Free Speaker Plans

Cubo 18:
Cubo 18 is a multi purpose, stand alone bass bin that, like Cubo 15, will equal or out run a single 18" BR*, of similar size, from ~ 40 Hz and up in terms of sensitivity. Cubo 18 works with a wide variety of 18” drivers. It has a cut list from just over a single 18 mm*** sheet (244 x 122 cm) / (8' x 4') with a single angled cut. Cubo 18" realizes a cost effective, small and light weight enclosure following the KISS-principle.
Development:
In 2007 the first prototype was build and tested. Cubo 18" is the 5th prototype in a line of hybrids aiming at the achievements as stated above.  Cubo 18 Standard and Cubo 18 Extended will both work with a wide variety of drivers, if uncertain which one will be most suited, build Cubo 18 Extended or mail me at This email address is being protected from spambots. You need JavaScript enabled to view it.
Size: 62x62x65cm (HxWxD)    
Frequency: From 40 Hz up to 110 Hz    
Enclosure Type: Hybrid

3D Model (by K-M-Sound-System):

Cubo 18 Rebated 6mm:

 

Cubo 18 Extended Rebated 6mm:

 
Footnotes: 18” drivers preferably with an EBP of 100 or higher; Fs (22-42 Hz), Qts (0.25 - 0.58), Vas (200 - 450 L) / (7.4 – 16.7 ft^3). Where EBP = Fs / Qts . Measurements will follow.
 
Cubo 18/15 (difference): Cubo 18 is 3 cm (/ 1 1/6th inch) deeper then Cubo 15. Due to phase similarities Cubo 18 and Cubo 15 can be  used together without noticeable issues. Cubo 18 has on average slightly more output for a given input in comparison with Cubo 15 (based upon electro-mechanical relatively similar drivers), especially between Fc high and Fc low,whilst Fc high and Fc low, remain similar (= cut-off frequency).
 
 
 
 Cubo 18: Front view
alt
 
Cubo 18: Side view without side panel
alt
 
Cubo 18: Driver for comparison
alt
 
Cubo 18: Detail magnet and bracing
alt
 
Cubo 18: Magnet facing out
alt
 
Cubo 18: Magnet in chamber
alt
alt
alt
alt
alt
 

Posted: 1 week 1 day ago by Cubo15 #22202
Cubo15's Avatar
As far as I get from the post, e-mail and PM, you want a very detailed building plan. I'm not really into that nor do I have it (tho can't speak for the others), I would just look through the thread for pictures of how others shaped their cabinets and pick the ones I like best from that.

Best regards

Cubo
Posted: 2 weeks 1 day ago by jazs #22154
jazs's Avatar
Hi would there be anywhere to get hold of more detailed plans for the cubo 18 looking to build 4 for myself ... plz help

thanks
Posted: 2 weeks 1 day ago by MattMoon #22150
MattMoon's Avatar
If You wand something from top drivers BC or 18Sound try their enclosures. There are great.
Cubo is a perfect cabinet for budget drivers and you can have really hi spl for low price.
Posted: 2 weeks 1 day ago by MattMoon #22149
MattMoon's Avatar
HI
I'm looking for cnc project for cubo18
Anyone?
Posted: 2 weeks 1 day ago by Cubo15 #22147
Cubo15's Avatar
For those interested in Cubo Kick: freespeakerplans.com/kunena/7-general-fo...0-cubo-kick-15#22146


Having a budgetary Cubo 18 driver and switching it for a high cost driver might make a 1 or 2 dB difference if everything else stays the same. The highest output 18" driver in Cubo 18 will keep up with two Cubo 15's loaded with the Kappa 15LF. To do that it needs a 2000 W continous amplfier and suitable high pass and low pass (i.e. decent DSP).

Having a high cost driver will do something, having loads of power will do something on top of that, using keened out DSP will do something on top of that. Also having the cabinet made out of the right material by the right people will become more important as the SPL level rises.

Best regards

Cubo
Posted: 2 weeks 2 days ago by crossed #22144
crossed's Avatar
So a question Ive had for a while is about the difference in speaker quality. I have Cubo18 extended with eminence sigma pro18. How much beter would it sound with speakers that cost much more? I just have no frame of reference when it comes to this stuff because where I live it is only, old, bottom of the line, store bought systems like peavy. How much beter is the sound of my budget speakers compared to a top of the line speaker like the PD1850? The PD is about almost 3.5x the cost of my speakers, but if the outpout is 3.5x more it would be worth it.
Posted: 2 weeks 3 days ago by thohaug #22131
thohaug's Avatar
Thanks.18NLW9601 it is then. Looking forward to testing these bad boys.
Posted: 2 weeks 4 days ago by Cubo15 #22119
Cubo15's Avatar
For me that would narrow it down to these:

18NLW9000 (with the magnet in the horn)
18NLW9601 (with the magnet in the chamber)

Best regards

Cubo
Posted: 2 weeks 4 days ago by thohaug #22118
thohaug's Avatar
Thanks for the answer, as to how much power: I got 2x crown itech 4000 amps to drive 4 of these, so power limitations should not be the biggest issue. It maxes at about 2000watts 4ohm per driver.
Posted: 2 weeks 4 days ago by Cubo15 #22115
Cubo15's Avatar
Hey cubo, Im thinking about upgrading the drivers in my 4 cubo 18 boxes
I would look into the following T/S-parameters, for the L8G401 these are Fs 33 Hz, Qes 0.3, Vas 268 Liter, n0 3.1%, Hg 12 mm, Hvc 23 mm (4" copper VC or larger) and if still unsure Mms. As n0 is quite high, for the best improvement, I would look for a high n0, similar Vas, Qes 0.3 or lower and Hg around 12 mm kinda driver.

The rest depends on how much power you have available, so if you answer that, I'll know enough. I would recommend one of the following:

LF18N451
18NLW9400
18NLW9000
18NLW9601
PD1850

A 21" would improve output below 50 Hz but not above. As it's excursion is low compared to an 18" driver, it's in actual danger of over heating as it's barely moving.
I would try the cubo kick...
Cool, if you send me an e-mail at questionsaboutcubo.at.gmail.com I'll send the plans from there.

Best regards

Cubo
Posted: 3 weeks 17 hours ago by t.geessounds #22101
t.geessounds's Avatar
Cubo15 wrote:
The consensus is that Cubo's have the same "throw" as a reflex cabinet but louder, as you have used 18" reflex before I guess you know what to expect when used outside.
I've noticed that Cubo Sub throws a bit further. If one would say a Cubo 15 throw's up to 20 meter, than a Cubo Sub would throw up to 30 meters, whereas a scoop will throw 40 - 50 meter.

If cabinet size/portabilty isn't an issue, you could try Cubo Sub instead, that would also make sure you aren't missing any lower notes. The L18X451 is a great driver for sub duty and will work in Cubo 18 Extended and Cubo Sub equally well.

Do yo need plans for 15" kicks as well? I've been working on Cubo Kicks for quite some time now and I basically just need a few people tell me how great it is before I dare launching the plans officially. The benefit is that it's for 15" drivers, stacks and looks nicely with other Cubo's and is easy to build as well.

Best regards

Cubo
I would try the cubo kick...
Posted: 3 weeks 1 day ago by thohaug #22098
thohaug's Avatar
Hey cubo, Im thinking about upgrading the drivers in my 4 cubo 18 boxes. Currently using rcfl18g401 drivers, but wondering if I might be able to squeeze some additional spl from them. Im wondering if you know which driver that will be able to squeeze the most spl from these boxes from 40hz and up. Price is not a concern at all here. Cause of storage problems I can't build more of them, so I I'm just looking for the best of the best. Currently I've been looking at the pd 1850/2 and the eighteensound 18NLW9601. I'm wondering if you had any tips about what the absolute best driver out there would be for delivering massive spl.

Specs for the 2 drivers I've been looking at:

images6.thomann.de/pics/atg/atgdata/document/specs/237905.pdf

images6.thomann.de/pics/atg/atgdata/docu...ecs/169183_specs.pdf

Thanks in advance :)



Edit: I think maybe it is possible too squeeze in a 21 inch driver into the cubo. Do you think it would be possible to increase the maximum spl by doing so, and what would be the downside?
Posted: 4 weeks 16 hours ago by easy my youth #22062
easy my youth's Avatar
Thanxx for the help cubo - not to mention a quick response ! 30 metres throw is not bad at all, I was expecting less. Cubo sub is what I plan to build. Yes, I would more than welcome cubo 15 kick plans, a couple of questions : how high can it play, what 15s do you suggest . Have access to RCF, B&C, Emi, 18 Sound. PD, Void, Fane are super expensive here. Ferrite magnet is OK with me. So I would like to give it a try. Any phase or comb filtering issues when crossed to horn or reflex midtop. Thanxx again, easy my youth
Posted: 4 weeks 1 day ago by Cubo15 #22057
Cubo15's Avatar
The consensus is that Cubo's have the same "throw" as a reflex cabinet but louder, as you have used 18" reflex before I guess you know what to expect when used outside.
I've noticed that Cubo Sub throws a bit further. If one would say a Cubo 15 throw's up to 20 meter, than a Cubo Sub would throw up to 30 meters, whereas a scoop will throw 40 - 50 meter.

If cabinet size/portabilty isn't an issue, you could try Cubo Sub instead, that would also make sure you aren't missing any lower notes. The L18X451 is a great driver for sub duty and will work in Cubo 18 Extended and Cubo Sub equally well.

Do yo need plans for 15" kicks as well? I've been working on Cubo Kicks for quite some time now and I basically just need a few people tell me how great it is before I dare launching the plans officially. The benefit is that it's for 15" drivers, stacks and looks nicely with other Cubo's and is easy to build as well.

Best regards

Cubo
Posted: 1 month 14 hours ago by easy my youth #22053
easy my youth's Avatar
Greetings from Jamaica. I am rebuilding my sound and considering cubo 18 extended. I play roots reggae, cd and vinyl, strictly outdoor venues, 300-500 persons. Box portability and weight are not issues because I have storage, transport, and many helping hands. Ease of construction is important, no access to CNC, etc. I have used 18 scoops in the past but this time around will be mixing live music from time to time, so I am thinking cubo 18 extended using rcf lf18x451 driver. Comments suggest cubo 18 is indoor venue only. System is 18 sub to 15 kick , 12 mid, 1.5 compression driver. Any comments, questions, or suggestions welcomed. Give Thanxx, easy my youth
Posted: 1 month 3 weeks ago by Cubo15 #21976
Cubo15's Avatar
For the Lomax you can use a high pass at 35 Hz or higher. I suspect it to work best up to 100 Hz.

Best regards

Cubo
Posted: 1 month 3 weeks ago by haze #21974
haze's Avatar
Thank you very much for availability
probably I'm going to cubo extended because of the size
which hpf is recommended for this woofer? Keep 40hz or I can go a little low
Posted: 1 month 3 weeks ago by Cubo15 #21973
Cubo15's Avatar
The Peavey Lomax 18 will work best in Cubo 18 Extended, with the magnet in the horn (visible). The Lomax 18 will also work in Cubo Sub.

Best regards

Cubo
Posted: 2 months 3 days ago by haze #21952
haze's Avatar
i have some peavey lomax18 can they work?
fs 31,5
re 5,4
sd 0,118
bl 23,4
vas 294
mms 194
qms 11,15
qes 0,33
qts 0,386
xmax 10,2
1200 w cont.
Posted: 2 months 3 weeks ago by wahyudi #21901
wahyudi's Avatar
thanks, i like it.
Posted: 3 months 4 days ago by Koji Ohno #21863
Koji Ohno's Avatar
my lovely 4 cubo 18.. :side:
Posted: 3 months 1 week ago by Cubo15 #21839
Posted: 3 months 1 week ago by Vaibhavdj141996 #21838
Vaibhavdj141996's Avatar
what is the difference in Magnet facing out and in magnet in chamber of cubo 18? what is the advantage of magnet in chamber?
Posted: 3 months 2 weeks ago by Cubo15 #21822
Cubo15's Avatar
Cool, feedback is always welcome, as are pictures!

Best regards

Cubo
Posted: 3 months 3 weeks ago by don_caniball #21818
don_caniball's Avatar
thanks a lot , i´ll start with 4 pcs in next month i hope ! :) and when they´ll be completed and tested , i´ll give some feedback ! good luck :) and i am sorry for bad english i am from slovakia as i said before .