Seas Thor Speaker Kit
INSTRUCTIONS PDF
Premium MTM design using Seas Excel drivers in a transmission line cabinet. Transmission-line (TL) loudspeakers have long enjoyed a small but dedicated following, especially in the DIY community. The advantages of TLs are well known. They are essentially non-resonant enclosures, producing a deep, well-controlled bass response. For a given driver, bass response can often extend well below that produced with either a vented or sealed enclosure using the same driver. Above a few hundred Hz, the line-filling material completely absorbs the driver back wave, giving the TL an open, non-boxy sound.
The Seas Thor kit consists of 4x Seas W18E-001 7" woofers, 2x Seas T25CF-002 in MTM arrangement, 2x fully assembled premium crossovers, and all internal accessories required. The two W18 Excel magnesium cone woofers and the T25 Millennium fabric dome tweeter are mounted in a D'Appolito configuration. The D'Appolito configuration offers a number of advantages over standard single-woofer designs:
* Controlled vertical directivity in the midrange which reduces the effect of floor and ceiling reflections.
* Excellent imaging and spatial characteristics.
* Higher system sensitivity.
* Lower distortion.
* Increased bass output.
The kit includes a detailed PDF printout with instructions for assembly, including easy-to-read cabinet plans and installation of the accessories.
For more in-depth information about the design, please see the article by Dr. Joseph D'Appolito and Dennis Colin in AudioXpress.
Specifications:
Configuration:
The THOR is the top-of-the-line loudspeaker kit from SEAS. It is a full range, floor-standing system that provides the very highest level of acoustic performance. The enclosure uses a transmission line configuration, derived both from sophisticated computer modeling and extensive experimentation. The line is tapered, and filled with Dacron stuffing. The two W18E001 woofers excite the line at slightly different points, smoothing the response and increasing the range of bass output. The transmission line produces 4 dB of bass lift from 20Hz to 110HZ, with less than 1 dB of ripple. The -3dB point is 45Hz, with roll off of 12dB per octave below 45Hz. Usable in-room bass response extends well into the low 30Hz range.
Crossover details:
The crossover network is conventional except for a parallel circuit which suppresses the response peak due to the magnesium cone. The crossover frequency is 2.5kHz. We are building these exclusively with high-end parts: Goertz Copper Foil inductors, Clarity CSA capacitors, and Mundorf resistors(Please note the older-style ESA caps are pictured).
Upgrade further to Mundorf Supreme on the hi-pass via the pull-down menu.
Optional Accessories Package:
4x Bennic DB Single-Wire Terminal Cups
18' Foam Tape for gasketing
24 oz. of Poly Fill
32x #8 x1" Pan Head Screws
12x #6x 3/4" Pan Head Screws
16x #6x 3/4" Oval Head Screws
34' Supra Classic 1.6 cable
36" Solder
1 tube GOOP
Online reviews of the Seas Thor Speaker Kit
Single kits may be ordered for half the pair price.