Yeah, but I'm trying to "automate" the process as much as possible so that it's just "turn the crank" without a bunch of careful measurements and angle cuts, etc required. Basically since I have metal patterns for the three (and only three!) basic pieces (with a different "A" piece depending on whether you use 6.5" or 8.25" O.D. woofers), you just need to lay these out on sheets of 3/4" and 1" MDF and then use a scroll saw to cut them out (no bevel cuts!). Per "slice" this takes about 24 minutes, then about another 15 minutes to glue/clamp the eight of these pieces together into the basic "orange slice" shape (the "fan" shaped 1/4" plywood pictured in the "jig" is used in "position 1" during this operation as shims under the "C" pieces out at the ends of the slice because the basic "block" is 1/4" less wide per side out there). After glue drys, then you swing the router table into place and run your router (with bit set to just touch the top of the slice out at the extreme radial distance from the "N-S" pole line) over the slice and this mills it to the proper taper angle. Then flip the slice over and use the 1/4" fans in "position 2" (with the ~1" blocks at the end in position under the newly milled surface s.t. they "wedge" the slice up against the head of the "locator screws" out at the ends of the slice and ensure that the piece is precisely in position for routering of this flip side). All this takes ~15 minutes. So say ~ one hour per slice = ~32 hours per sphere. Sounds like a lot of time/work, but you don't have to think about it and it's probably overall less than the time taken using the other two methods of making MDF spheres that I used previously. And unlike the "disco ball" method, this is a true sphere and can be used with 8" woofers (the 5.5" required flat squares of the "disco ball" can only accomodate ~6" woofers...). But like I said previously, the REAL benefit of doing it this way may turn out to be that you can VENEER each "slice" because each slice only curves in one dimension (longitudenal direction) and is "flat" for the ~2.75" equatorial direction of each individual "slice"). After veneered, one could sand down a bit the slight "ridges" at the boundary of each slice for probably an almost perfect spherical look in that direction as well as the perfect spherical curvature in the longitudenal direction....I think a walnut/maple/cherry/etc. 28" dia spherical speaker would look awesome..especially setting on a contrasting wood stand! We'll maybe see...I'll probably put this all aside for a while as/when I have the "jig" done/perfected and maybe pick this project back up if/when I ever "get to" retire....it would really suck up the time anyway. I've priced NEW drivers for these "AOS-III" speaks from humanspeakers.com and using 8" epi woofers (6) and 1" epi tweets (8) it comes to $816 plus $29 for shipping per speaker. I think that's pretty reasonable for new speakers/drivers of this number...
Last edited by elgrau
on Thu Jul 14, 2011 10:45 pm, edited 1 time in total.
FR: 400 disk changer with PS Audio Digital Link III DAC; Technics SL-1100A TT. QED Quenx1 IC's from DAC & TT to Adcom GTP-602 preamp/Tuner. AudioQuest King Cobra IC's from preamp to M1.0t mk-II opt2. QED Silver Spirals 4M wires to EPI 1000’s.
LR: AudioEngine wireless link from family room preamp to Barcus-Berry 2002R Sonic Maximizer to GlowPower Zyxt IC's to Sunfire 300x2 to Nordost 6M bi-source wires to AOS 28" MDF spherical speakers using six 6.5" woofers and eight 1" dome tweeters symm. arranged around the surface.
SS system: CX-995V DVD to AV-634x 3-4 channel amp (center/rears) & M1.0t mk-II opt2(fronts).
Garage: 300 disk changer to Entech 202.5 DAC to MXR150 Receiver (pre) to TFM-42 to EPI 400 speakers.