Yet Another (3rd!) Way to Construct a 28" Spherical Shell...

Thanks PDR et al! Have we seen your DIY speakers? If not, please post! Yes; was a lot of work, but "fun work". Time to enjoy the music...for a while..lol!
I added some 3/4" PVC pipe "shielding" to the exposed Nordost wires last night leading to the underside of speakers...as protection from my dog (who chews EVERYTHING). He's shown no interest in "wires" to date, but you never know. I have ~$400 in these "used" bi-souceable wires (including $200 to have the amp end of these wires modified by Nordost factory to have 4 connectors for true bi-source capability). I love my new doggie....but would not want to come home to THAT dissaster! (he recently mauled our TV remote: but that's a free replacement from Verizon...and I can live w/o TV...but not music! lol).

I have dogs as well Ed.....sometimes you want to strangle them, but that goes for my kids as well.

I have a thread here somewhere listing my DIY.....I have started another build so I'll up date it.

Enjoy your listening time.....after all the work thats the reason.

Ed...they look like 2 mines!!!!! Really...how do they sound? I know you put alot of time and energy into these. Is the bass what you expected? I would expect the imaging to be a reflective/direct mixture.

Ed...they look like 2 land mines!!!!! Really...how do they sound? I know you put alot of time and energy into these. Is the bass what you expected? I would expect the imaging to be a reflective/direct mixture.

Wow! I didn't think of that. It looks like a WW2 anti ship/sub mine!

sub mine.jpg (98.38 KiB) Viewed 142 times

The tweeters (on #2) are not yet broken in, but the sound is so far VERY nice. Imaging is much improved with now both identical (when different, as I did have - one with 6.5" woofers and one with 8" woofers) even a slight difference in sound from left to right speaker can make each speaker "too independent"). Now it's seamless and very "smooth". As noted before, they do have a slight "bass bump" that is probably due more to room acoustics - especially the one diagonal in the corner of the living room which probably "funnels" the low frequencies into the room - (this bass bump did not seem to show up when I drug #1 from the living room into the family room and did the response curve measurement there). On some songs this is a plus... But I set the bass -2 db tonight and it was REAL nice. As an aside, I have a feeling that due to most tube amps being a bit lacking in bass response, that these speaks (and/or room position...) might be a "natural" for say a ~100 w/c tube amp.... But I listened quite a bit today via the 300x2 (took half day vacation....and a full "sick day" on Wednesday... to finish them) and everything sounded better, clearer, smoother, and fuller than the 6.5" woofered sphere's. So far I'm very pleased...

Right on, now you have a chance to relax and just listen to some good tunes.

o One of the main advantages of these new ones I made (using "orange slice" method with 8" woofers) is that since they are veneerable, they are just beautiful to look at (as opposed to the silver painted 6.5" version with sphere construction method(s) that DON'T allow for veneering). This is important re "wife blowback" issues (if applicable..) but also for the overall effect on the sound and listening experience. Even #2 is better than #1 in this regard because the surface of #2 is smoother and reflects back a warm, shiny glow from the nice brownish Teak wood veneer...#1 is not quite as "shiny" (which I'll fix partially by adding the same 3rd coat of shellac that I did to #2). The teak wood color of #1 is redder than #2 which is browner and thus warmer as well. Lesson learned: buy ALL of the veneer for BOTH speakers at the same time (and place). The place I bought the teak for #1 from had discontinued it by the time I got around to buying it for #2...

o The sound is better than the 6.5" versions (after a break in period for the tweeters: happened for mine sometime early last weekend: clarity and stereo imagery and general "now it sounds RIGHT" all noticably improved around that time (~12/14....I finished #2 on 12/5). Sound is for sure better than the 6.5" EPI woofer version of these round speakers (especially at high volumn..). My "sound memory" tells me that the 8" one's are better, but there is still something about the 6.5" EPI woofer sound that I really like...and something about it that I don't like (as well as I do the 8" woofer sound...notably better detail as heard/demonstarted in the EPI 1000's I have in family room system). This (surprisingly similiar good sound of the 6.5" version) COULD be related to the fact that the 28" diameter (26" inside diameter) sphere volumn is exactly 1.5 times that of the EPI 400 towers that have four 6.5" woofers so therefore the "right size" for an enclosure with six 6.5" woofers would be 1.5 (6/4) times more. On the other hand, this is NOT the case for the sphere's with the 8" woofers: using this same logic, one would need a 42" (~40" inside dia.) sphere to yield 1.5 times the volumn of the EPI 1000's (that have four 8" woofers). This lack of adequate(?) volumn may or may not be effecting their overall sound quality... I COULD make a 42" sphere enclosure (from HW??), but that borders on very impractical and besides, I'd need to "re-tool" to do that (basically could be done with 48 "orange slices" of the same width, but of course heigth of each slice would be 14" more... Not going there...just too big and bulky and more effort that I want to expend. I am, however, building a "tool" that will take the two current 6.5" woofered speakers (AOS-I and AOS-II) I have and mill the 32 facets into their surfaces (like the "orange slice" construction method produces) so then I could HW veneer these enclosures as well and not have to go to all the work of building two more from scratch. This is my new project - pics of this "milling machine" to follow, which is basically a jig to hold/rotate the round speaker in just the right place and also a guide for the router to mill these facets precisely into the surface of each (currently) unmatched speaker (this works because electrically/driver wise they ARE matched). Then I will veneer these two round speakers (AOS-I and AOS-II) into matched beauties! Have not yet decided what HW veneer to use...price for enough veneer to do this ranges from ~$100 to ~$500 per speaker..but that's a LOT cheaper ($'s and hours) than building from scratch!

o Overall, I think there IS something to "spherical dispersion" re these speakers and/or the extreme detail made possible by 14 drivers (all eminating from a point source...). The sound is very full and detailed and very smooth. Re the measured "bass bump" (that COULD just be room acoustics): this might make these speakers (or room diagonal positioning of speakers in general) a natural match to a relatively high powered tube amp due to the fact the bass response of MOST tube amps is somewhat lacking...so could be a good synergistic matchup, I don't know. I have listened to them with the bass attentuated -2 db....sometimes this sounds better, sometimes that "extra" bass is better... To each his own...

Mahalo! Merry Christmas to all of you ...and to me! : I have a project to work on over the break! To me, that's what life is all about: having a project to work on that one is passionate about. Be that making a million dollars, helping to cure world hunger, whatever! Just Do It! - Ed

Holy cow these look fantastic, between you and PDR there are some serious speaker building skills here. I can't believe you were able to build these let alone veneer them on top of that. It makes my head hurt just thinking about it

Update/fini on these speakers: All done re-finishing/veneering AOS-I and AOS-II (so that they both look the same). Temporarily have them both (AOS-I and AOS-II) in my living room system - see pics - (with the 8" versions...not hooked up). Sound is more "neutral" and not as big as the 8" version and I'm sure not as capable of LOUD as them. Wondering what "mix and match" would look like via switching the stands on the pairs but that's more work than I want to do. Will listen to these this weekend and then go back to the 8" version. Any preferences (looks/color/finish wise)? Bottom line is that I spent about ~1000 hours on all four of these speakers including all the time making the arc cutter, templates, jigs, the "milling machine". Probably about 125 hours or less to build one now with all the "support equipment" done. About $1350 in each pair including drivers (whether vintage used EPI drivers from ePray or new PR drivers from Humanspeakers.com the cost of the drivers is about the same...), MDF, HW veneer, glue, x-over caps, finish, sandpaper, wire, the stands (or $2700 total in both pairs and ~500 hours of labor). Definitely had my fill of speaker building...forever or for a while:

IMG_3771 (Custom).JPG (118.72 KiB) Viewed 8 times

IMG_3772 (Custom).JPG (66.9 KiB) Viewed 8 times

IMG_3769 (Custom).JPG (75.21 KiB) Viewed 8 times