Tough decisions, tough questions

[Raider]

Raider,

Are you interested only in new products? A line Klipsch produced several years ago (KSP) might fit your bill. I own the KSP-400s (built-in subs), and they're terriffic for HT. You won't get too many recomendations on these, as not many folks have heard them. When they pop up on eBay, they're usually bargains (the 400s listed for $3500/pr., but routinely go for under a grand on eBay).

Thanks for the tip. I'll check this out. Any concise place for info on this product ( I take it it is no longer in production).

[Raider]

The subject of compression, heat buildup, and distortion is discussed on the Rhytmik site. I'd be interested in your comments on that data. The servo also allows a .5 q overdamped alignment which I like in a relatively small enclosure. I am considering this option for the studio/office application where less output will be required and accuracy and low distortion is premium. I am actually looking at the multiple driver option for the HT apllication, for just the reasons you cite. I am finding that the bass response is so solid and low on the Klipsch alternatives I am considering that I'm having to reconsider options. What will be needed is solid response only on the lowest octave, with no distortion, and crossover flexibility to allow seamless integration with the excellent bass response of the mains. Such output in this octave requires power and displacement, or a horn the size of my second floor. I've ruled out IB due to noise considerations in the neighborhood, but an attic space adjacent to the HT area will allow large sub enclosures to be built into the wall. Would it not be best to fire suc a sub into the corner of the room?

Hmmm...interesting discussion on their website. I don't disagree with anything they said, but they did seem a bit narrow minded talking about the same 3 distortions over and over. I would very much be interested in what they think is their biggest limitation/tradeoff. Though it definetly sounded like it was written by an engineer that absolutely believed in what he was talking about. Does their system only work with their driver, or does it have the flexibility to work with other drivers too?

The main tradeoff is sheer output, as far as I can tell. Additional cost too. The concept

The

can be used with any dual coil sub; however the designer says that you give up about 3db efficiency. His driver is built by TC Sounds, and uses a much smaller guage wire for the feedback coil winding, which helps reduce voice coil weight. For accuracy this seems a good alternative for music; for HT apps maybe less so were sheer output is needed for effects.

But if you have free attic space for building large enclosures then I would definitely recommend going that route. All the fancy tricks aside, the bigger the box the better it will perform.Something like a few Dayton IB15's powered with a Crown XTi (built in DSP) sounds like an awesome setup. Put a 16x16 manifold just above each corner with the drivers firing at each other on opposite sides (so that the mechanical vibrations cancel themselves out). 10 cubic feet per driver. You can expect a peak around 130dB with good extension down to 10Hz.

By the backwave firing into the attic, which by venting is open to the neighborhood, would this not potentially lead to problems? Or does te loose insulation serve as enough of a bass trap?

[DrWho]

Oh no, you build an actual 10 cubic foot enclosure behind each driver (or if you have 4 drivers then a 40 cubic foot enclosure containing all of them). You actually don't want to go much bigger with the Daytons because you want to control the cone-excursion down low. This enclosure would then sit inside the attic, it keeps you from having to brace your entire attic like a giant speaker cabinet.