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Legacy Foundation Subwoofer Preview



  • Product Name: Foundation Subwoofer
  • Manufacturer: Legacy Audio
  • Review Date: March 14, 2017 07:00
  • MSRP: $3850
  • First Impression: Gotta Have It!

  • Design: Dual Active Driver, Dual Passive Radiator System
  • Driver Specifications: (2) 12" spun aluminum diaphragm, 480oz motor structure, cast frame, 3" dual 4 layer voice coil, 2" peak to peak travel
  • Passive Radiator Specifications: (2) 12" Patented Symmetrically Loaded Passive System radiators, 4" peak to peak travel
  • Amplifier: 1000 Watts Class D ICEpower
  • Frequency Response: 16 Hz - 120 Hz (+/-2dB)
  • Impedance: 10k Ohms
  • Inputs: 2 x RCA, Balanced XLR, LFE
  • Phase Adjustment: +/- 180 degrees continuous
  • Blend EQ: +/- 12 dB @ 45 Hz
  • Low Pass Filter Slope: 18 dB per octave
  • Low Pass Crossover Frequency: 40 Hz - 120 Hz
  • Low Frequency Alignment: Electrically Assisted 6th Order
  • Weight: 113 lbs
  • Dimensions (DxWxH): 15” x 14.5” x 29”

In building construction, the foundation is where the structure anchors its weight to the earth thereby supporting everything built on top of it. Bass frequencies can be considered an analogy for the foundation of sound since lower frequencies are the fundamentals on which the harmonics are built and so carry the weight of the sound. For music, it is said that the bassline is the foundation on which the melody rides. This being the case, Legacy Audio’s choice to name their new subwoofer the ‘Foundation’ is very appropriate. In construction, as with sound and music, the foundation must be strong enough to carry the weight of the superstructure above it, and with the ‘Foundation’ subwoofer, Legacy has ensured a very strong footing indeed.

Legacy 12

Legacy 12" Foundation Subwoofer Driver

The Foundation subwoofer is dual driver, dual passive radiator design powered by a thousand-watt ICEpower amplifier. Two long-throw 12” woofers are coupled with two extremely long-throw 12” passive radiators, and all of that adds up to a great deal of displacement. The active driver’s 2” peak-to-peak travel is exceptional excursion for a 12” woofer, but the passive radiator’s 4” peak-to-peak travel is extraordinary. The throw of the passive radiators is so long because normally twice as much displacement is needed for the radiators as that of the driver, to prevent over-excursion of the radiators. The Foundation is not a huge subwoofer, so to really move these long-throw radiators in a small volumetric enclosure a lot of motor strength is needed, and that comes in the form of an enormous 30 lb. motor structure for each driver. Doubtlessly that weight is largely composed of magnet and provides the massive amount of flux needed for a powerful grip on the cone to keep the woofer well-damped (particularly for an electrically low Q). 3” dual voice-coils set the stage for a powerful electromagnetic field, with leads woven into the spider so they do not slap the cone on large excursions. 

Foundation_Rear_Terminal_revisedC.jpg      Foundation_Sub_rear_top_view.jpg

Legacy claims a 16 Hz to 120 Hz response within a +/- 2 dB window for the Foundation, making it a very capable subwoofer for the most demanding movie soundtracks. One unusual feature on the Foundation is the ‘Blend EQ’ control, which can boost or lower the band centered around 45 Hz by 12 dB. This is like an EQ at a fixed frequency and Legacy chose this frequency to “match the first cancellation node of most rooms”, in their words. Development of the Foundation went through sealed designs, multiple flared ports, a combination of flared ports and slot-loaded ports, but ultimately Legacy settled on the passive radiators to achieve powerful deep bass without the penalties of port noise from vented designs. Legacy Audio’s president and loudspeaker engineer Bill Dudleston says of the Foundation subwoofer: “The sense of pitch audibly truer than any sub I've designed to date.”  

Crack the Foundation

One of the biggest selling points of the Foundation is the amount of power available in such a small footprint: 1.5 square feet. This makes it a great choice for situations where a lot of bass power is needed in rooms where floor space is at a premium. Its availability in an array of select veneers allows the Foundation to fit in virtually any decor. Of course, a powerful subwoofer in a relatively compact package in a high-end finish comes at a considerable price: introductory MSRP at $3,850 in standard finishes. The Foundation is not inexpensive but among the subwoofers that ticks the checkboxes of powerful, luxury-finish, and small-footprint, it looks to be very reasonably priced.

The aptly-named 'Foundation' subwoofer can serve as a bedrock for your sound system, but so much power in such a small package should come with a warning that if it is pushed hard enough, it may create cracks in the foundation of any structure it is used in. Proceed with caution!

Unless otherwise indicated, this is a preview article for the featured product. A formal review may or may not follow in the future.

About the author:
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James Larson is Audioholics' primary loudspeaker and subwoofer reviewer on account of his deep knowledge of loudspeaker functioning and performance and also his overall enthusiasm toward moving the state of audio science forward.

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