Originally Posted by audiofan1
Disclosure first I own an Rythmik F18 and 2 other subs in my avatar and not an attempt to further derail this thread but which servo are we speaking about? As I was under the impression the late audio legend Arnie Nudell was the inventor of the servo back in 1968.
The servo statik 1--it used a "sensing coil" on the voice coil so not a "real servo"... If you want a real honest to god servo, that would be the Servo Drive back in the 80's. An interesting beast with a servo motor that used belts to move the cones--now THAT is different. Here is a review on the model made for home theaters way back when...
You asked--jusssss' sayin'....
From what I recall, Phoenix Gold came out with a rotary vane sub for cars back in the 90's--not sure what happened to that idea. Of course, now you can get a rotary fan woofer is you want to plunge into the depths--yes, a fan that will twist it's blades back and forth to change frequencies.
Cost? Well...if you have to ask sort of thing.
The most interesting tech I've seen lately with subwoofers is the PowerSoft M-Force which uses a moving magnet with the "voice coil" wrapped around it. I hear they are just starting to roll out by a company called Rat Sound--it is a professional nightclub/arena type device. Samsung has talked about using processors that predict the distortion of drivers and will counter that distortion before it happens--not sense it to do it afterwards. That sounds pretty cool, to process the signal then apply correction to it as the processor has all the data to do that properly. The ironic part is what Samsung put this wizardry...in a sound bar! Yeah, the truth is stranger than fiction. Not sure what they are doing with driver processor correction in real time, I'm sure now that they own Harman International--the JBL/Revel engineers are playing with it. If it works, that is the end of sensing coils and I would expect really good performance from such a device.
I've never torn apart a Rhythmic sub personally--but I know if it had an actual servo motor in it with direct or belt drive somebody would of noticed. They most likely are using a sensing coil of some type which makes sense. Not often you'd see a sub that provides a free can of belt dressing. Fans, rotary subs, servo belt driven subs and the interesting M-Force mega motor 30 to 40 inch subs--pretty cool to look at some of the ways that were tried over the years and even today.
As far as Samsung's predictive actice corrective processing for speakers go, is it just me or is waiting for technology to "trickle down" from sound bars just.... bizarre?
Back to the OP, very interesting results with 2 subs strongly in the lead and 4 subs to be quite common--who knew?
I'm filling peer pressure to fill up my living room with subs--but then where would I put them when my wife throws me out of the house? The van by the river won't hold a bunch of subs. I guess I'll be happy with three of them--missed being the cool kid by that much! Story of my life...