The is a 5.1 system. 3 identical S-100b's, pai of SS150thx and MX150 THX sub. All hardly used as seen by the dust.:)
The introduction of a three-tweeter phased array, (S-100B) coupled with the unique Phase-Focused crossover, set a precedent in the industry for accuracy, clarity, focus, and dynamic range. The three tweeter array gives tremendous added acoustic headroom necessary for accurate transients, while the phase focusing ensures the three tweeters and the two 5-1/4" drivers present a single, coherent, unified musical source to the listener
MK Sound SS-150 THX Black Tripole Surround Speaker - SS150BK/ 25 - 200 Watts Recommended Power/ 4 Ohm Impedance/ Phase-Focused Crossover/ 5-1/4" Woofer Driver/ 1" Soft-Dome Tweeter/ Two 3.25" Polypropylene Cone Mid Tweeters/ Black
MX-150THX's Deep Bass sealed-box design produces significant deep bass output down, with an in-room response flat to frequencies well below 20 Hz. Many other THX subwoofers have vented cabinets, giving them an extremely sharp rolloff below the lower limit of their "flat" response. By reproducing bass frequencies lower than 20 Hz, the MX-150THX has a lifelike power and authority that these other subwoofers cannot match. M&K's Push-Pull Dual Driver Configuration delivers a major improvement in bass detail and articulation by virtually eliminating even-order harmonic distortion and doubling the sound power per watt of amplifier power, for 6 dB of additional output!
NEW, HIGH-PERFORMANCE MAGNETICALLY SHIELDED DRIVER
The MX-150THX's new, long-throw 12" magnetically shielded driver is capable of significant output levels to below 20 Hz, and it does not require the subwoofer to be placed two to three feet away from the television!