Discontinued, here for archive only
10" high excursion subwoofer and 250 Watt dedicated amplifier designed for single subwoofer applications
The chicken, the egg, and the chicken coupe all arrived at once.
The vast majority of subwoofers available today were designed using existing drivers and plate amplifiers, hence the designers were unable to take a system-oriented approach to engineering the product.
The North Creek approach is to define the optimum parameters first, then design the system to meet those parameters.
The North Creek Poseidon subwoofer was conceived of as a system. The driver, the amplifier and the cabinet were optimized together to fulfill our design goals, providing the cleanest, tightest, most articulate deep bass we have heard. We feel the North Creek Poseidon to be the ultimate statement in small subwoofers for today's most demanding applications.
For a subwoofer to perform optimally in both two channel and home theater applications, it must:
Both the front-firing and down-firing version of the Poseidon share the same driver, the Peerlexx XLS-10, a design with enormous strength for a very low Qts, a self-cooling voice and extremely high excursion capability. The combination of the and our acoustic suspension cabinet yield a Qtc of about 0.30 in the neighborhood of 30 Hz. The central benefit of acoustic suspension loading is that it provides the lowest distortion at high excursion, hence the cleanest deep bass, while limiting driver excursion below resonance. In this application, the driver/cabinet combination is 10dB down at system resonance, and the low Qtc means cone motion is optimally damped.
Matching this driver/cabinet combination is our 250 Watt dedicated amplifier, which combines 6.5dB of bass boost at 25 Hz and a third order subsonic roll off. The product of the amplifier and driver/cabinet transfer functions yield a system exhibiting frequency response that has a very gentle 2dB frequency contour from 75 Hz to 25Hz, a -3dB point of 25Hz, and a fifth order roll off below 20 Hz. The possibility of overexcursion is eliminated by the amplifier high pass roll off, and the woofer motor is capable of thermal dissipation up to the amplifier's power limit.
The high frequency low-pass section of the amplifier is also third order, switch selectable at fixed frequencies (55, 80, 100, 140 Hz, bypass). Switch selectable is superior to "infinitely variable" low-pass crossover frequencies because it allows the left channel to be precisely matched to the right channel, and incorporates much better sounding discrete components. Likewise, the third order slope is a good match to acoustic suspension satellites and a perfect match to aperiodic and first order high-passed satellites.
All told, the North Creek Poseidon subwoofer system provides exceptionally dynamic, clean deep bass, a tight mid-bass, and rolls out quickly to allow the satellites to perform at their best. The system design approach has yielded a subwoofer that surpasses all of our design goals while eliminating the shortcomings of subwoofers designed using existing drivers and amplifiers.
The Poseidon kit includes the Peerless XLS-10" driver, dedicated amplifier, cabinet stuffing, NCMS soft glue, Big Toe spikes, and all required mounting hardware. Everything except the wood.
Discontinued, here for archive only
Acoustic Suspension, Vab = 1.5 cubic ft., Qtc = 0.30, fc = 33 Hz.
Here's a photo of my finished Ikemo's and Poseidons. It was a long haul getting them done, but well worth it.
I'm currently running the Ikemo's as mains and side surrounds, while I contemplate which kits to build for the mains and center channel, but even running what is probably your lowest priced speaker, the sound is fabulous. I'm inclined towards the Vision Signatures and Vision-C Signature, so I imagine the upgrade will be remarkable.
These are just as advertised...Musical, large soundstage, well balanced, and great full range sound with the addition of the Poseidons. The level of detail is wonderful. It's nice to enjoy listening to music again, and the home theater experience is terrific.
It is a pleasure to work on a project where you can communicate so readily with the designer, and get help with questions that arise in the course of construction. The woodworking aspect was great fun, and the reward at the end beyond satisfying.
Looking forward to future projects,
La Madera, NM"