Revolution in the world of the subwoofers

Sep 20, 2007 13:20 GMT  ·  By

Yep, I know this sounds completely wacko: after all, what could helicopters and subwoofers have in common? Well, I had no clue on such a rather weird relation between these two until I stepped onto the TRW-17 from Eminent Technology, which, by all means, is a subwoofer using a helicopter-type rotor.

It seems like this could be finally the answer to a question lasting for more than 50 years: how low can we go as far as sound reproduction through loudspeakers is concerned? Eminent Technology, with their newest (and most intriguing) contraption simply smile and answer: as low as you want; 1Hz would do?

Briefly, what's this great thing about? If you don't know how a helicopter rotor looks like, I'll just say it resembles a common fan but the blades can pitch, and thus being angled against the mass of air, generating more or less thrust. Well, this is what the TRW-17 does: we're dealing with a fan, rotating at a constant speed and having the pitch of its blades adjusted by the signal received from an amplifier.

Got that? Again, for those not so learned in the way of audio technology, I'll (again) add that the low-frequency sounds are generated by the moving cone of a bass driver oscillating a certain number of times per second. The woofer's cone is triggered by the electrical current (signal) coming from the amplifier; the bigger the woofer and the lower the frequency - the bigger the power generated by the amp must be.

Well, the TRW-17 from Eminent Technology has rid us of such problems, because the rotating fan is not powered up by the amplifier but by another (mains) current; the amp is just controlling the pitch, remember? Well, as the blades of the TRW-17 have a zero pitch there will be no sound... as they gradually change orientation they will produce sound at certain frequencies, dictated by the amp's signal and thus you'll enjoy a most serious bass.

Now, back to the hardware stuff, the TRW-17 must be professionally installed in either attic or basement, in an enclosed box, thus creating the "infinite baffle" and its sonic response channeled through transmission lines or similar openings in the walls or ceilings. Of course you can't actually hear a 5Hz bass and most likely nobody can... Nevertheless you can feel such infrasonic performance because this rumble exists around us in pretty many places, including in a helicopter's spinning rotor! Eminent Technology promise that the acoustic experience of an array with TRW-17 can't be compared with anything and you should listen to believe. Now, this might be true but in the end, let's take a look at what the TRW-17 actually means for your/your family's budget this year:

"Rotary Woofer Pricing:

-TRW-17 transducer $12,900.00 -Motor Controller $350.00 -Amplifier and crossover $700.00 -Design and installation, typical $8,000-$12,000* -Total $21,950-$25,950

*Note, design and installation fees include: 1. consulting engineering for the installation, 2. design and construction of the manifold at Eminent Technology 3. installation and setup of the TRW-17 by Eminent Technology 4. measurement and performance testing of the finished installation 5. travel for Eminent Technology employees 6. contractor fees for construction necessary for the installation." (Official price specs)

I guess I'll just wait for next year's spring sales...

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Photo Gallery (3 Images)

Yes, it's a scaled-down helicopter rotor-like thing
0-40Hz, easy as a breeze.The TRW-17 can generate sucha a strong airflow to open an unlocked door.
Open gallery