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In the Forum: Horn-Loaded Speakers
In the Thread: Jessie Dazzle Project
Post Subject: Ratio of diaphragm area to throatPosted by jessie.dazzle on: 8/5/2007
Hello guy,
Regarding your question : "...What ratio of diaphragm area to throat area did you arrive at (for the large horn) & how did you choose it?..."
The ratio I used for the 45Hz horn is about 65% of the ø of the diaphragm LESS THE SUSPENSION.
ø of diaphragm less suspension (AK151) : 11.25 inches
ø throat (45Hz horn in the illustrations) : 7 inches
Ratio : 65%
I arrived at this ratio via the following logic : This is a Bass horn, and it needs to be long to be effective... I will be using it down to about 60Hz ; a 60Hz wave measures about 18 ft long... I targeted a half wavelength dimension at 55Hz. I also looked at other horns which don't simply use the diameter of the driver as a throat diameter (taking info from actual horns in a local audio shop and also from various postings on the web).
If you take Romy's Upper-Bass horn for example :
ø of diaphragm less suspension (Fane 8M) : 6 inches
ø throat : 4 inches
Ratio : 65%
Nothing left to do but try it and hope for the best...
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