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This is the Quadripole Subwoofer System.

The Quadripole Subwoofer System has power and SLAM! 

It consists of 4 cabinets, 2 pairs per channel. It is unique in its construction, as far as I am
aware there are no other subwoofer systems like this one. The Quadripole is capable of extremely
intense low frequency output. Today, there are new modern design drivers that have extraordinary
excursion (Xmax) and power handling capabilities, coupled with very low Fs (low frequency rolloff)
that make it possible to improve upon this already impressive design. (see below for a link)
Please click on this 
thumbnail for a large
view of the 

The Quadripole is a unique design in several regards.

First, it is configured to permit the placement of speakers on top of the subwoofer cabinets (as illustrated).
This permits a nearly ideal relationship between the main speaker(s) and the Quadripole. It is always better from
a time/phase point of view to have the subwoofers in front of the main speakers. The usual rear or corner
placement is a compromise for this reason (and several others as well).

Second, the Quadripole is relatively room insensitive as compared to other subwoofer designs. Actually, it is
sounds virtually identical regardless of the room it is placed in, or the room placement. This can not be said
to be true for most other subwoofers. Those subwoofers that suggest a rear wall or (worse) a corner placement
do so for two reasons: 1) to augment output and 2) to augment low frequency response. The problem with
this idea alone is that the subwoofer is now entirely dependent upon the room for its character and response!
The same subwoofer will sound different depending upon placement and the physical characteristics of the
room itself.

By comparison the Quadripole is designed to NOT require a boundary in order to produce bass and very low bass.
To the contrary, the Quadripole is intended to be placed away from the walls, and where your speakers
are placed.  Tests in rooms of dramatically different shape, design and materials (wood floors vs concrete,
low vs. high ceilings, etc...) have been done which show that the Quadripole is truly outstanding in as much
as it does not react to the room significantly. (some room interaction at low frequencies is inevitable...)

The Quadripole puts SUB-BASS into the AIR, not into the walls and floors.

Design & Specs

The Quadripole uses two active 12" extra large Xmax high power drivers per channel - if you click on
the link you can see the actual drivers, and the curves of the in room response. This permits each channel
to be set for a 4 ohm impedance (others available on request). Not seen by eye are the dual planar 18" passive
radiators, built by BEAR Labs. There are 4 per system! One of the 'secrets' of the high performance of
this subwoofer system are the Passive Radiators, which outperform any commercial PR we have ever seen,
bar none. Each channel is driven with a high powered, high damping factor amplifier. BEAR Labs suggests
the use of a Crown Macro Reference, although other amps can be utilized (please consult with us). The
Quadripoles are crossed over using an active Low Pass filter section. I do not recommend an active High Pass
filter for most applications.

The original intent was to mate with ESL speakers. So, the Quadripole was intended to mate seamlessly by
taking advantage of the natural LF rolloff found in most ESLs. The crossover was originally configured
this way, and rolled off the response between 65 and 100 Hz., extending to an F3 of 21 Hz. A true
Sub Woofer!

Today, with the advent of certain full range ribbons, and high quality midbass drivers ("mini-monitors")
it is desirable in some cases to meet the main system as high as 300 Hz. The new drivers used in the
Quadripoles are smooth and clear up to 500 Hz., so it is without any reservation easy enough to configure
the electronic crossover for any point between 50 Hz. and 300 Hz.

You might want a maximum SPL figure for the quadripole - please inquire via email if you have high SPL
requirements in your home system. The Quadripoles are capable of as much or more low frequency output
as you have likely ever heard, but they are high-fidelity subwoofers, not autosound contest woofers,
bass guitar speakers or PA speakers.

To give you some idea, listen to DAFOS by Mickey Hart.  If Gates Of Dafos doesn't 
pin you to your listening chair, scare small children, get people to come running to see 
what happened, smack you in the face with air, and knock objects off surfaces, then 
you haven't heard it, and you don't have
Quadripole Subwoofers from BEAR Labs!!