Large Room = Ported Sub: Rule or Rule of Thumb? - Page 2 - AVS Forum
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Old 03-20-2014, 05:48 AM
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It depends what sealed sub you are talking about. I'm sure dual SubM HPs would be more than adequate in most rooms. But if your talking about something like the SVS SB1000, 2 of those would get lost in a large room. Ported subs are generally preferred in larger rooms because you can get louder and lower while usually being a lil cheaper to get to the same spot within reason. That is because a sealed sub has a gradual frequency roll-off usually starting around 30hz, where a good ported sub will be generally be flat to around the tuning point then drop off very steep. So around the port tune a ported sub will have a several db advantage over a sealed sub of the same quality. Ported subs don't use too much room gain where sealed subs do and thats how you can get response into the single digits with room gain. But for a sub that starts to roll off at 30hz you want your rooms longest dimension to be short enough to produce room gain around 30hz which would be around 18ft for the longest room room dimension.

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Old 03-20-2014, 06:13 AM
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Originally Posted by JustABrah View Post

I thought in larger rooms dual sealed subs work great for home theater? Is that not true?
Read Post #5.

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Old 03-26-2014, 03:45 PM - Thread Starter
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Would anyone change their recommendation if I said these subs will be for 50/50, music and movies?

I find myself listening to music everyday before the wife gets home.

This is why we can't have nice things.
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Old 03-26-2014, 04:34 PM
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Would anyone change their recommendation if I said these subs will be for 50/50, music and movies?
I find myself listening to music everyday before the wife gets home.
Does that mean you don't care if they don't go low enough for HT when you do watch movies?

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Old 03-26-2014, 05:02 PM - Thread Starter
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Originally Posted by Bill Fitzmaurice View Post


Does that mean you don't care if they don't go low enough for HT when you do watch movies?


I would still like the subs play down to 20 Hz (maybe a little lower.)

 

When subs go that low, I don't know if you are giving up any desired musical qualities (punchyness, etc.) I know you give up peak output by tuning the system lower. But I don't think peak output will be an issue in my situation. I have a cheap-o 75W Yamaha sub (that I bought in college) corner-loaded and I'm quite surprised by how loud it will play.


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Old 03-26-2014, 08:24 PM
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When subs go that low, I don't know if you are giving up any desired musical qualities (punchyness, etc.) I know you give up peak output by tuning the system lower.
None of that is true.

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Old 03-27-2014, 06:23 AM
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Peak output can suffer if a sealed sub has to much bass boost applied trying to get more low output was my impression.

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Old 03-27-2014, 06:22 PM
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Quote:
Originally Posted by jchata2 View Post


I would still like the subs play down to 20 Hz (maybe a little lower.)

When subs go that low, I don't know if you are giving up any desired musical qualities (punchyness, etc.) I know you give up peak output by tuning the system lower. But I don't think peak output will be an issue in my situation. I have a cheap-o 75W Yamaha sub (that I bought in college) corner-loaded and I'm quite surprised by how loud it will play.


It would be best to stick with your Yamaha for now. You need to develop at least a basic understanding of subs; how they work, and room interactions. You also need to develop an actual set of requirements. For example: "(maybe a little lower.)" is not a useful requirement; punchiness is hard to match against the offerings of various suppliers.

When you understand why the advice offered in post #5 is valid then you will have a good start on planning your subwoofer investment.
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Old Today, 03:57 PM - Thread Starter
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Quote:
Originally Posted by Bill Fitzmaurice View Post
Quote:Originally Posted by jchata2 

When subs go that low, I don't know if you are giving up any desired musical qualities (punchyness, etc.) I know you give up peak output by tuning the system lower.

None of that is true.
The statement about losing efficiency for an increase in extension should have been clarified by saying that driver, wattage, and enclosure volume are kept the same. Speaking specifically to bass-reflex enclosures. Unless this article has led me wrong: http://www.hometheaterhifi.com/volum...ayporting.html

I have put this project on hold. For the time being, I purchased 2 BIC V1220s to hold me over.

Thanks again for everyone's help!

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Old Today, 07:24 PM
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Quote:
Originally Posted by jchata2 View Post
The statement about losing efficiency for an increase in extension should have been clarified by saying that driver, wattage, and enclosure volume are kept the same.
That is true, there's no such thing as a free lunch. If you want to extend response lower without sacrificing sensitivity then the box must be made larger.

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