Cubo 15

Are the dimensions of the bracing arbitrary or where do I look them up then?

If you look at the cut list and plan it shows where the brcing goes there are also plenty build pics.

The sizes are very easy to work out. The only slight snag is when fitting the side bracing at the end of the horn mouth. I left them to last they are the same angle as the driver mount panel I think?

The rear bracing is clearly shown in the cut list. If you want some pics let me know and I can send them to you but you will find them earlier in this thread.

happy building.

@Jay: Mounting the driver with the magnet inside the chamber (not visible from the outside) will result in the effects you describe.

@Sam: Best is to use a high pass and low pass for the Cubo's. As the Delta Pro's don't have a large Xmax or large VC, a high pass will protect the drivers both electrically and mechanically (up to a point off course). To keep it cheap you could run the Cubo's in mono and the tops stereo (unless you're working on a single amp), as there isn't a lot if any stereo information within the bandwith of the Cubo's anyway. Or fiond a amplifier or crossover with a decent high pass.

@Jim: The dimensions of the bracings are shown on both the Construction Drawning and the Cut sheet (a 41 x 41 cm sheet with 3 triangles shown inside).

@CP: The dimensions of the side bracings near the horn mouth can slightly change dependant on how thick the grill and/or acoustic foam iis that some like to use.

Best regards

Cubo

Awesome Thanks cubo, reckon i will get an external active crossover then so i can change things around a bit Cheers

thanks Cubo

Thanks again MR C. as usual your answers are extremly informative.

I knew that the dimmensions of the triangle bracings were there I just could not remember if the horn mouth bracing sizes were shown.

BTW the bracing that goes above the horn mouth inside the chamber would you advise people to postion them against the sides or have them placed around 100mm from either side or should it be only one piece in the centre?

I still think this design is oustanding and thank you once more for sharing it.

Actually looking at active crossovers its gonna be alot of hassle getting another amp just to power subs... Anyone know where to buy a good passive crossover to use with delta pro 15s with a high pass output to go to satellite speakers (or another high pass to add to it)?
I was looking at just buying a replacement crossover for say a peavey pro sub as they have built in high pass outs for satellites, but not sure if they will do the job. Thanks in advance for any help
Sam

@Sam try parts express

Cubo- regarding my question about EVM 15, how high can I go? Looking for kick above mth30

BTW the bracing that goes above the horn mouth inside the chamber would you advise people to postion them against the sides or have them placed around 100mm from either side or should it be only one piece in the centre?

They're intended to go each on 1/3 of the internal width, just as the two smaller triangular bracings.

@Mooreman: What Peavey subs are you talking about, it should be easy to determine whether they're are viable or not.

The thing about passive crossovers is that they're dissipating amplifier power as heat (almost halve of the amplifier power is lost as extra heat), that is why, for the price of a good single passive crossover you can usually buy an stereo active crossover, with additional high pass. A high pass can take out very low frequencies that are often quite power consuming, whilst they do not add to the overall output (ussually the opposite is true).

An active 1000 W setup will likely be just as loud (and potentially sound better) as an passive 2000 W setup, but we all got to start somewhere, just keep it in mind.

If the impedances match you could also go mono (but keep it quit).

Cubo- regarding my question about EVM 15, how high can I go? Looking for kick above mth30

To be honest, I do not think a Cubo 15 will sound good over 125 Hz, so it's not a really good kick above the MTH-30. It also does an extra 5 Hz deeper bass as an MTH-30.

I couldn't recollect the T/S-parameters for the EVM, do you have any. Perhaps there are more suitable options to be found.

Best regards

Cubo

hey everybody...

got in touch with cubo a couple days ago and looks like i will be building an extended cubo15 for the Dayton Audio PA380-8 15" Pro Woofer. should be delivered on friday. hope i can get started on friday too. ill keep you guys updated and will upload pics as i go.


Specifications: • Power handling: 500 watts RMS/1,000 watts continuous program • VCdia: 3" • Le: 3.38 mH • Impedance: 8 ohms • Re: 5.8 ohms • Frequency response: 28-3,500 Hz • Fs: 28.3 Hz • SPL: 98.5 dB 2.83V/1m • Vas: 8.85 cu. ft. • Qms: 9.99 • Qes: 0.23 • Qts: 0.24 • Xmax: 5.0 mm • Dimensions: A: 15-1/8", B: 14", C: 6-3/4"

www.parts-express.com/pdf/295-034s.pdf