The acoustic performance of a traditional sound projector is fixed at the time the projector is designed. If this performance exceeds a customer’s specification, the projector will be heavier and larger than it needs to be. Furthermore, if this projector is part of a towed system, the tow body and its handling system must also be larger and stronger, all of which add to purchase and operating costs. On the other hand, if the performance of the projector does not meet the specification, one must either sacrifice a portion of the specification, or embark upon a time-consuming and costly redesign of the projector, if indeed a single projector can be made to meet the specification. With a Modular Projector System (MPS), you can have the sound projector you really want, no more and no less.

A MPS is assembled from a number of identical, flexural-disk sound projectors, commonly known as benders. Within wide limits, the number and spatial arrangement of benders determine the resonance frequency, bandwidth, power output, and cavitation depth. MPSs are a fraction of the size, weight, and cost of traditional sound projectors with equivalent performance. Furthermore, they are more reliable and easily maintainable.

The photograph above shows one example of a MPS that uses 24 benders in a single stack. It weighs 22 kg and has a source level of 208 dB re 1 mPa at 1 m at its resonance frequency of 380 Hz. We designed and built this MPS for a space-constrained application.

Another example is the free-flooding ring that is also manufactured by Ultra Electronics. The 24FA1000 shown in the photograph on the right is being unloaded from the transport boat to the DRDC-A calibration barge. The 24FA1000 can produce 100 kW of acoustic power and has no depth restrictions.