Free Speaker Plans

Frequency: From 40 Hz up to 110 Hz

Enclosure Type: Hybrid

Size: 62x62x62cm

Recommended Driver: icon Kappalite-3015lf (668.37 kB)icon Kappapro-15lf-2 (534.42 kB) and icon kappa-15lf (566.56 kB), drivers with EBP of 100 or higher; Fs (27-50 Hz), Qts (0.21 - 0.41), Vas (150 - 300 L) / (7.4 - 11.1 ft^3). Where EBP = Fs / Qts (strictly speaking it's Fs / Qes)

Cubo 15": Cubo is a multi purpose, stand alone bass bin that will equal or out run a single 18" BR*, of similar size, from ~ 40 Hz and up in terms of sensitivity. Utilising a non-expensive driver such as the Eminence 3015LF, Kappa 15LF and Kappa 15LF Pro** and a cut list from a single 18 mm*** sheet (244 x 122 cm) / (8' x 4') with a single angled cut, Cubo 15" realises a cost effective, small and light weight enclosure following the KISS-principle.

Development: In 2007 the first prototype was build and tested. Cubo 15" is the 4th prototype in a line of hybrides aiming at the achievements as stated above.  The measurement below shows the gain over the stated basreflex (see * for details).

Footnotes:* 18Sound 18LW1400 in a 175 liter basreflex tuned to 37 Hz. (6,6 ft^3) vs. Cubo 15 ; Eminence Kappa 15LF.          ** Apart from these drivers Cubo will work with a wide variëty of 15" drivers preferably with an EBP of 100 or higher; Fs (27-50 Hz), Qts (0.21 - 0.41), Vas (150 - 300 L) / (5.5 - 11.1 ft^3). Where EBP = Fs / Qts.  If you're uncertain if a driver is suited, PM or mail me at This email address is being protected from spambots. You need JavaScript enabled to view it.          *** If you want to use 15 mm material use 11-ply Baltic birch, nothing less. Plans available on request.

Cubo 15 plans are also available in an Imperial version, plan available on request.

Designer: Cubo15 [view profile]alt



Cutsheet (clearly visible after download):



Posted: 2 hours 5 minutes ago by Indi #21653
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This Cubo 15 looks good. I have a 18 mini scoop. I now have bought two 15 fane's and looking to build this Cubo 15 box for them. Would be greatfull if you could send me the dimensions.
Posted: 2 days 20 hours ago by TMH MUSIC #21625
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Hi Mr Cubo. Would love to know what sort of performance I can expect from this enclosure, when loaded with Fane sovereign pro 15-500. I intend to build 2 initially and power them with AX3500, giving 700w to each. Any thoughts from anyone about this cab/amp combo, very much appreciated. Using them to play top 40/live keyboard.
Posted: 4 days 48 minutes ago by Cubo15 #21613
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The Delta 15LF in Cubo 15 seems to be useful from 41 - 43 Hz and up, in return it get's similar sensitivity levels as higher priced drivers.

Best regards

Posted: 1 week 2 days ago by chuck_maurice46 #21598
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OK thanks for the answer, anyone else have delta15LF in this cab?

can someone do a hornresp sim, i'm unable to use this software ^^
Posted: 2 weeks 1 day ago by anjmoor #21590
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I have two cubo 15's with eminence delta 15 lf's in and even using a 1200 watt pa amp just backed off they sound and feel great, i can't even run them full whack as my 12" mid tops wouldn't keep up with them and they are in the extended version
Posted: 2 weeks 1 day ago by chuck_maurice46 #21589
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Hi! awesome cab! what do you recommend with delta 15 LFA? normal or Xtended version? can it sounds good?
Posted: 3 weeks 1 day ago by Cubo15 #21577
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The recommended enclosure for the Kappa15LF Pro is Cubo 15 Extended, though both models will work.

First off, there is MDF and MDF, personally I prefer the latter ;) Also there are wurse and better choices in wood used for construction. The (imho) better choice being 13-ply, 18 mm Baltic Birch or 11-ply, 15 mm Baltic Birch, a wurse choice being 5 -ply or less, lightweight ply.

I've always used M6 (roughly 6 mm) for any PA-cabinet. (M8, roughly 8 mm bolt diameter, M10 roughly 10 mm bolt diameter, etc.). I've tried M8 once and though it feels as an upgrade, it doesn't always fit the mounting thread diameter of the speaker.

Best regards

Posted: 4 weeks 1 day ago by mini-mad #21554
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That picture is perfect!!! That combonation is what you should be using.
Posted: 4 weeks 1 day ago by ramonp #21553
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I think the english term for CHC screws (which is french) is actually hexagonal socket head cap screws or HSHC screws.

I had those in mind when I posted earlier:

Posted: 4 weeks 2 days ago by mini-mad #21546
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Avoid using screws for the driver. For something that will vibrate and not be "glued and screewed" its worth the time and effort to bolt drivers into boxes not screw.

Google "t-nut" and look for size M8 you can buy packs of the bolts and t-nuts or seperate from most good hardware stores.
Posted: 4 weeks 2 days ago by ramonp #21544
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I decided to build my own cubo15 based on kappapro-15lf-2.

What is the recommended build for this driver ? cubo or cubo extended ?

I'm going for MDF wood, is it a correct choice ?

I'm also wondering which fixation to use to bolt the speaker, I'm thinking of CHC screws but I'm confused by the M6 or M8 notation to describe size.
Posted: 1 month 1 week ago by Cubo15 #21495
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@Weloveit: It would work but it's a light weight driver, not in the neodymium, alu basket sense. For starters I wouldn't dare calling it a 400 W driver. From the Sovereign series, the 15-600LF is a good budget driver, that would be my first choice, relative to the 15-400.

@Ramonp: Not authorisation in the strictest sense of the word but I've told them (when they contacted me) that if they have a few clients in a year, I will not bother them but rather wish them good luck.

Best regards

Posted: 1 month 2 weeks ago by ramonp #21477
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Hi cubo, I'd like to know if the people from are authorized to sell cabinets made from your plans ?
Posted: 1 month 2 weeks ago by weloveit #21474
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Hi would anyone know if fane sovereign 15-400's would sound good enough in this? if not could anyone recommend a relatively cheap driver to load it with??
Posted: 2 months 8 hours ago by zkralj88 #21438
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OK, Thanks a lot!

I went ahead and ordered 18NW100. There's no headache in having more :)
(ok, maybe alcohol)

Best regards

Posted: 2 months 8 hours ago by Cubo15 #21437
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Yes, the 15NW100 works best in Cubo 15 Extended or Cubo Extra Extended. The 18NW100 works best in Cubo 18 Extended.

Best regards

Posted: 2 months 3 days ago by zkralj88 #21434
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So it's 15 or 18NW100 in extended version. Right?

Thanks a lot for your help!

Best regards

Posted: 2 months 3 days ago by Cubo15 #21432
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@Duplokit: To my knowledge there are 4 different 4 Ohm versions of the 15" Black Widow, only of which one is suitable. IIRC, the 1505, the 1504, 1502 and 1501 have (a severly) limited Xmax.

@Zoran: The 15NW76 will work best in Cubo 15 Extra Extended or Cubo 15 Extended, it's a good speaker but I wouldn't give it much, if at all beyond it's AES-rating. So if you're into 1 kW plus amplifiers the 15NW100 is a better option, and you'll need the extra power as the 15NW100 will only shine compared to the 15NW76, at the point where it's no doubtly lower power compression will add (it's less negative gain) to the overall SPL-level. Same goes (perhaps even more so) for the 18NW100.

Best regards

Posted: 2 months 6 days ago by zkralj88 #21427
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my name is Zoran, I'm from Croatia.
I have been checking this forum for some time now, but never posted.

I would kindly like to ask Cubo if B&C 15NW76 would fit in to cubo design, and which version.
I'm working out a small system for my band and I thought this could be a potential winner for a small and light bass bin.


Thanks for your help!


Posted: 2 months 1 week ago by duplokit #21411
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Hi cubo I have got my hands on a pair of 15" peavey 4 ohm black widows and I am wondering which way would be best to mount them, would they be best for the extended version?
Regards Iain :0)
Posted: 3 months 2 weeks ago by Cubo15 #21080
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The difference between Cubo 15 Standard and Extended is based on driver optimalisation. Based on the driver parameters of the Kappa Pro I wouldn't go through the hassle of changing one into the other. Especially if you're happy with the current results, if it isn't broke don't try to fix it ;)

If you search for Cubo15 instead of Cubo 15 (so withouth the space inbetween) you'll likely get more results.

Best regards
Posted: 3 months 3 weeks ago by anjmoor #21075
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Search you tube for cubo 15 I have some on there at lower levels lol
Posted: 3 months 3 weeks ago by Vito #21066
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Hello people,

I would like to ask you for one thing. Could you please post a video on youtube of working cubo 15? I would like to see how good cubo15 is :)
Posted: 3 months 3 weeks ago by mini-mad #21026
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Quick question.... would my kappaLF Pros been better off in tthe 15 extended?

Cheers Mr C.... love your boxes. I own four and have yet to use them at war level. Waiting around til summer to give it some.
Posted: 4 months 1 week ago by t.geessounds #20913
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starhaler wrote:
hello Cubo , I'm also interested to build your design. Can you send me the plans ? thanks for your work :) my email is pinoypeso @ gmail . com

the plans is right their look up an u will see the word Plans