Low Noise, Low Distortion and Flat Response for Loudspeaker, Headphone and Microphone Measurement

Product Description

APx1701 Transducer Test Interface

The APx1701 Transducer Test Interface is an APx accessory device that integrates instrument-grade amplifiers and microphone power supplies for designers and production test engineers seeking clear insight into the behavior of their electro-acoustic devices.

Primarily designed for electro-acoustic testing, the system drives loudspeakers and headphones with dedicated power amplifiers, enables impedance measurements, and provides power to measurement microphones and microphones under test. Its functions are integrated with the APx500 audio measurement software and a connected APx analyzer.

It requires an APx500 Series analyzer and is supported by APx500 audio measurement software version 4.3 or later.


Power Ratings
100 W (1 channel into 8 Ω)
60 W (1 channel into 4 Ω)
30 Vrms (2 channels into ≥15 Ω)
Frequency Range
DC to 100 kHz
Frequency Response
±0.08 dB (10 Hz to 20 kHz, DC-coupled)
±0.30 dB (20 kHz to 50 kHz)
±0.80 dB (50 kHz to 100 kHz)
Voltage Gain
20.0 dB [x10]
Residual Noise
≤7.5 µVrms (22 kHz BW)
≤13 µVrms (80 kHz BW)
Signal-to-Noise Ratio
≈134 dB (ref 30 Vrms output)
Output Impedance
≈0.13 Ω (0.1 Ω current sense resistor in series with the – output terminal)
Residual THD+N
≤ –106 dB, 10 Hz to 20 kHz (80 kHz BW)



User Guide