Eminent Technology LFT 7 !!


Not a missprint!  LFT 7 was the LFT 6 with additional bass panels. The bass panels had 3 bass drivers per panel.  4 panels total.  Would like to hear them or purchase them.  
128x128riverdinaudio

THE sub for planars is the GR Research/Rythmik OB/Dipole Sub. This has been discussed on Audiogon numerous times in the fairly recent past, so I won't bore everyone again with the reasons why. ;-)

Yes, the swarm is a great thing, but an OB/Dipole sub is more appropriate for planar loudspeakers. No reason you can't have four of them!

Yes I believe in the Swarm bass array.  I currently own all components, cabinets made, for 4 Dual driver GR Research Servo Subs modeled after the GT Audio Works system.  So assembly will begin shortly.  My main listening room is 22x53x10 and is being remodeled.  I decided to go this way only because I have always wanted to experiment with servo controlled bass drivers and the cost to do so has become realitively reasonable.   I am not tied to OB/Dipole for bass but it is possible.  The PAP Quintet 15 proves that.  The Linkwitz Lab lx521.4 proves that.  For sub bass closed box is best to my ears.  Tastes varies.

Because both the GR Research/Rythmik OB/Dipole Sub and their standard sealed enclosure subs (the F12G in the case of GRR) employ the Rythmik Servo-Feedback system, the difference between the two is not as great as it would be sans the servo. Each has it's own strengths and weaknesses in comparison to the other:

Sealed provides more output, OB less room loading as well as dipole characteristics matching that of planar loudspeakers (not just out-of-phase cancellation to either side, but also equal SPL drop off at varying distances, keeping the speaker/sub balance the same at all listening positions.). Not to mention no sealed enclosure resonance issues!

Hello riverdinaudio,

      I have listened to numerous high quality subs including dipoles but have never listened to OB or any GR Research subs.  My only experience utilizing 4 subs in a distributed bass array (DBA) configuration is the Audio Kinesis Debra 4-sub complete DBA kit system I bought and installed about 5 years ago in my 21'x15'x8' room.  This system is identical in price, sub amp/controller utilized and concept to the AK Swarm system except the Debra subs are more rectangular at 12"Wx14.5"Dx28"H.  
     I initially used Magnepan 2.7QR 3-way 6'x2' dipole panels as main speakers with no room treatments, DSP room correction or EQ and ran them full range (35-20K Hz) with all 4 Debra subs operated in mono, without the port plugs and a 40Hz cutoff frequency setting, so all 4 subs in mono and  ported configuration operating between 20 and 40 Hz.
     This setup provided what I consider near sota bass performance in my room that was fast, smooth and detailed enough to seamlessly integrate with the 2.7QRs while still providing the powerful deep bass impact and dynamics I felt they lacked.
     A couple months ago I upgraded to a pair of Magnepan 3.7i main speakers, which are the same size and 3-ways but have the true-ribbon treble transducer instead of a quasi-ribbon transducer, and fully treated my room with $3,500 worth of custom installed GIK room treatments.  You can view my recently updated system pics to view the results.
     Long story short, the true-ribbon treble section and other 25 year newer technology of the 3.7i main speakers, along with the room treatments, significantly improved the overall detail, sound stage imaging, naturalness, quality, realism and overall enjoyment of my system. And I  perceive the sota bass performance and seamless integration with the new 3.7i main speakers provided by the 4-sub DBA system as even more  impressive, which I didn't think was possible.
     So in summary, I'm stating that I'm thoroughly convinced of the 4-sub DBA concept's effectiveness in my room and believe you'll be thoroughly convinced if you deploy one in your room.  However, I'm not stating that 4 high quality GR Research/Rhythmik OB or servo-controlled sealed subs wouldn't perform and sound equally as well or better in a DBA confguration, because I've never heard them and just don't know.

Best wishes,
    Tim
Damn Tim, 3.7i's and the Debra Swarm. I would without hesitation take that over the 3/4 million dollar Wilsons. A lotta loot left for music!