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Discussion Starter #1
Hey guys I'm geting ready to build two slot ported cabinets for the 18in mal-x sub. I was told by a friend that for best overall performance I should tune the sub to 16-18hz and the cabinet size should be 10cuft interior volume max after deducting the sub and braceing. This is with 1450 watts per sub.

So do you guys agree that this is the best size and tune to get the most out of the mal-x?

If not please post the tune and size of box and type of box that you have found to offer the best performance.

Thanks for any help. I'm hopeing my buddy has given me good info :dontknow:


Thanks Scott
 

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Discussion Starter #3
So your saying 8cuft box before driver and braceing being deducted and tuned to 12.5hz is the best size and tune for the mal-x.

I've looked through the thread and it seems the size and tune is all over the place. I was hopeing there was a best cuft cabinet size and best overall tune that this sub will perform best at? I really would not like to guess and instead hit the right size and tune off the bat.

Thanks Scott
 

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Well it really depends on how you listen to your system. If you use it mostly for movies then the lower the tune you can get the better but if you listen to more music then a higher tuned box or even a sealed box would be better. But when you go sealed you need much more power then ported or vented. For movies a tune to 12.5hz would be great and with that sub it would work great but maybe someone who owns that sub will chime in and give you some of their opinions.
 

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I don't have WinISD with me, but from what I remember, the Mal-x 18 is better suited in a 16-20ft box tuned around 14hz...The next biggest hurdle is how big your port should be, but somewhere around 65-75in² should work great.

In order to get that big of a port to fit in a 10ft² box would mean either a real long port (low 1st port resonance) or a higher than optimal tune.

Here's another thing to look at. Model your sub with 1450w and make sure it doesn't go much past xmax within the pass band. If it does, you either need to shrink box size, raise tuning, or don't "crank it to 11".
 

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Discussion Starter #6
So maybe my buddy is on the right track by recommending 18hz tune? I would say I'm 50/50 when it comes to movies and music. Music in the day time and movies at night.

I have a really large open room 60x35 so my friend thought going ported was the best way to go for some extra DB over sealed. At the beginning I was planeing on going sealed but was told because of my room size it would be best to go for the extra output that a ported box offers.

So if sealed is best for 50/50 maybe I should go with 4 mal-x subs in two sealed boxes over two ported? I have three subs so I would just need to buy one more and I already have the power.

Do you guys think thats the best way to go?

Thanks Scott
 

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10 cu.ft tuned to 18 hz works well, but as Looney pointed out so does going bigger and tuning lower. Here is 10.cu.ft. tuned to 18 hz compared to 18 cu.ft. tuned to 15 hz, both with 1450 watts input power. The bigger box will give you more low end output for movies in the 14 - 18 hz range. It all depends how much low end output you want. Decide how big of a box you want to go with and we'll figure out the porting.

Maelstrom 10-18.JPG
 

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RXP, using Mike P's models, the next thing to look at are excursion levels with 1450w. Do either cross xmax?

My thought on the whole box/power ratio, is get the driver close to it's limits (xmax or even a tad beyond) with the max power you will send it. For sealed enclosures that's super easy because all you do is change box size. For ported, you change box size and tuning points. If the box is too small you won't get as much output because you become amp limited. If the enclosure is too large, you become excursion limited and risk damaging the driver if you push it too hard.

Eventually you can balance everything out for your needs.
 

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RXP, using Mike P's models, the next thing to look at are excursion levels with 1450w. Do either cross xmax?

My thought on the whole box/power ratio, is get the driver close to it's limits (xmax or even a tad beyond) with the max power you will send it. For sealed enclosures that's super easy because all you do is change box size. For ported, you change box size and tuning points. If the box is too small you won't get as much output because you become amp limited. If the enclosure is too large, you become excursion limited and risk damaging the driver if you push it too hard.

Eventually you can balance everything out for your needs.
I am the one going to be building the box for RXPorlando. I been modeling and modeling some more depending on what he wants so i gotten a very good idea of where to go with box sizes and tuning. I am going to target around 17.0hz with 11cu ft after the bracing and port volume have been taken away. The sub will just be touching xmax at max input power. I think it should be the best balance for his needs of music and movies. I thought I was on the right track with relation to box sizes and tunning for optimal performance, now I am sure.


Just one question, when modeling a sub for a given enclosure size, I been subtracting the volume occupied by the bracers and port to get final box volume. Is this the right way to do it ? Does Win ISD account for port volume?
 

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Discussion Starter #14
Hey whats up danny. Hey guys what do you think about this. I'm stuck with 10cuft box up front with one sub tuned to 18hz. I'm thinking that when listneing to music I'll just use this sub and keep the back subs off and being space is not an issue maybe I'll have two strickly movie subs built in a large 18cuft box and tuned to 12.5:D

Is this a good idea mixing diffrent size boxes with diffrent tunes? Or is it best to stick with the same cuft box both front and back for best tuneing and performance?

It sounds like a good idea but I'm not sure if it will work well with rew or sound good?

Thanks Scott
 

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If you want to design different subs, one that will work awesome for movies and one that will work awesome for music, you really should spread the tuning points out on them. A purely for music sub would work well with a tuning of 25-30hz for the type of music I listen to. Most PA subs have an f3 of about 40hz so you could get away with even a 35hz tuning and an 18" pro style woofer. Then build a real large enclosure, tuned real deep for the Mal-x and cross them over with a DCX-2496.

Another thought (since you already have 3 M-x's) is just use multiple LLT's with the Mal-x; all of them being real big and tuned low. Sure, just one wont be as efficient or have as much output from 35-80hz like a higher tuned PA style, but you will have multiple subs covering the same area as opposed to one covering the deep bass and one covering the midbass.

Or, go with the in between design. 11ft tuned to the upper teens. You won't get crazy deep, but the 20-35hz output should be greater than the LLT.

Or, try...

Point is, there are a lot of options and I cannot give you a correct/best answer for your specific room and your needs.

If it were me, if I was putting them in a large room where size didn't matter and I'd not be moving them, I'd build really big boxes, tuned real low, and I'd have four of them. If I ever thought I'd have to move them around, I'd go sealed.
 
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