Hybrid Acoustic Filters

Hybrid Acoustic Filters are simple low pass acoustic filters that directly fit over the front of drivers or are constructed as an integral part of the driver basket or speaker enclosure. Patents are pending.

Fundamentally hybrid acoustic filters have 2 main functions:

• Reducing distortion
• Controlling polar pattern

The hybrid acoustic filters remove distortion components from the whole signal path including source material, pre-amp decoding and signal processing, amplifier and  loudspeaker all of which can introduce unwanted harmonics.

Direct radiating loudspeakers are inherently distorted even with motional feedback because there is nothing in place to clean up driver mechanical or air noise. Hybrid driver acoustic filters are a low cost solution that come after the loudspeaker cone. Properly designed they can be tuned to filter out harmonics coming through the system, harmonics produced by the driver and mechanical or air noises produced by the driver.

Proper design of the acoustic filter involves the inter-related issues of choosing an appropriate frequency band, tuning the filter and at the same time creating an optimal polar response.

Ideally a loudspeaker system should have consistent polar response. In other words, the frequency response and SPL should not vary over the typical angles at which an audience may be seated. Hybrid acoustic filters provide an effective solution to inconsistent polar patterns and substantially reduce the frequency range where beaming may occur.

The filters can be used effectively in single drivers, coaxial drivers and split systems.

Advantages of hybrid acoustic filters

• Reduces distortion
• Controls polar pattern
• Protects driver from damage
• Hides driver in case of in-wall installations
• Low cost construction
• Suitable as a modular component