The ACAM 120 Acoustic Array has an acoustic camera, an array of 40 digital microphones. The microphones are sampled simultaneously with 24-bit resolution, providing accurate phase and amplitude measurements for beamforming and other digital signal processing algorithms.
Each microphone in the Acoustic Array has a useful frequency response from 50 Hz to 20 KHz. The microphones return useful information at frequencies up to about 24 KHz, with reduced accuracy. See Frequency Limits for the response limits for beamforming.
The sample rate is programmable: 51.2K, 32K, or 25.6K samples/second/microphone. Digital lowpass filters provide anti-aliasing.
The maximum sound pressure level for the ACAM 120 Acoustic Array is 114 dB.
An acoustic membrane protects each microphone from dust and moisture.
The ACAM 120 Acoustic Array has a 5M pixel optical camera located in the center of the array.
An on-board processor controls input and output while concurrently performing calculations. An on-board buffer memory of 256M bytes provides reliable gap-free data even at the maximum sample rate.
The on-board processor calculates FFTs continuously in real time for all microphones at the maximum sample rate, with a programmable block size from 64 to 2048 samples.
For synchronization with data acquisition systems the ACAM 120 acoustic array has isolated digital I/O: two inputs and two outputs.
The ACAM 120 Acoustic Array communicates with a PC through a USB 2.0 port. It requires just one USB cable for microphones, digital I/O, camera, and power.
With a fast PC the array returns gap-free time domain data and frequency domain data concurrently at the maximum sample rate of 50K samples/second/microphone.
The array is supplied with a 2m USB cable. It has been tested with the 2m cable and a 5m buffered extension cable.
The USB port provides all power for the array. The maximum current through the USB port is 500 mA.
The Acoustic Array has isolated sections for microphones and digital input/output. Microphone ground is connected through the USB port to PC ground.
Acoustic Array mounting hardware conforms to the 100 x 100 mm VESA standard. Wall mount, tripod, and desk mount adapters are readily available.
The ACAM 120 Acoustic Array weighs 3 kg. The shipping weight is 6 kg.
The ACAM 120 Acoustic Array operates at temperatures from 0 to 50 degrees C. It can be stored at temperatures from -20 degrees C to 65 degrees C.
The ACAM 120 Acoustic Array requires a 64-bit processor with Windows 8.1, Windows 10, or Windows 11.
The recommended processor is a 10th generation or higher Intel Core-i7 or equivalent with 8 Gb of DRAM. The recommended minimum is a 6th generation Intel Core-i5 processor or equivalent with 8 Gb of DRAM. Applications may run with reduced performance with slower processors and less memory.
Signal Interface Group recommends using solid state drives (SSDs). A 128 Gb SSD is adequate for most applications, but large raw data files require extra storage. Allow about 1G bytes for two minutes of raw data.