Adam and I built a set of speakers to give away at one of the Kentucky meets. We used a GRS 10 and turned another 10 into a passive, top end was a Ford JBL 5x7 component speaker. We called them the Sound Troopers. Kinda modeled off a set of Wilson’s.
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Then I’ll need to come up with a different name.
OB Wans (the Open Baffle Ones).
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Perfect name!!!
Classy!
Excellent
Question on inductor placement, for the bottom ½ way woofer.
My preference would be along the side resting on the bottom (visually and support). While the center lines are 90 degrees (inductor with the woofer’s coil) it’s not intersecting. Along the side but placed upward (the pic with my hand) is ~both. Then there is the third pic on the base, again at 90 degrees but not intersecting. This is a large inductor in proximity to a large woofer magnet with its own coil. Thoughts /suggestions ? thx
As long as there is no metal going through the center of the air core inductor, the metal frame of the driver and the magnet won’t have any ill effect. The driver’s voice coil is contained in a closed magnetic loop, so it doesn’t radiate any changing magnetic fields beyond a few millimeters.
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Thanks.
Drivers in, and wired-up. Taking a little break, but hopefully I’ll get a quick / initial miniDSP set-up, and some music going.
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Those look fantastic. No vibration issues from the baffle?
I’m not seeing / feeling any issues.
I sandwiched a ½ and ¾ ply (again each slightly less > total ~ 1 1/8th inch). The woofers are set with them recessed / screwed against the ¾ Baltic birch ply. The sandwich has been glued- so as one multi-ply baffle, directly screwed to the ¾ in vertical side supports. Maybe in addition / partially biz unlike a sealed enclosure- there is no build up / release of any back / internal pressure?
I’m currently listening to my right speaker only as there’s a gremlin in the left channel- I’ll need fresh eyes / head hopefully tomorrow. Guessing there could be an issue with my channel selections within the miniDSP - I biamp and use it for the bass to coaxial crossover and it seems to be bleeding in some bass into the left coaxial.
Edit: Today with a fresh look, I found that I’d swapped the #1 and #2 grounds on the (4 pole) speakONs - the IT at work would tell me ‘error btwn keyboard and chair’… All good to get on with adjusting the active Xover and working on EQing.
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Cool
Looking great. Is this passive or active, what is the mini dsp doing?
Bi amped; with miniDSP active btwn woofers and coaxial, with EQ overlay. The midrange of the coaxial runs from this active full range upward (initially ~400 Hz 1st order HP, may move a bit higher) and the horn tweeter has a passive HP filter (as seen in the pic above the speakON). The lower woofer additionally has a 2.75 mH coil (seen at base of speaker below the speakON) to trim it back (down an additional 3dB) from where the upper woofer crosses with the coaxial.
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I got a chance to play around a bit on the active woofer-to-coaxial crossover. Keeping a 1st order HP on the coaxial at 400Hz seems to work well with the midrange driver, and setting the LP on the woofers LR 4th around 310Hz gets to a smooth transition (around 415Hz +/-). I’ve EQ’d the low-end for the OB cancellations, and the woofers are barely moving so I can look to bump 30ish Hz more down the road. But for now…
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More bass!! 
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More bass, and I’ll look into adding a bit more cowbells as well…ha
Edit: I was able to pull 30Hz up about 3dB from where it was (so now ‘bout -3dB vs -6dB near 30Hz). The beyma 12s shows an fs at 31Hz, so I combined a broad-ish Q bump at 30Hz with a very narrow (20.5Q) -6dB notch at fs.
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Kinda surprised that in comparison with my dual 8 inch 1.5 way sealed low-end (also eq’d, with the same coax top) I’m initially finding I can ‘feel’ the bass more from the dual 12 inch beyma OBs. The sealed 8’s low-end is very tight, accurate, and punchy, but there’s something (for me anyway) with the OBs.
Interestingly that I’m still appreciating the sound presentation of my first real system > maggies with a son of ampzilla. The OB Wons clearly have more low-end, but maybe it’s just something about ones first experience…
Big drivers couple to the air better, making them more efficient at doing their job.
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Due to the side cancelation creating a lobing effect. You don’t get all the room loading that would cause you to pull back the woofer output. So it distills and serves all that direct punch effect as if you were playing a box speaker much louder.
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