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BBC's Super Senses

Infrasonic interaction with Elephants

Provoking a mating dance from an alligator


The Polynesian Cultural Center

Technifex uses rotary woofers to replicate earthquake sounds


Sound Source Research and Development

Special infrasound sources using rotary woofers


Can your subwoofer be measured at 3 Miles???

Milton Garces Measuring a TRW-17 outdoors


Evergreen Aviation uses a rotary woofer in its Titan Missile Exhibit

Evergreen Rotary Woofer Installation


Cameron Carpenter and Telarc use rotary woofers in Camerons -Revolutionary- recording

Cameron Carpenter and Telarc


The TRW-17 appears in the 2008 issue of the Guinness Book of World Records


Technifex chooses 6 TRW-17 rotary woofers for installation in a Niagara Falls Welcome Center project

Details about the Niagara Falls Rotary Woofer Installation


PBS Television Show Wired Science features

Milton Garces Infrasound Research Laboratory


Florin Tibu, Audio Editor article about the Rotary Woofer in



Machine Design Magazine puts the TRW-17 on the cover!


Read Tom Nousianes comments about the Rotary Woofer in

Sound and Vision


See the First Full Review in IAR by Peter Moncrieff!

The Only Subwoofer


Janine Elliot writes about the TRW-17 in Hi-Fi News and Record review January 2007 issue


California Twin Rotary Woofer Installation Page

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Want to hear what 5Hz sounds like? A new woofer technology unlike any other and a new product category for home audio. This is the first home audio woofer delivering true response to DC. The Thigpen Rotary Woofer is the worlds first true infrasonic home audio or home theater woofer. Conventional subwoofers roll off rapidly below 20Hz. With no cone the rotary woofer achieves high efficiency at very low frequencies. Most subwoofers have a difficult time producing acoustic output below 20Hz at audible levels. They generally require large amounts of equalization, distortion rises rapidly, and even the most expensive available cannot produce significant output below 10Hz. Subwoofer electronics usually contain a cutoff filter which sharply rolls off content to the subwoofer below 20Hz to protect the speaker. On the other hand, the rotary woofer has enough acoustic output to move an open door back and forth 0.5" between 1 and 5Hz! It has enough output to find resonance frequencies of walls and ceilings in a room. It requires no equalization to achieve flat response to below 1Hz. Microphones have low frequency capability that far exceeds the low frequency output of current subwoofers. In many cases infrasonic information is in a recording, it is not being reproduced by the sound system.

A missing link in sound reproduction. Experience special effects like never before. If you want to hear and feel the 11hz hertz fundamental frequency from a helicopter rotor, the low frequency rumble of wind, the space of a concert hall or infrasonic information contained in an explosion, this is the only woofer technology available. Over the years the generally accepted low frequency limit of hearing has been 20Hz, some suggesting 16Hz. However nothing existed to produce significant enough output to change this belief. This development will spawn new special effects and we will begin to understand the true low frequency limit of human hearing. The TRW-17 rotary woofer is now being used in theme park attractions, concert venues, professional audio applications and research projects.


  • Amplifier Requirement: 150 watts @ 8 ohms
  • Impedance: 8 ohms 0Hz : 0Hz
  • Frequency Response: 1Hz : 30Hz ± 4dB
  • Suggested Crossover: 20Hz @ 18dB/octave
  • Sensitivity 94dB 1 watt 1 meter @10Hz
  • Maximum Acoustic Output: >115dB between 1 and 20Hz.
  • Distortion: Typically 3% or less between 1 and 20Hz @90dB
  • Warranty : 3 years parts and labor

Measured Frequency Response

Typical Installation

Note, for home audio the model 17 must be professionally installed in an attic, basement or side room which becomes an infinite baffle. We have developed an amplifier and crossover solution unique to this product. See pricing for more information. If you wish to use your own electronics, the crossover/amplifier should be capable of operating near its rated power at between 1 and 3 Hz.

TRW-17 Front View

TRW-17 Side View