MINIDSP EARS PRO Headphone Test Bench with ICP Microphone / Headphone Amplifier / USB DAC

The miniDSP EARS PRO is a professional test bench for headphones designed to perform precise and repeatable acoustic measurements for R&D applications, production quality control and calibrated binaural recording. It combines an adjustable stand with 1/2" pre-polarized measurement capsules, IEC 60318-4 compliant couplers, human-shaped soft silicone pinnae and individual calibration files for each microphone. Its 2x2 UAC2 USB audio interface integrates a 500MHz XMOS processor, an ICP microphone preamplifier with adjustable analog gain, a 32-bit ADC, a CS43131 DAC, an RCA analog output and a 6.35mm jack headphone amplifier. Connection to the computer is via USB-C, with support for Windows, macOS and Linux. The entire system operates with an external 12V power supply.

miniDSP EARS PRO: Adjustable Measurement Bench with Individual Calibration

The EARS PRO bench uses a 1/2" pre-polarized microphone capsule with a sensitivity of approximately 13.5mV/Pa, a frequency response of 10Hz to 20kHz and a BNC connector. The couplers comply with the IEC 60318-4 standard, and each microphone has a unique .txt calibration file referenced to its serial number, including frequency, amplitude and on-axis sensitivity drift data. The human-shaped silicone pinnae have a hardness of 35 Shore OO. The stand is made of aluminum with a heavy base designed to limit noise transmission. The headphone support offers 7 positions with an 8mm pitch, while the width adjustment between the ears offers 8 positions with a 9mm pitch and a fully adjustable width from 100 to 200mm. The plate also features 4 holes for mounting on a test bench and 3 additional holes for a mouth simulator, not included. The ear plate diameter is 120mm and the dimensions specified by miniDSP are 41.5 × 214.5 × 206 mm (H × W × D).

miniDSP EARS PRO: 2x2 USB Interface with ADC, DAC and Headphone Amplifier

The integrated audio interface uses a 500MHz multicore XMOS processor and operates in USB Audio Class 2 (UAC2), with support for 32-bit / 44.1 to 192kHz sampling rates and an ASIO driver for Windows; macOS and Linux are announced as Plug & Play. Its 32-bit ADC with integrated PGA provides up to 45dB of analog gain, adjustable via DIP switches from 0 to 45dB in 3dB increments. The input has an impedance of 30kΩ, accepts up to 4Vrms at 0dB gain and is rated at 140dB SPL, with a THD+N ratio of 108dB and a BNC input. The microphone preamplifier operates in ICP mode, with a 24V / 4mA IEPE bias at constant current. Digital-to-analog conversion is handled by a CS43131, with an unbalanced stereo RCA output up to 2Vrms, an output impedance of 100Ω, a THD+N of 110dB, an A-weighted SNR of 120dB and a response from 20Hz to 20kHz (±0.5dB). The headphone output on a 6.35mm jack delivers 125mW into 32Ω, with an A-weighted SNR of 118dB and a response from 20Hz to 20kHz (±0.5dB). The interface also features a USB-C port, an external 12V power supply and measures 31 × 160 × 90mm.