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PostPosted: October 20th, 2020, 10:31 pm 
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Assuming reflex box design was properly done, what is the expected changes in bass response in going from no fill to over-filling the box


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PostPosted: October 20th, 2020, 10:50 pm 
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Pelliott321 wrote:
Assuming reflex box design was properly done, what is the expected changes in bass response in going from no fill to over-filling the box


I guess my question would be -- why over-fill?

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PostPosted: October 20th, 2020, 11:15 pm 
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It is equivalent to increasing the size of the box. How much depends on how much fill and what kind of fill you use.


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PostPosted: October 21st, 2020, 7:18 am 
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Using fill inside a box only increases the virtual volume to a point. If you overfill you will begin to decrease the available volume. That will raise the Fb and increase Qts, the reverse of what you want.


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PostPosted: October 21st, 2020, 8:55 am 
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What I am asking is what will I be hearing as I go from empty to over fill.
What is actually happening as one adds the fill. What happens to the woofers curve


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PostPosted: October 21st, 2020, 9:16 am 
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It is my understanding that a bass reflex cabinet does not have filling, just material on the walls to dampen reflections. Sealed box designs use fill.

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PostPosted: October 21st, 2020, 9:58 am 
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Thanks, Dave
Any guess what effect in adding fill to a bass-reflex would have.
What is the sound of an overdamped woofer in a bass-reflex cabinet


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PostPosted: October 21st, 2020, 10:09 am 
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Based on my limited knowledge of all this you don't want to put fill into a bass reflex cabinet. I suppose if you've screwed up the driver/cabinet volume/port dimensions you may be able to make improvements with fill, but I don't really know.

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PostPosted: October 21st, 2020, 11:19 am 
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Pelliott321 wrote:
Thanks, Dave
Any guess what effect in adding fill to a bass-reflex would have.
What is the sound of an overdamped woofer in a bass-reflex cabinet

The woofers were made selectively more rigid by saturating a square-shaped woofer cone area with a polymer otherwise known as Varathane® along with a lowered fee-air resonance by virtue of an additional 30 grams of weight added to the woofer perimeter. Additionally, the empty cavity under the dust cap was treated with acoustic fill to eliminate that detail-smearing cavity resonance. That helped the upper mid-range performance and integration with the horn. Also, the cabinets were tuned with the end result of minimum box coloration, a neutral mid-range, and detailed bass performance. Part of that scheme was the addition of a 2-inch thick baffle to lengthen the path from the woofer to the vents on either side of the horn. I ended up with what I call a “half-ass” transmission line as opposed to the original vented-reflex design. Overall the speakers went from lower response of about 45-Hz. to 31-Hz. Bass and the lower mid-range tightened up dramatically. Those of you that have been here have heard the end result.


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PostPosted: October 21st, 2020, 11:33 am 
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so the answer is maybe


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