The "2b" ( tube, for the uninitiated ) Subwoofer prototype is temporarily assembled and functioning. I was horrified ( but not @ all surprised ),when the initial test run seemed to indicate a rather severe harmonic resonance of the speaker itself. After some observation, I found ( to my relief ) that it was the plate amplifier vibrating against the cylinder wall. A little adjustment and tightening and I was somewhat amazed that the little "2b" sub sounded fairly good.
The unit is basically a Dayton SD215-88 8" Shielded DVC Subwoofer, driven by the Dayton MCA2550D 2.1 Channel Class D Amplifier built into a heavy 11 inch cardboard tube (empties from work, thanks guys) sealed enclosure. The amp has independent high and low frequency amplifiers, a variable subwoofer crossover and internal short circuit protection ( which I inadvertently tested on initial hookup, oh s#iiiiiiit! ). The subwoofer LF amp is rated at 50 watts RMS @ 4 ohms, and the HF amp at 25 watts x2 RMS @ 8 ohms, which is currently driving the omnidirectional "2b" 3 way towers quite nicely. Plenty of power here to drive a set of efficient speakers well beyond any volume level that I would care to experience, thank you. You can cook with 1000 watts, you don't need that kind of power to listen to music or watch a movie for cryin out loud. Besides, I've replaced every light bulb in the house with compact fluorescents so it seems a bit counter productive to waste the savings.... 
The entire concept here was to build a relatively inexpensive ( as cheap as friggin possible ) multipurpose 2.1 sound system, I really don't have any need or desire for a 5.1 or 7.1 surround setup, they're just overkill if you ask me. Building a center channel speaker ( making it a 3.1 system ) might be an option at some point if I were to use the setup for movies or tv on a regular basis. There are quite few nice home theater in a box and computer speaker systems available that might end up being less expensive and better sounding than the Peabody "2bz" system, but there is just something about designing and building your own stuff that increases the enjoyment factor of the experience exponentially...
The HF amp will eventually drive a pair of 2 way omnidirectional "2b" towers consisting of Tang Band W4-656SC 4" Full Range Drivers and capacitively coupled Pioneer FD66AP45-13F 2-1/2" Cone Tweeters, which I am currently using ( tweeters ) in my 3 way 2b's, they're very smooth and natural sounding and have a wide frequency range. I prefer a paper cone or fabric dome tweeter over the mylar type, as the few mylar's I've tried were a little harsh and seemed to almost sizzle at times. The 8 inch sub is decent although not overly detailed or articulate , I toyed with using Dayton's reference series 8 inch, but at $96.00 a piece, the $28 buck cheapie is sounding better all the time. All of the electrical components were purchased online @ Parts Express, they have the best selection of equipment by far, in my opinion. A great website, lots of feedback and product reviews from people who actually know what the heck they're doing. (link) parts-express.com
I almost hate to disassemble this thing to finish it, as I'm really enjoying the added bass response (which is somewhat lacking in the 2b 3 ways). But back to the lab it goes. Formby's Tung Oil finish for the oak end plates and legs and the special Peabody Labs sound dampening coating for the cylinder (rubberized undercoating).The obsession with cardboard tubes continues... Now to get started on the minimalist 2 way "2b" towers....
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