Seas Excel Bifrost Kit - Pair - Parts only

Seas Excel Bifrost Kit- Pair, Parts only

$1,699.00

Seas Excel Bifrost Kit- Pair, Parts only

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Available Options:
Crossover Assembly:
Crossover Upgrades:
Optional Accessories:

For more information, please visit this products webpage.

This product was added to our catalog on Tuesday 10 November, 2009.

Quantity:

Seas Excel Bifrost Kit- Pair, Parts only

Drive units:

The woofer is the SEAS Excel W18NX001 . This driver has a paper cone that is treated on both sides. The front side of the cone is coated with Nextel paint to add some stiffness to the structure, while giving the driver an attractive appearance. The rear side of the cone is also damped with a special coating to further reduce cone resonances.

The voice coil is wound from copper-clad aluminium wire (CCAW) on a non-conductive glass-fiber former. The wire consists of an aluminum core that is covered with a thin layer of copper. The aluminum core reduces voice coil mass considerably, while the thin surface layer of copper allows for conductivity close to that of solid copper wire. The voice coil is generously overhung with a 20mm long winding height in a 6mm air-gap, providing long excursion with low distortion. Even with a large overhang, a correct voice coil rest position is important to ensure stable operation. This is verified using the Klippel Distortion Analyzer LSI measurement.

The Excel magnet system has been optimized for low distortion. The T-shaped pole piece has a small extension. This provides excellent symmetry not only in the actual air-gap, but also in the stray fields above and below the air-gap. There are two copper-rings in the magnet system, above and below the air gap. This reduces the voice coil inductance, and improves the inductance symmetry over the excursion range of the driver. The ring on the pole piece also prevents modulation of the magnetic field.

The Excel magnet system has been optimized for low distortion. The T-shaped pole piece has a small extension. This provides excellent symmetry not only in the actual air-gap, but also in the stray fields above and below the air-gap. There are two copper-rings in the magnet system, above and below the air gap. This reduces the voice coil inductance, and improves the inductance symmetry over the excursion range of the driver. The ring on the pole piece also prevents modulation of the magnetic field.

The tweeter is the Excel T29CF002 “Crescendo” . This is a new “state of the art” tweeter from SEAS. The patented Hexadym magnet system first used in the “Millennium” tweeter has been modified with more powerful neodymium magnets, resulting in a tweeter with very high sensitivity and low distortion. The open structure of the Hexadym system provides a free air-path from the sound radiated from the rear side of the dome through the short, but well damped hole in the pole piece. The rear chamber is filled with an absorbing felt pad.
The energy from the backside of the surround also radiates into a secondary chamber created by adding a small air volume between the top-plate and the sub-chassis. This volume is also damped using a foam insert.

Crossover Design:

The crossover was developed empirically, without confinement to the traditional textbook filter formulas. The drivers should be in phase at the crossover frequency, and the sum should be flat when both drivers are at –6 dB relative to the pass band level. Now the inevitable vertical off-axis cancellation, which is always present with the use of non-coincident drivers, is at least outside the listening axis (tweeter axis).

To accomplish this it was necessary to use a 2nd order electrical network in the high pass section and a 3^rd order network for the low pass. Both drivers should be connected with the same polarity.

Our Crossovers come with all necessary components as listed below. The components below are for our standard crossover version. If you wish to use more exotic components in your crossovers, please select the upgrade options in the pull down tabs at the bottom of this page. You will also see a option to have the crossovers assembled, or delivered in separate components.

The Standard Crossovers consist of Intertechnik 2mm Aircore Inductors which are the 2.7mh and 0.4(0.39mh) series inductors. The tweeter circuit incorporates a 1mh inductor and this is a 1.4mm Aircore Inductor. The tweeter series capacitor is a 3.9uf Jantzen Audio Superior Z Cap Capacitor and the woofer Capacitor is an Jantzen Audio Standard Z Cap 10uf Capacitor. Resistors are 10watt MOX. The crossover will be soldered and mounted on a 28cm x 14.5cm wooden board, glued and soldered with WBT Silver solder(if you request the crossovers to be assembled).

Upgraded crossovers include the following options:

Tweeter series capacitor is a 3.9uf AudynCap True Silver capacitors(+$190)

Tweeter series capacitor is a 3.9uf Jantzen Audio Silver capacitors(+$120)

Enclosure Design:

Cabinet drawings can be found on the pdf link below.

pdf Download Cabinet Drawings