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Sonnie. I don't want you to worry too much if you end up with a system that does not exactly give you 4 or 8 ohm. There won't be a huge difference between different loads (as opposed to what you might think) The EP 2500 power at 4 ohm is ~ power at 8 ohm.
 

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Discussion Starter #22
If I bridge it 4 ohms... I get about 1950 watts. At 8 ohms bridged... it is about 1330 watts, still good power, just not taking advantage of all of its power.
 

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Figure another 8-9dB from teh 15s, plus roomgain, and you're looking at serious structural damage to you house, Sonnie. You are aware you can reach reference outdoors with that setup? ;) Pretty over the top! :T
 

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If I bridge it 4 ohms... I get about 1950 watts. At 8 ohms bridged... it is about 1330 watts, still good power, just not taking advantage of all of its power.
Is it based on specs or measured? The TA-2400 Amp will have quite similar power at 8, 4 or 2 ohm load....
 

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Discussion Starter #29
This is actually for two drivers in one enclosure.

I am having a brain lapse... :ponder: Is that port length for both ports combined or each port?
 

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This is actually for two drivers in one enclosure.

I am having a brain lapse... :ponder: Is that port length for both ports combined or each port?
Each. I knew it was 2 in one. I was thinking you could go to around 46-48ft total for the 2 and reduce the port length a bit. It's gonna be a Haus regardless. (I just edited my response right into your post on accident. Oops. Thought I hit the quote button.)
 

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Discussion Starter #31
Yep... I looked at even 50ft^3 with 2 x 8" ports at 32" length each. It looks good too.
 

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Nice :bigsmile:

Dual 6 ohm in series is 3 ohms - I'd do that and call it a day. It's not going to make a significant difference. I would strongly reconsider using just one amp though. With your Ebay know how I'm sure you can pick up another EP2500 extremely cheap :T

Unless the parameters changed, my modeling doesn't look like yours Sonnie. I'm looking at 50 cubes and two 8" ports that are 30" long each and I have a more pronounced low end. Are you using any filtering?

P.S. Sealed schmealed. Go for the gusto!
 

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Discussion Starter #33
Kevin stated the Maelstroms I will be getting are dual 2 ohms... so I will either have to go with stereo 4 ohm or bridged 8 ohm.

Yes... I am using a 10Hz HPF in my modeling.

I think what I did was round the ports off to 32" and it changed the tune just a little bit from 12 Hz.

Here's the back wall plan...



These will be in a LLT manifold... ported out the front of the riser. Sitting on top of each driver cabinet is an EP2500. :flex:
 

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Discussion Starter #36
Yeah... the second amp is a done deal. I may even do 21's if Kevin has them ready by then.

I think I will ease on up to about 15Hz. My AudioPulse 15's are at about 17Hz.

It appears 15Hz will require a pair of 18" ports 8" diameter in a 50ft^3 area.
 

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With that kind of space, why stop at two and not 4 MalXs sealed in 120cuft with one amp at 2k? Bucks saved on amp better used on drivers IMO considering volume allowment. Usable response below 10khz seems like value in sealed vs ported to me. Here's a graph or two

CB Response Maelstrom 18.gif

CB Excursion Maelstrom 18.gif

Room gain should help a bit below 20hz. This would be pretty scary with WOTW.
 

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Nice curve for sure!
 

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Discussion Starter #39
I actually have 150ft^3 to work with... maybe even a little more. This is not 4 times VAS of the drivers combined, much less 10 times VAS. However, it does still look pretty good.

Here's what I come up with for comparison...





I think the question would be where will I gain the most for the most usable response range?
 

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Measurements have shown as much as 6db or more in room gain below 20hz..it seems the lower you go, the greater the gain and the energy stored. I wouldn't be surprised if you picked up as much gain as needed where the ported alignment is more prodigious. The real sweetener is the stuff below 12hz, where your bowels kinda begin to twist a bit. A fellow AVS member posted a remastered copy of the early Titan missile program launches with heavy 5-10hz content. I'm actually afraid to try it out in the HT. My den system with dual 15's protested a bit but they don't go below 20hz anyway. If you're interested, i'll Email it to you...may help you make your decision on alignments.LOL
 
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