Cubo 18

Bass driver

The Beyma has " bass driver" written all over it, so it's a very good match for both Cubo 18 Standard and Extended.

The difference in sensitivty between Cubo 15 and Cubo 18 isn't that much and can vary dependant on the drivers used. An 18" does have more air to move for the same excursion, so that can be an advantage in the lowest end bit of the response.
There is of course usually a difference in tonality between 15" and 18" drivers and you'll be more likely to find a 15" sound good above 100 - 110 Hz then a 18" driver (imo that goes for Cubo's and reflex cabinets all the same).

Now your not going the extremely high power route here but there's some high power 18" drivers out there that can really set the difference between a Cubo 15 and Cubo 18.

Guitar driver

The K151 is a good driver for both Cubo 18 Standard and Extended, it's really ment as a guitar speaker and I know about people using Cubo's as bottom end for their guitars, so all good there.

The no-crossover-part doesn't sound to good to me to be honest. I think at least a low pass for the Cubo 18 should be in order. It's a form of folded horn so it's bound to sound bad somewhere in the 100 - 300 Hz region.

Now the 10 inchers and the Cubo 18 might sound OK in the overlapping area but it might like some processing. It's hard to tell, easy to hear.

Best regards

Cubo

OK, thanks for the reply, sounds like my K151 might be better in a reflex box, I have a 100 Litre ex 15" box and will port it to 32Hz, see how that goes with the 10's. I notice lots of bass players use only boxs loaded with multiple 10" speakers, is it because the big 18s are to slow in response?

Thanks for Reply Cubo, but now i have more and more doubts...

Reading the 18P80 and 18LW1400 especifications, i notice that the VAS in 18P80 is 415l Vs 297l in the 18LW1400.
Do you think it could be a problem?

Anyway the price between this two drivers is similar, u think i could really notice a big the difference?
The Xmax in 18LW1400 is bigger and even need less VAS than the than the 18P80 so now im confused…

And the last question, Can i find in any place the difference between cubo 18 and cubo18 extended?

THanks for all CUBO!

Hi Cubo, i have more ideas,

I will build the CUBO in order to finish my unversity studies like Sound engineer in Spain, so now im thinking about to build a cubo 18 with the magnet inside study the frecuency response in an annecoic room and then in the same cab move the magnet outside and then study again the freq response in order to compare both.

U think is posible to move the driver without to make a new cab?

We have a lot of equipment and really good annecoic room in the university so i can use it to study lot of parameters about cubo if u are intrested now i only thought about to change the magnet but maybe you have more in your head...

sounds like my K151 might be better in a reflex box

If you're going the no-crossover-route, I don't think it matters that much. An 18" in a reflex is bound to loose it's touch at sounding right as well and is not filtered like a Cubo (the Cubo adds an extra 24 dB/ octave filter like a bandpass would). Still, your choice.

I notice lots of bass players use only boxs loaded with multiple 10" speakers, is it because the big 18s are to slow in response?

Technically an 18" has most potential to play low and a small coiled 10" has most potential to have the best transient response. But technically it's also possible to create an 18" with better transient response and a 10" with better low frequency performance.
Then there is the basic human conception, that large drivers play lower and small drivers are "faster". Then there is the marketing departement.

Mix these variables together and add some other variables and you'll have the perfect explanation why 4 x 10" is so popular.

Tuning a 4 x 10" to 30-ish Hz is usable when the 10" have a resonance frequency in that area or when you want to add extra distortion by tuning way below a drivers tuning frequency, it doesn't actually mean the 4 x 10" will play effectively down to 30 Hz. It will likely create a large gap between the output at 30 Hz and where ever the 10" start to become effective.

Reading the 18P80 and 18LW1400 especifications, i notice that the VAS in 18P80 is 415l Vs 297l in the 18LW1400.
Do you think it could be a problem?

I always include Vas into my advise, so no, I don't think so.

Anyway the price between this two drivers is similar, u think i could really notice a big the difference?
The Xmax in 18LW1400 is bigger and even need less VAS than the than the 18P80 so now im confused…

I think you're confused because Vas is not what you think it is, could be wrong though. Also you seem to over emphasize the importance of a single parameter. It's the combination of the parameters as a whole that dictates performance.

Anyway the 18LW1400 is more of a sub driver, the 18P80nd is more of a bass driver. Cubo 18 is primairly a bass cabinet so the 18P80nd makes sence. And you would aspect perhaps a slightly higher crossover point using the 18P80nd.

And the last question, Can i find in any place the difference between cubo 18 and cubo18 extended?

The plans from both would be my best bet, I mean if you look long enough at the pictures you're bound to see the difference. If you mean what that difference constitutes to I would advise this forum, in one of the main Cubo threads (Cubo 15, Cubo 18) as the question has been asked a quazilion times

As for experimental deviations: Well perhaps closing of the horn mouth and adding some resonant pipes to see if you can bring the f10 down to 30 - 35 Hz. If the Cubo model under test can be modified I would increase the rear chambers volume to the same end.

U think is posible to move the driver without to make a new cab?

Yes??

Best regards

Cubo

I assume you're using t-nuts and bolts??

Best regards

Cubo

Hi cubo, i can get a p-audio e-18elf for cheap. How is it different compared to the c-18 elf mentioned recently? Cubo sub suitable?

Thanks for all Cubo!! i will let u know in a few days how is going all!!

Thanks!

The e-18elf weights about 2 kg less than the c-18elf. Parameter wise it's good but it's a bit on the light side for a sub driver making it a borderline case.

Best regards

Cubo

Hi Im looking for phase plot for cubo18. Who can help me?
And second, I think about strange driver:
stx.pl/sw-stx-18-4-1300-8-f-s-mc.html
Someone can tell me more about?
L parameter isint to much??
Regards