Marschall Acoustics Instruments Pty Ltd

Marschall Acoustics Group
Marschall Acoustics®

Bespoke Geophysical & Audio Domain Solutions







Analog electronics typical of front-ends shown.

Useful in long low frequency solid seismic cables.

Power Module

Superior array fidelity requires clean power. Each hydrophone group of the MAI Trout array has its own precision regulated bipolar power supply. This prevents noise on the main array power lines from reaching the sensitive signal conditioning electronics while helping to isolate groups from each other.

Extremely low noise and distortion.  Among the best in the world at any price.


MAI's ultra low noise preamplifier accepts up to 4 hydrophone (or other sensor) branches in single-ended or true-differential mode. Driven calibration inputs are also provided. Gain is set by a single resistor during assembly. Low cut and high cut filtering are standard, as is pseudo-differential output.

Affords great flexibility in group design, group shading, and pre-emphasis.

Summing Network/Line Driver

The summing network/line driver circuit board designed by MAI accommodates up to 8 channels (differential) or 16 channels (single-ended), separately weighted inputs. A wide variety of filtering and prewhitening is available by the selection of a few components. Outputs are true-differential and capable of driving twisted pair data bearers in excess of one kilometre with negligible distortion. The use of this flexible module makes the provision of overlapping shaded groups in geophysical arrays straightforward.

Need to distribute high quality signals around your towing vessel ?  This is the board for you!

Geophysical Receiver Boards

MAI's geophysical array receiver boards provide a host of features:

  • true differential inputs with better than 100dB
    of common mode rejection;

  • full overvoltage and spike protection;

  • adjustable and DC switchable gains;

  • filtering and signal conditioning; and

  • true differential output.

Test and Inspection

Shown here undergoing test and inspection after a burn-in period on the electronics lab test bench, twenty-four channels of geophysical receiver boards draw less than 400 mA per side from a bipolar power supply.

Not exactly low power, but not a "pig" either!

Next, really low overhead manufacturing.