Infinity Epsilon

Beschrijving / Description

The Epsilon's bass chores are handled by a heavy-duty 12" driver with a 3-lb ceramic magnet, over-large (8") spider, 1.5" ong voice-coil, and greater-than 1" peak-to-peak excursion capability. The cone is composed of Injection Molded Graphite a combination of oriented graphite fibers and polypropylene which, according to Infinity, provides an optimum blend of strength, rigidity, mass, and damping.

This driver is mounted in a relatively small sealed enclosure. To get the desired extension and low-bass distortion, a servo feedback network is used. But while an amplifier is an integral part of most servo subwoofer designs (as in Velodyne, Genesis, Mirage, and earlier Infinity designs), the Epsilon requires separate woofer amplification. This is a mixed blessing, as we shall see.

The Epsilon system includes both a Servo Control Unit (SCU) and cables to link the SCU to a special input on the back of the speaker cabinet. This in turn is connected to an internal servo network which is linked to an accelerometer mounted at the apex of the woofer's cone. The accelerometer senses the motion of the cone, which is then compared with the amplifier output. If the two disagree, a correction signal is generated by the servo, which not only lowers bass distortion, but boosts the bass output to correct for the typical low-bass rolloff found in any real-world loudspeaker/cabinet configuration.

The system preamplifier's outputs are connected to the SCU inputs; outputs from the latter feed the amplifiers for the woofer and the top-end sections of each loudspeaker (see block diagram). The Epsilons must be bi-amped, therefore. The signal destined for the woofer amplifier is low-pass filtered and modified within the SCU, as called for by the Servo Control system. The full-range and unmodified top-end amplifier also passes through the SCU, but only as a hookup convenience. The crossovers for the upper-range drivers are passive, and located within the Epsilon's enclosure.

The upper-range drivers that take over from this Servo-Controlled woofer at 150Hz are similar in design to the EMITs (ElectroMagnetic Induction Tweeter) and EMIMs (ElectroMagnetic Induction Midrange) of past Infinity high-end designs. But both the drivers and their applications have undergone considerable refinement and modification. Their diaphragms are made of laminates of polyimide film, pressure-sensitive adhesive (with damping properties), and an etched, aluminum voice-coil (footnote 1). The EMIM and L-EMIM drivers are about 1.5 times the thickness of a human hair; those of the EMIT are less than half that. The EMIT also incorporates a specially developed fabric acoustic filter for smooth horizontal-dispersion characteristics.

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Infinity Epsilon

Beschrijving / Description

Specificaties / Specifications