The
Betsy is about as inexpensive as they come, primarily because I have no distributers and keep her pedestrian looking. They are exactly $100 a pair, but I did recently have a
sale/promotion that you might be interested in. The Pioneer BOFU is less expensive, but you would probably need to add some series resistance to use it on an OB. But then you end up with fairly low efficiency. And by the time you add supertweeters (which they require) you are close to $100 anyway. PE has a $9 "ceiling speaker" fullrange. But it has a very, very high Qts. You'd likely find the bass to be boomy and lacking in extension, but they could be a fun experiment.
I have not built a JE Labs style baffle. It looks a little small to me (compared to the effective dimensions of the
U-baffle I use). Keep in mind that the amplifiers JE and company use will all have a high output impedance, which increases the effective Qts of the speaker. That means they don't need to have speakers with as high a Qts to get reasonable bass. With your Onkyo, you are going to need a speaker Qts around .7 for it to not sound underdamped (bass light). The U-baffle, BTW, is based on the
Darkstar thread here at AC, which predates WBAL. Do check it out for useful OB info.
8" is a pretty good size, BTW. Drivers can only move so much air in an OB, and the 8" is just enough to get the job done for most people in moderate sized rooms (provided you are listening somewhat nearfield). Also, speakers generally get more efficient as they get bigger, so smaller drivers may not be enough for smaller amplifiers. 8" speakers can also get enough high frequency extension to satisfy most folks, whereas most larger fullrangers require a supertweeter. The budget larger fullranger is the Emminence 12LTA, but notice the HF on the response graph. A 12" driver's whizzer starts to look like a woofer. And, of course, bigger speakers cost more. So, all-in-all, 8" is very popular due to the balance of bass and treble performance.
FWIW, OB's are easy to experiment with. If you were to build the U-baffle I choose, you could build multiple baffles for the center. Then, if you find an interesting vintage 12" (EV, for example) on Ebay or craigslist, you can swap in and compare.
Drop me a line if you are interested in the Betsy, but I'd be happy to discuss OBs here as well.
Paul
www.wildburroaudio.com
