Genesis Advanced Technologies S4/8 owner manual The Technology, a b s o l u t e f i d e l i t y

a b s o l u t e f i d e l i t y ™

The Technology

The Servo Advantage

Very few loudspeakers use servo drive, either because most designers think that it is too difficult to design, too expensive, or because of the extraordinary demands a servo system makes on the amplifier and the transducer. However, the Chief Scientist of Genesis, Arnie Nudell, first introduced the servo system in the legendary Infinity Servo Statik One in 1968(!) – so we know how to design and build servo systems.

The concept of our servo bass system is an easy one to understand: It employs an accelerometer as a sensor to constantly monitor the movement of the woofer cone, and instantaneously compares it to the input signal. This comparison circuit identifies any deviation from the ideal and instantaneously applies a corrective signal to compensate for the deviation; virtualy eliminating inherent woofer distortion.

As an example, when you have a high-impact, low-bass signal that starts and stops suddenly (for example a kick drum), the inertia of the woofer cone causes the cone to be slow to begin moving. Once the cone is in motion, the momentum of the cone causes it to keep moving - even after the output signal of the amplifier has stopped.

The sonic result is overhang, bloat, lack of tautness and definition, and a blurring of dynamic impact. With the servo system, the circuit senses that the woofer is not moving as fast as it should, and applies more current to make it move faster. When the signal stops, it detects that the woofer is still moving when it shouldn’t, and applies a counter- signal to cause the the woofer to stop faster and more effectively than normal circuitry would.

Thus, the servo-drive reduces distortion and improves transient response by making the woofer seem mass-less. Typical non-servo woofer systems have distortion levels that exceed 10% at even moderate levels. The Genesis servo bass system reduces this distortion to below one percent at almost any output level. Moreover, it drives the woofer to constant acceleration, which makes its frequency response nearly flat!

500W Class-D Switching Amplifier

The servo system places extraordinary demands on the amplifier because it uses enormous amounts of current to make the woofer follow the signal. This means that the amplifier used must deliver huge amounts of clean power.

S4/8 Owners Manual Ver 0.1

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