Cubo Sub

Hey guys, first time post.. I will be building 4 Cubo Sub's and wanted to know if Cubo or anyone else would recommend an Eminence driver for the sub.....
Thanks

Hi guys! I currently have 3 Cubo18 extended subs, loaded with Eminence Sigma Pro 2 drivers. They are excellent and sound lovely but I've gotten greedy and want a similar 'sound' but a little lower reach (I can't run a crew/soundsystem titled 30Hz and not get near enough to it!). My question is will the Eminence Sigma Pro 2 18" drivers go lower in a cubo sub, or would I be better off replacing them with something like the RCF LF18X401 which in my mind seems like a slightly more expensive, but decent alternative? I want to get as close to 30Hz as I can, without having anything too big, and also something that 'fits' the rest of my system.
As always, many thanks for any advice!
Edd

To both you guys:

That depends on where you're located, prices in Europe for example don't generally favour Eminence, prices in the USA do.
You can basically use any 18" Eminence driver in Cubo Sub but most Eminence 18" drivers are designed more as bass driver and less as sub drivers, so I wouldn't truly recommend them.

From all the 18" models Eminence has, personally I would only consider the Impero 18C, even though it's a bit on the light side (Mms).
The Definimax scores better in that department but has a rather low Xmech, less than 32 mm p-p for a 18" sub driver is a tad on the low side for me (for a bass driver that's generally plenty). The Impero 18A has a lower EBP as the 18C and I personally prefer higher EBP drivers in Cubo designs.

As clear as most Eminence 18" drivers are designed for bass, the RCF LF18X401 is designed as a sub driver. Even though it's parameters suggest it wouldn't mind a bass cabinet either, it's really one or one and a half step beyond the Sigma Pro when it comes to sub performance.
If you would have to buy either the Sigma Pro or the LF18X401 for Cubo Sub, that would be no contest. Considering you already have the Sigma Pro, it would survive Cubo Sub but the RCF would rule it.

Best regards

Cubo

Thanks for the advice, I think RCF loaded Cubo Subs are now on the cards!

Hello Cubo,

I have built the 21" version of your cubo design loaded with a Precision Devices ET211S driver. Problem is this used to be a heavyweight driver (weighing in at over 30kg) but it is only 750w rms, 1500w max.

We were thinking about upgrading to the RCF LF21X451 rated at 2000w which would be powered by a Crown CA12 amp in bridge mode. What are your thoughts on that?

Also, how important are the side braces - thin strips on the side by the mouth - or are they more for attaching a grill? Just worried about pumping 2000w through the cab and it falling apart...

Finally, I was wanting to use this outside and was wondering whether I could add some sort of 'extension' (barn-door) like attachment to the front to help with the throw or the bass - something like the mouth of this speaker attached to the front of the cubo sub? Crazy or no...

Thanks in advance,

Thomas.

edit: meant to say 'throw of the bass' and also to attach a link to the speaker I was referring to:

users.skynet.be/fa567915/IMG_8823.JPG

Thanks again.

I am in the US and looking for and looking to spend $250-$350 per sub driver, what would you recommend then for the cubic sub???

The Fane Colossus XB is a great fit at 299 a driver.

@ space141:

What are your thoughts on that?

Perfect match.

Also, how important are the side braces

The more power you put through it, the more important the bracing becomes. It isn't just for the grill and at 2000 Watts, I'd say it's mandatory. Besides, if you place the grill firmly with bolts, it will form a wall-to-wall bracing that reinforces the sides and mouth panel even further (tho you would be fine without up to 1500 - 2000 Watts.

Finally, I was wanting to use this outside and was wondering whether I could add some sort of 'extension' (barn-door) like attachment to the front to help with the throw or the bass

Extensions on hybrids and tapped horns give more output in the low end but excursion will raise to do so. I would recommend a slightly faster flare rate as the last segment (the baffle) of the Cubo Sub.

@kriptech:

Good sub drivers: www.usspeaker.com/eighteensound-18LW1400-1.htm and neo: www.usspeaker.com/B&C-18nw100-1.htm

Great sub drivers: www.usspeaker.com/B&C-18TBW100-1.htm and www.usspeaker.com/beyma%2018PWB1000fe-1.htm

The 18XB will pronounce the lower kick around 80 Hz a bit more, while the "great sub drivers" will emphasize below 50 Hz, the good sub drivers in-between.

Best regards

Cubo

Before i buy my first 21NLW9601 i just wanna make sure its a better choice than the 21NLW9001 for a Cubo Sub with the magnet sticking out like on the plans.

I know they are both very high end 21" drivers and the 9601 seems to be the more advanced of the two, but he reason i ask is because i read a post by someone over at speaker plans saying that Cubo designs actually act like reflex boxs in the lower bass notes, and i dont know much about this stuff but i also know that the cubo has too short a horn length to play the bass notes under normal horn theory but still does play those notes, so id love to hear your thoughts on this if you have the time?

The reason i ask is because the 9601 is claimed on the 18sound site to be suitable for horn loaded or bandpass cabs, and the 9001 suitable for vented enclosures, so in relation to what i said before it made me think the 9001 *may* be better for deep bass (if the cubo does act like a reflex for low bass).

You did tell me that the 21NLW9601 will be a good choice for deep bass and i am very inclined to believe you that it will work, i just want to make sure im making a better choice than going with the 21NLW9001 instead, it will make me feel alot better when i take the plunge soon haha, these drivers aint cheap



EDIT:

RIght, ive been doing abit of research and read over at SP that you consider the Cubo Sub to a form of 6th order bandpass (18sound say 9601 is suitable for bandpass), and also you prefer a high EBP, worked out that-

9601 EBP: 128

9001 EBP: 89

(rounded from 1 decimal place).


This is making me think the 9601 is the better choice thus far