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Discussion Starter #1 (Edited)
... for frequency repsonse and spl in a 4 cu ft. sealed box (100% fiberglass fill) with a given budget of $160 and not wanting to go larger or ported/PR'd? Wouldn't room gain make it nearly flat to 20Hz? The 4 cu ft. figure is 5.7 cu. ft. minus 20% for the 100% fill and approx. .10 cu ft. for the driver. You think it takes up more than .10?

Power will be a PE BASH 500, which I already have.
How should I modify it for this combo?

 

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Discussion Starter #3
Does it model with as flat and as deep a response? I only want to do this once.
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Discussion Starter #4 (Edited)


Yellow is HF. Red is HO. That's a 15 Hz deeper extension and a flatter overall response. If this can beat for $160 without going bigger or ported/PR'd, while maintaining a Q of .7, someone please tell me :)
 

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I did a simulation, BassBoxPro says at 120liters (~4cu feet) F3=38.6Hz. Also at 500W reaching 115dB and cone displacement reaching Xmax at 22Hz.

Concerning the RSS315HF-4 it has higher Fs. 18 Hz for this one against 25 for the 12inch one fot just a few bugs more.
 

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Discussion Starter #6
Don't model is for 4 cu ft. Model it for 5 cu.ft. The 4 cu ft comes from subtracting 20% from 5 cu ft. for 100% stuffing.
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Discussion Starter #7
Here are all three Dayton RSS HF drivers (10, 12 and 15) compared for spl and freq. response with a Q of .7 in a sealed enclosure. I have the 10 now. The 12 wouldn't be much of an improvement, but the 15 certainly would!
 

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At 141 liters or 5cu foot BassBoxPro yields 38.3 Hz not much different from 38.6Hz. When i make it ridiculously large 20 or 40 foot it doesnt change anything for sealed. Ported is another matter..

What about porting it, at 5 cu foot it simulates F3 24.7Hz, and your Xmax at full power would be not easily reached in that smaller box? At 500W SPL is 116dB and cone displacement in range down to 14Hz
 

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Discussion Starter #9
I consider designing/building ported enclosures and designing proper amplification a hassle. No thanks. I wonder why WinISD and BassBoxPro yield such different modeling results? I'm using the parameters on the "downloadable WinISD files" section of this forum.
 

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You must consider the fill in order to get the true response. Your best investment would be a Behringer Feedback Destroyer with which you could shape the desired response.

Next would be a sub upgrade, but for this I suggest you save up for a Shiva-X at least. It's a much better driver than any of these.
 

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Discussion Starter #11
You must consider the fill in order to get the true response. Your best investment would be a Behringer Feedback Destroyer with which you could shape the desired response.

Next would be a sub upgrade, but for this I suggest you save up for a Shiva-X at least. It's a much better driver than any of these.
According to WinISD, the Shiva X2 loses to the 390HF at both F3 and SPL when shooting for Q of .7 in a sealed box. My wallet says it loses there too :)

Any others?
 

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According to WinISD, the Shiva X2 loses to the 390HF at both F3 and SPL when shooting for Q of .7 in a sealed box. My wallet says it loses there too :)

Any others?


Looks like the Shiva beats it in SPL and it's in a much smaller box too.

These are xmax limited models.
 

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Looks like the Shiva beats it in SPL and it's in a much smaller box too.

These are xmax limited models.

I'm unable to do any modeling due to computer issue. He will be using a 500 watt Bash amp as stated in the first post. Can you post a comparison with 500 watts input power and the appropriate HPF?
 

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Discussion Starter #14 (Edited)
Why are our graphs complete opposites? Maybe I'm doing something wrong? I'm opening the program, selecting the driver and leaving everything else as is (no adjustments), although I did change input from 1 watt to 500 watts for this graph. The program automatically selects closed box and Q of .7. It shows the Dayton going louder and deeper.

 

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Why are our graphs complete opposites? Maybe I'm doing something wrong? I'm opening the program, selecting the driver and leaving everything else as is (no adjustments), although I did change input from 1 watt to 500 watts for this graph. The program automatically selects closed box and Q of .7. It shows the Dayton going louder and deeper.

What your missing is the xmax, the point at which a sub starts bottoming out. As such the output is no longer useful beyond that point. This occurs at around 150 watts in a 10hz limitation check. For the Shiva it occurs at around 800 watts in it's box.

Good sealed sub candidates typically have very high Xmax's 20mm or greater. This allows them to be shaped by an EQ to the desired response. This is not the case with the Dayton which is at 14mm.

I'd also bet the Shiva has much higher sound quality. Though the Dayton Reference series is no slouch in that department, but there is more to sub or speaker than just pure SPL.
 

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I'm unable to do any modeling due to computer issue. He will be using a 500 watt Bash amp as stated in the first post. Can you post a comparison with 500 watts input power and the appropriate HPF?
This sub he's modeled is not suggested with a 500 watt bash amp even with the SSF he is going to be pushing the sub very hard(above xmax) from 35hz to 20hz. Plus in a sealed design there is no way he can get the F3 most folks want for a sub.

Do you know of any good $160 sub that can be sealed with great results? I just noticed that the Shiva price is a bit higher than it was. I'll see if I can't find something. This sub he's looking at just doesn't have the xmax to handle that kind of build. Unless this is a music oriented build?
 

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Isn't xmax already in the parameter file that I downloaded for both drivers?
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If you click the 2nd drop down you will see a choice for cone excursion it will show the modeled excursion and a redline with the xmax. You don't want to go above that and you really don't want to ride it to closely. Most subs are already going downhill in Sound Quality at that point. WinISD doesn't factor that in a model.
 

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Discussion Starter #19
Shouldn't the added surface area of the 15's cone make up for some of the difference in excursion?
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Shouldn't the added surface area of the 15's cone make up for some of the difference in excursion?
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It helps, but isn't as important as the material the cone is made out of and the quality of the attaching material. Just as you know that wooden bats hit balls further than a similarly sized foam bat.:whistling:
A better quality cone moves more air.
 
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