In low frequencies a loudspeaker behaves like a high-pass filter by dampening low frequencies. The dampening characteristics will be a function of the mass, compliances (mechanical and acoustical suspension) as well as the resistance of the source (the amplifier).
In high frequencies, the deformations of the membranes will tend to create some resonance. In this system the masses in movement are parts of the mobile mass. The compliances will depend on the elasticity of the material and the resistances are the internal damping as well as the resistance of the source.
In order to achieve ideal damping in a wide area of frequencies, the impedance of the source must be a function of the frequency for each transducer.
The AOI system is made up of a system that detects the movement of the membrane and the coil as well as a filtered counter reaction. This is then tuned to achieve ideal dampening rate for each frequency.
The AOI system allows faithful sound reproduction with no transducer colouring in any frequency.
The advantage of PSI Audio’s AOI system is a greatly improved impulse behaviour compared to traditional amplifier designs.
Whilst the transducer travels to its intended position, the AOI circuitry seamlessly adapts the amplifiers output impedance to insure ideal acceleration of the membrane to reproduce the desired impulse.
Once the transducer reaches the end of the impulse, the AOI circuitry provides a break in order to prevent transducer overshooting.
The AOI circuitry can almost reproduce a perfect square acoustic wave and therefore increases the accuracy by integrating the transducer and the amplifier in to a single and perfect system.
A nice side effect of the AOI system is that the membranes of a PSI speaker do not produce parasite sounds when other speaker systems in the room are in use. When air pressure is produced by other sources, the AOI will detect this and tighten the damping of its transducers in order not to produce parasite sounds that don’t originate by the speaker system in use.
Nowadays reproduction of low frequencies has become very important. It is therefore essential to have a monitoring system with an accurate, and not simply flattering, reproduction of sound, especially when using sub woofer technology or in surround sound systems.
The result of the AOI featured PSI Audio speaker range is a speaker family with an extremely accurate impulse behaviour and with a minimum of transducer coloration.
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