Calibration Files

Second-generation iTestMic with iOS Device Charging and Audio Output

Now available for USB-C iPad, iOS, and other devices!


iTestMic2 is the only direct-connect iOS calibrated test & measurement microphone that includes a 3.5mm analog audio output and iOS device charging. Plug it into your iOS device for instant, accurate SPL readings, plug in a 3.5mm (1/8″) audio cable to get audio output signals, and plug in the included power adapter for long-term noise studies or just to charge your iOS device.

New! Now compatible with USBC iPads and iPhones, when used with the Apple Lightning to USBC Adapter.

Each iTestMic2 now includes individual frequency calibration files that improve the frequency resolution of the microphone and cancel out any minor capsule deviations.

iTestMic2 is the perfect companion for all iPhones, since it has an audio output and also allows simultaneous device charging.

See how to make an affordable and powerful hand-held audio analyzer system based on iTestMic2.

iTestMic2 has these features:

  • Plugs Directly into the Apple Lightning port
  • Direct-connect, bypasses all Apple analog electronics using a digital audio link and supplies charging power when the included AC adapter is plugged in.
  • On-board Analog Electronics
  • A high-resolution analog preamp, regulated low-noise power supply, Analog-Digital Converter (ADC), and Digital-Analog Converter (DAC) are used for precision measurements and audio quality.
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Factory Calibrated

Calibration is stored in the microphone for instant accurate SPL readings. Just plug iTestMic2 into your iOS device, launch AudioTools or another Studio Six Digital audio test app, and the calibration is automatically transferred to the app for accurate SPL readings. Since we use a regulated internal power supply, calibration will not change with varying iOS device voltage. No user calibration is required.

At any time, you may use a standard 1/2″ nominal calibrator and check or adjust the calibration.

Frequency Calibration Files

Every iTestMic2 is hand-calibrated during production at our US facility, comparing it to our Class 1 iPrecisionMic. The frequency calibration files are then downloaded directly into the app from our server.

Analog Output and Power Jack

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iTestMic2 includes a 3.5mm stereo analog audio output jack for test signals as well as general purpose audio output. Note that this is a full-level output and does not respond to iOS level controls.

Also on the bottom of the microphone is a 1.3mm 5.0VDC power jack input for iOS device charging. A universal voltage AC power adapter is included.

Professional Test & Measurement Microphone

TestMic2 1

The 1/2″ nominal diameter microphone has been designed to minimize high-frequency diffraction effects for the flattest frequency response.

iTestMic2 has 2 gain ranges to support a wide 25-120dBA SPL range.

The microphone capsule and electronics provide an extremely flat response,with low frequency response to 10Hz for accurate measurements below the audible audio range.

Using an Existing Lightning-Equipped iTestMic2 on a USB-C Device

Apple sells an adapter for Lightning accessories that allows full functionality on their USB-C devices, including all USB-C iPads and the new iPhone 15 and iPhone 15 Pro with USB-C. These devices support all features of our products, including automatic calibration, gain range changing, and device charging.

Check our this application note from Apple, or follow this link to purchase the adapter, which is priced at $29 USD. 


iTestMic2 has many uses, since it transforms any compatible iOS device into a professional sound level meter and sound analysis system.

  • Concert sound monitoring
  • Home theater audio tuning
  • Community noise studies
  • House of worship sound monitoring, system setup, and troubleshooting
  • Audiophile system analysis and correction

Now shipping!