New diy sub

[Mike P.]

I take it that graph is based on 4 FI's or AE 15's against 2 18" maelstroms.

Yes.

If theres doesn't seem alot in it

I don't know what you mean.

What would your advice be to go for.

A pair of Maelstroms. They provide more then enough SPL.

How would the FI Q18's dual opposite configuration compare to the dual 18" maelstrom's. Would you be able to show me them together please.

[sub_junkie]

I agree with Mike P. I can't imagine how loud that will be. Plus, wouldn't the dual Mal-X's be cheaper than four 15's? Or, if you want to, and have about $400 extra over the dual Mal-X's, you could always go for dual Maelstrom-21"'s That would move some serious air...but about $600 each...
But, I don't know near as much as Mike, so what do you think??

[gperkins_1973]

mike,

thanks for doing that. The maelstrom looks about 6db better at 10hz. Would you say the maelstrom is better than the FI Q18. There is a company in sweden thats sells the maelstrom gen 2's for £400 each or I can get the FI Q18's for £350. Is it worth spending the extra.

Are there any brands of 18's that would do a better job.

What subwoofer are going to be the best for my box and just out of interest what is the correct size enclosure for the 2 18" maelstrom's to get the best out of them.

I came up with the dimensions of 36" long by 24" wide by 30" high as it fits in the corner.

cheers for all your help Mike.

cheers graham

[gperkins_1973]

Dual 21"s!

Its a shame Exodus dont ship to the UK as the 18" maelstroms are $395.

cheers graham

[Mike P.]

The Maelstrom has more low end output and is definitely worth the extra £50. 2 Maelstroms in 12 cu. ft is perfect, with a 20 cu. ft. box you would gain 1 db at 20 hz and give up 3 db from 30 hz on up.

[gperkins_1973]

Mike

I am going to make a scaled down model this afternoon. I will upload it when it is done so you can let me know your thoughts. Getting very excited now. Wood wise is it better to use 0.75" or 1" thick mdf and should I double up the sides of the box as I need to double up the front and back to fit the drivers in.

Also should I use 0.75" or 1" thick mdf for the braces. I will probably go with 3 braces along the width at 9" gaps but what about the brace going long ways. Do I really need that. It's going to be a bit tricky to build it into the other braces.

cheers

Graham

[gperkins_1973]

One thing I have noticed with the Maestroms is that anything over 2500 watts power based on the dual 18's in a sealed box takes the cone excursion on the max at 5hz. The behringer 4000 is rated at 2 x 2000 watts rms in 2 ohms. When you apply all the power to the drivers it the excursion max is 18hz. I know the maestroms are 1500 watts rms so surely they should handle 2 x 1500 watts rms no problem.

Can someone explain to me if I should worry about over driving the drivers at loud volumes when playing very low frequencies.

When you have 4 FI Q15's the lower frequencies are not as good as the maestroms but based on the power of 2 x 2000 watts rms you never reach the max excursion on the 4 drivers at max input of the amp.

The FI Q15's are about 2db down on the maelstroms at 10hz, about the same at 20hz but 2db more over 50hz.

Is it worth going 4 drivers for 2db and extra cost or will I have no problems running the maelstroms full power.

cheers
graham

[Mike P.]

0.75" is fine for the sides and bracing. The brace going the long way cam be eliminated since the baffle panels are 2 x 0.75". It wouldn't hurt to glue in a support from above the sub to the first brace and from the bottom of the sub to the first brace.

or will I have no problems running the maelstroms full power.

The difference between the power input that causes Xmax at 5 hz and the power input that causes Xmax at 18 hz is 1 db at 20 hz. If the sub should bootom out at the extreme levels you're talking about, just turn it down a bit. You won't notice the SPL difference.

[gperkins_1973]

Mike,

I have watched Ironman at -7db MV on the onkyo with the PB13 so the new dual maestrom'sl should breeze through that. Is that correct. How would I connect the amp to the behringer, then from the behringer to the sub.

cheers

Graham

[Mike P.]

The proper order would be Reciever - Behringer - Amp - Sub.

[gperkins_1973]

Mike

Sorry confused.


Reciever - Behringer - Amp - Sub


Onkyo 876 - behringer - ? - sub

cheers

Graham

[Mike P.]

I'm the one who's confused. When you said Behringer I thought you meant the Behringer BFD. I got 2 threads mixed up. Sorry about that.

[gperkins_1973]

Mike

Sorry its probably me not explaining myself.

Onkyo - Behringer Europower 4000 - Sub

What cables do I need to connect the three up and how.

Also what EQ do I get: BFD or Anti-mode.

Do I connect the EQ between the Onkyo and the Behringer amp.

cheers

Graham

[gperkins_1973]

Mike,

I have just been reading about passive radiators in subs instead of using ports. How would my sub compare if I had a cube with passive radiators. Would it be better in the low end and how would it compare 30hz upwards. I did try to add passive radiators on winISD but I found it confusing.

I just found this driver on this site: http://aespeakers.com/shop/catalog/p...products_id=71

I tried entering the parameters but I couldn't figure it out. They also do 18" passive radiators too so don't know how two 18" drivers and two passive radiators in a 24" cube box would fair against my dual 18" maelstroms sealed. Your advice would be appreciated.

cheers

Graham

[Mike P.]

The Onkyo has a single RCA output for the LFE. That connects to the two 1/4" inputs on the EP4000. You'll need a Y adapter with a single male RCA on one end and two 1/4" male plugs on the other end. Then you run speaker wire from each output om the amp to each sub. I use 10 guage wire. Download the manual for the EP4000 and have a look at the back panel. The inputs you will use are #8 and the outputs are #12.

http://www.behringer.com/EN/download...P0A38_M_EN.pdf

Regarding PR's, they will produce more low end compared to a sealed sub, but it requires 2 PR's for every sub. You would need 4.

[gperkins_1973]

Mike,

I just put a thread on the soundsplitter with regards to the RL p18's. Let me know how these compare with the maelstroms. They are £150 cheaper and have slightly more spl than the maelstroms.

cheers

Graham

[Mike P.]

RL p18's are not available at the moment.

[gperkins_1973]

Bummer, that leaves FI Q18's and Maelstroms then. What do you think. Shame about the soundsplitters and they had a really good graph on WinISD.

cheers
graham

[Mike P.]

Maelstroms will give you more bottom end in this setup.

[gperkins_1973]

Mike,

Below is a link that the guy from FI over here sent me showing that you can run 2 DVC 2 0hm subs in series to get a 2 ohm load.

http://www.the12volt.com/caraudio/wo...s.asp?Q=2&I=22

Have a look and let me know your thoughts.

Also I have attached my sketchup drawing I have made of my sub. Phew! took some getting used to but I got there.
Let me know what you think of that.

cheers

Graham

[Mike P.]

You can't run the EP4000 in bridged mode with a 2 ohm load.

The box design looks good..

[gperkins_1973]

Mike,

Ive attached the link to the behringer 4000 amp. It looks like you can run it 4000 watts rms bridge into 4 ohms.

Would it be possible with two 2 ohm DVC subs to do this or would I still have to get D4 subs.

http://www.behringer.com/EN/Products/EP4000.aspx


cheers

Graham

[Mike P.]

You need D4 subs as previously stated.

[gperkins_1973]

Mike,

This is becoming a nightmare. I don't think I have seen many subs that are D4.

Would it work if I got a D1 sub?
FI do the Q's in D1 configuration.

cheers

Graham

[dradius]

Not sure if it is something you'd want to consider, but you can get the ED 19ov.2 in either D2 or D4