the Qd value for the alpha 10 in the pialign data base that comes with the software is 2 but according tot he emminence website qts is .59 for the alpha 10 and the Qd should be 1/.59 = 1.69. When I plug in 1.69 into pialign I get a slightly bigger enclosure that the one in the 2pi design.
Why use a different QTS than what is provided in the emminence spec sheet?
Wayne Parham Messages: 18786 Registered: January 2001
Illuminati (33rd Degree)
Eminence is constantly changing specs and that figure was for an earlier model with slightly different values. I've noticed most times when they do that the parameters are compatible, in that the new driver specs work well in a cabinet designed for an earlier model, not excessively underdamped or anything like that.
Wayne Parham Messages: 18786 Registered: January 2001
Illuminati (33rd Degree)
For a woofer like the one you've described (with Qts~0.38), PiAlign generates a recommendation that results in a very good response curve. Woofers with very high Qts values tend towards underdamped response and those with very low Q make slightly overdamped systems. You're is right in the middle so the response curve will be nice and flat. But PiAlign favors small cabinets and you can increase cabinet size and get deeper extension.
Woofers work well in a range of cabinet volumes. For example, I'd expect the woofer you've described to work very well in cabinets from 0.5ft3 to 2.0ft3 tuned to 25-30Hz. If you're going for a full-range speaker with a wide-bandwidth woofer, something like a small two-way speaker, then I'd go with the PiAlign suggestion. But if you are going for a sub, I'd look at alignments that use larger cabinets to get deeper response.
Posting Rules
Members
Search
Help
Register
Login
Get a T-Shirt!
