The minimum power of a subwoofer that could make 18-20 Hz frequency really audible or clearly felt.?

Question

Examples of such subwoofers would be highly appreciated.

Answer 1

This is kind of a tricky question.

Some good subwoofers only have 200-300 watt amps. But the driver is a HUGE 18" driver.  

Many wives do not want a water-heater sized box in the room, so some subs are designed with a 12" or 15" driver, but to get low frequency they need to move (and stop) the cone so the amps are in the 1,000 watt range.

Some companies make subs with 8" drivers and put 2,000 watt amps in them.

So it is a range.

And keep in mind that the amp serves 2 purposes:

- To start the driver moving

- To stop the driver moving

Go to the SVS website. These guys used to help people design and build their own subs so they put a lot of good techincal information on their site.

They do have subs that will go down to 14 hz - but they only recommend these for people with a love of pipe-organ music.

Answer 2

First the few basics-

Human hearing capacity starts from 20Hz and goes upto 20KHz (usually in children). Most of the people have hearing range less than this and with age, this diminishes further.

Subwoofers that go to this low or below, usually produce effect by clearly getting the harmonics (the higher frequency relatives of the low tone) right.

Very few musical instruments go this low and when they do it's just once or twice in a whole musical piece (eg- C3 32.7Hz on double bass, Contrabasson - 29Hz, Bass Trombone - G Flat4 23Hz, Grand Piano - 27.5 Hz A4)  

Most of the 'felt' bass is also called the higher and mid bass and comes in the range of 75Hz to 200 Hz.

The lowest frequency your room can produce is also limited by the dimension. You can calculate it by 565/Longest dimension of your room in Feet. (Try to find out where I got this number from)

Now coming to answer your question. I am just going to give an example of the power required by quoting from an article published in Stereophile of 1986.

Kick Drum: Produces a broad span of frequencies with very high energy between 30 and 80 Hz. (Live levels can reach 127 dB, equivalent to 25 acoustic watts, or a typical box loudspeaker being driven by a 3000 Watts Amplifier)

This 3KW quoted here is RMS value and not the peak !!!

I have a respectable sized room and I personally use a Quad sub for home theatre. I use just two channels for stereo on a different system.

Some subs you can try out after getting the above facts clearly understood -

Quad L- Subwoofer

REL Stadium III

B & W PV1

Monitor Audio RS W12

Answer 3

Power is important, but subwoofer driver efficiency is equally as important as well.  If the woofer is not efficient, you will need a whole lot of power to get the desired loudness (i.e. bass impact).  Here are some powered subwoofer brands to consider to meet or exceed your criteria...

- Hsu Research VTF-2 Mk3 or higher

- SVS

- Definitive Technology

- Dayton Audio Titanic 12" or 15" models

Happy ground shaking!