I’ve been out of the hobby since my last job 5 years ago made me hate my life lol. Been meaning to move on past PA stuff but a lot of this has kind of gone on the backburner along with some curved speakers I was building. Really just want to ride the eskate now and I’m happy enough with the sound setup haha.
It definitely sounds like you have some serious stuff lol
The Tang Band W8-1363SB seems the best choice… One, fed “only” 150W RMS rocked my old convertible from the front passenger footwell, so should do fine fed ~260W.
I worked up a very simple laminated mantle clock shaped box which will house the woofer, amp, speakon jacks to hook up the external “top boxes”, and a power input jack I’ve not modeled. The final design will be 9.25W x 10D x 6.75T (10in across the deck, 9.25 lengthwise along the deck, 6.75 above the deck + the flange of the basket + surround + grille if I add one.) Each of 9 layers is jigsaw cut from 3/4in pine (for light weight… resonance be damned.) Walls will all be 5/8in thick, baffles and back 3/4.
Well, finally have something to show. I’ve tested the Gallo Nucleus spheres with the amp, fed by the ES100 bluetooth receiver, (powered by an adjustable supply set to 50.0V) and am extremely happy with the sound. I turned the voltage down to 30V, noticed no degradation or loss of gain, so it should sound good from full charge to shut-down.
I’d planned to use various and sundry aluminum Gopro mount pieces to enable using the headlight mounts to hold both the speakers and lights. Alas, they were too wimpy to hold the 1lb (ea) speakers. Surplus 7075 antenna mounts to the rescue… Even with only 1 truck screw securing each mount plate, they are solid enough to go try. (I may add a flat plate on top for better clamping.)
For the (absolutely necessary) sub, screw making an enclosure… I finally found a powered subwoofer that fits on the deck and isn’t a complete joke. I hate to waste the weight and space, but its just too easy to throw a $20 20A 12V buck converter at it (vs using the other 2 channels of the other amp that works from full pack voltage.) I’d hoped to be able to replace the internal power amp with my board, but there simply isn’t room.
The mI haven’t decided where to place the small amp board or DC-DC converter, but will be adding a simple wood frame underneath the sub to house 3x 4S1P Lipo packs that will increase my battery capacity by 432Wh (making up for the power drawn for tunes and then some.) There should be plenty of room for both inside.
Still very much a work in progress. Silly, but fun.
I’ll skate around with just the spheres tomorrow, see if they stay put. The DC-DC converter should be here Wednesday. I hipe to be skating with tunes this weekend.
Great work man love too see the plan coming together, this is pretty much how I pictured it myself.
That’s really awesome!!!
Does that have any water resistance at all? Or is it dry sunny summer weather only?
How I missed this
I’ve been building speakers for way more time than I’ve been on a board, so quite a lot, and also have played quite a bit with sound on a board, not actually building, but seeing the effect being on a board has on the system response
I will say this, unless making a massive system that will be bigger and probably heavier than the board, the only answer is going nearfield, this can be as simple as strapping a quality Bluetooth speaker on the top of your backpack, as close to your years as possible
For having the speaker on the board, it’s not impossible, but there are a few things to keep in mind, to have audio quality and clarity, you need between 10 and 20 dB over ambiente noise level, I’ve never measured the wind noise level on a board, but I don’t find it being around 70 to 80 dB unreasonable, so if you want good bass, you need a system that can do it cleanly at 110 dB, the +10dB is for the music dynamics, getting 110dB at 40 to 50 Hz in a compact system is not easy, specially since the speaker on top of the board at bass frequencies is radiating the wave at essentially free field (2pi) so you have less gain than you would have with it close to a wall and way less than you have in a room
I would say the way to go is the same thing I did in a boombox, passive radiators low tunned + a custom eq curve that would have to be found by trial and error that would sound good on a board
I tried a few speakers strapped to my board and all sounded like garbage, but as soon as I strapped my Flip 4 to the top of the backpack it was really good, with a really immersive effect
As you said: Dry sunny day treat. I’m using the other 6 packs to make a 20Ah 12s range doubler in a more hardy case. Likin’ the blue pelican vault.
That boombox you made looks fantastic! The sock w/ top + bottom plates is brilliant.
I agree with pretty much every word and number… I was shooting for 107db max clean at 1m, 101db at the helmet (2m give or take), maybe 95db at my ears (helmet cuts 6db, and not in a friendly way). That woofer, after a peek inside, will hopefully get me under 40hz at said 107db at 1m. . The orbs give 86db/watt. I’d need 21db gain for 107db. 128W rms would give that. I need to measure, but at 8ohms I should have 100W. I’ll be 2db shy. Unless the 100W RMS sub is 88db/w, I’ll be 2db shy there too. Matching failure. If this gear sucks on the board, it will find use on camping trips, picnics, powered by said 12s4p + 4s1p if I can find a practical way to bypass the internal amp. There are 2 boards, both bespoke, with filters on the board with jacks, exposed on the side. Trouble is, all of the power supply circuitry seems to be on the amp board, and there are many interconnections. If it plays ball with the cheap buck converter, it stays 12v. If I want to get fancy, was going to try a slimmer dc-dc converter I could adjust to near max 15.6V for better efficiency.
My dude did you try pushing the subwoofer / low freq speakers toward the ground itself ? We’re literally riding over horizontal walls, that’s a way to halve your field and gain direct reverb IMHO.
And nice sick DIY Boombox btw ! Which wood is that ?
@emaxon Congrats on your Sound board build, looks dope.
Thanks man
Looks promising, did simulate the drives? At those levels you can easily hit excursion limits even with low power and volume, for example, on my setup while I have it flat-ish to around 40 Hz, I can only maintain that up to 90 dB, after that the compressor kicks in
I think Wondom has some high voltage amps that could be driven directly from the board https://store.sure-electronics.com/
@Vanarian Yeah, at those low frequencies even being on top of the board and pointed up or to the side you are still coupling to the ground and getting the gain, but nearfield you still have way more bass while requiring way less power and complexity. I should try the boombox on the board, don’t know if I have the courage to risk damaging it
And thanks, that it’s just MDF, if you mean the veneer I have to see if I have it noted somewhere, but it’s quite beautiful
I think just by virtue of being 6in off the ground, and less off the deck = baffle, I’ll get a bit of gain. At any rate, I’ve made my bed, I’ll lay in it. Waiting for a die cast Aluminum project box to pit the amp in. I left it powered with no signal for a while to see how hot it would get… hot. I may hang the board from the lid by the heatsink.
I’m planning on screwing the 3x3x1.5 buck converter to the top of the 5.5x4.5x1.5 amp box, and screwing the amp box down to the deck with the 4 truck screws.
Since I’ve committed to balanced signal wiring, I’m paralleling the speaker outputs (via 2x NL4 speakon jacks) with one feeding the spheres, the other roited tonthe sub’s high-level inputs.
I’m bringing pack voltage from the Cnlinko charge port to the amp box, then 12V back to the sub with another NL4 plug. (2 poles for high V, 2 poles for 12V)
I’ll have jacks total on the edge of the amp box facing forward. I haven’t decided how to run the 4 wires from the buck converter into the amp box… I may get lazy, just drill 4 holes, seal with silicone or hot glue.
I hope to have some thump late tomorrow or Thursday.
Cells, Hammond box for the amp, and the DC-DC buck converter arrived today. I picked up a 9in square baking pan that makes a perfect cover for a 12S2P booster pack and serves as a mounting base for the subwoofer.
I plan to secure the pan to the deck (with foam padding between the cells and deck, cells and pan, and pan/deck as a gasket) via the flanges… I’ll probably just use a pair of cinch straps.
Since I have a bit of extra room on/in the amp box, I’m going to secure the speaker mount plates to it, instead of directly to the deck. (That way I can use all 4 mounting holes in each plate.) I still olan to screw the box to the deck via the truck screws.
I still need to balance the packs, make a harness before I can use 'em.
It’s too nice out to solder now… Need to get a skate in first 
Balancing board for the battery arrived, but I’ve gotta move out of the place I’m staying over the next 2 days, refinish the floor where my friend expired, and patch about a dozen areas where the previous tenant’s dog chewed up the moldings. Progress this weekend I hope.
The 4S1P packs, with the included BMS, aren’t happy charging in series. (over-voltage protection kicks-in if any single pack sees above 4.2xV, shutting the whole show down.) I need to remove 4x resistors on each board to disable the balancing function, and will likely bypass the over/under voltage cutoff too, let the 12S BMS do the work. I’m stuck with the 4S1P arrangement, (traces connecting the 4 cells in series are on the underside of the PCB, and it’s a ton of work to de-solder all 8 cell tabs just to flip & slice,) so I’ll need to solder 8x 20ga wires between each pair of packs to allow them to equalize, behave as a 4S2P sub-pack. Plenty of soldering work ahead, but I’m still hopeful this will prove to be a decent range extender. Especially since chemistry differs, and I’d like to keep charge/discharge current down to about 5A, I may use one of the DC-DC boost converters earmarked for my car charger to step whatever voltage these sit at up to 50.4V / 5A. (The boost board is capable of smooth current limiting at a constant voltage.) This will cost some efficiency (~10%) but ensure that I never push the extender cells beyond their limits, and can enjoy most of the energy they contain.
There’s too many words I dont understand in this thread but I’m building this 12s6p box top battery with boat speakers built into it for a client.
That’ll work on a huge Lacroix deck… Very similar to the box I made. I tried skating with it on a smaller deck (Landyachtz Switch 40) and either it hung off the deck sideways, or my ankles were practically touching it lengthwise. Either way, I found the sound, firing up at my crotch, to be lacking. Finally, with a single 6.5in rather wimpy subwoofer, the box performed more like a stiff bag… It audibly vibrated until I reinforced the back with a piece of wood, and even then, it wasn’t particularly rigid. I still use it for camping trips, but it just didn’t quite make it on a board. I’m addicted to bass guitar-heavy doom / sludge, and it simply isn’t fun to listen to w/o a decent subwoofer.
haha how did you know it was going onto a lacroix
Cnlinko jack is a dead giveaway. Nobody else uses that plug/jack.
You might tame the box resonance a bit by stuffing it… I’ve been using plastic shopping bags rolled into sausages to stuff outdoorsy speakers with good results.
Good call, I was going to use a bunch of foam padding. Thanks
