Subwoofer for 2 channel high resolution system


What sub is suitable for music. Would like something that would mate well with a system that is transparent portraying excellent sound staging and imaging.
Basically I am looking for a first rate sub for music. One that will disappear, but add the bottom that will take my system up a notch.
Also need balanced i/o, and a high pass to amplifier.
pedrillo
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You will pay as much as a top flight preamp for these, but the Wilson Benesch infrasonic generators are the fastest, most true sounding bass units out there!

they feature they're own amps and have a slew of function capabilities

they can blend seamlessly with box, planar, electrosatic etc...
The REL Studio would be a sure bet. Amazing how it transforms the whole soundscape! I also tried the Stentor and Stadium, but could not come close to the Studio.
I am enjoying a Rel B3 with my modest 2 channel system.

The B3 is purely a very low octave "augmentation" in my system.

Sorry, I do not know about high pass or balanced inputs. The Rel works so well in its recommended manner that I have no desire to try it any other way.

Room placement made considerable and easily audible differences, in both quantity and most importantly quality.