[WerTicus]

Hello people I was recently pondering (yes I have been told to be careful not to hurt myself)  And i was wondering how much head room one would leave their mid range speaker so as to make sure its not operating within the breakup region....

Is there a away to calculate its breakup from any of the figures?

I ask this after I notice one 6.5" scan speak speaker going up to 4000hz and a revelator 6.5" scan speak going up to 5000hz obviously a significantly higher frequency.  But perhaps one would be missing something by using 6.5" and perhaps one should be using a 5.5" instead or 4"?  One wouldnt want to miss the details, even if the tweeter came online at 2.5k?

[_scotty_]

WerTicus, You are asking a generalized question about driver cone breakup, bell modes and comb filtering. Here is a link to a glossery of terms with definitions http://www.webervst.com/spterm.html#comb,bear in mind that this site deals with musical instrument speakers and applications. The explanations are still good. A speaker with perfect pistonic behavior is the goal. No cone breakup, bell modes, or comb filtering resulting from the first two conditions. Your question can only be answered in specific instances because every speaker cone will behave differently due to its shape and materials used in construction.  Pick some specific Scan-Speak drivers from this website,mid- woofers and tweeters,   http://www.d-s-t.com/scs/index.htm see if you can pick out the best crossover frequency
based on a goal of flat frequecy response. Bear in that mind as the frequency increases the wavelength gets shorter,when the wavelength
equals the emissive diameter of the cone the drivers dispersion will start  to become very narrow like a flashlight beam. Ideally you would like to crossover before this happens to a significant extent. the mathematical formula for calculating the wavelength of a specific frequency is 1100ft./sec divided by the frequency in Hz times Ft. Example, wavelength of 20Hz. 1100/20=55  55x12in.=660in.or 55ft for the wavelength at 20Hz
2nd example,1100/20,000Hz=.055ft, .055ft.x12in.=.66in. for a wavelength
of 20,000Hz.    Have fun, Scotty