Benny has been after Brian about his direct-servo Rythmik subs since his very first post on AVS... it was in a response to a posting I made directed to Brian asking about particulars of his direct-servo implementation. The bottom line is Benny doesn't think Brian's implementation of his 'direct servo' qualifies as a bonafied servo circuit because it lacks a mechanical transducer of some sort as its sensor... however this is Benny's own interpretation of what a "real" servo system should be. (Here I just thought you needed a path for feed back from a sensor, a control circuit and a driver... as far as I'm concerned Brian's subs meet these requirements.) Quite a while back I came across a couple patents on what appeared to be circuits similar to Brian's direct servo (apparently one of these patents is what Benny referred to a few postings above) and apparently Sony did implement one of those patents calling the sub a "servo" at some point... I posted about this find in a thread where someone was asking about Sony's servo sub (its what prompted my Internet patent search in the first place). I'm not an EE, (though I am actually an Engineer in another discipline), so I don't really understand how Brian's patent differs in its technical merits, but apparently it does since he was granted a patent on it and he hasn't been sued.
The 'discussion' here (and elsewhere where Benny keeps bringing up Rythmik's direct-servo implementation) is essentially about types of distortions and which are worse and what values are going to be audible, etc. This type of esoteric rhetoric I find mind numbing and quite frankly useless especially in light of the fact that Benny has never even listened to a Rythmik. He is all about the theoretical discussion and not about relating it back to any actual experience. So when he actually has the chance to listen to a properly set-up and integrated Rythmik sub and to critically evaluate it with familiar source material, ONLY THEN will his theoretical remarks begin to have any real value and weight... until then it begins to just sound like a lot of blah, blah, blah, Rythmik is not a servo sub, blah, blah, blah, Brian is a huckster blah, blah, blah, Rythmik subs are full of distortion, blah, blah, blah, I like Velodynes... 80+% of all his 64 postings here on AVS has been specifically dedicated to 'exposing Brian and the terrible subs he designs'.
Benny, either go and actually experience a Rythmik or give it a rest...
"For deep bass, the listener is not really listening to the speaker, but rather, is listening to the room as it is being played by the speaker."JuicyDoggie Jabber