I can smell the can of worms that just opened in this thread : )
My personal thoughts are that 100 Hz is too low for a driver expected to cover the entire upper midrange region. I also agree with Trelja's comments that optimal woofer crossovers are quite low. What to do?
Well, if you use a "filler" driver aka a "upper bass /lower midrange" driver to fill in the gap, you've now got more dispersion, phase, impedance, etc.. characteristics to blend together. On top of that, you've just made your three way a four way. More cost and far more complex. As such, it is a step forward or backwards?
As far as larger drivers covering the range above 1.5 KHz, there are a LOT of variables here. The size of the voice coil, the contour and slope of the cone used, the type, size and shape of the dust cap, the type and size of the surround, the design of the motor structure ( magnet & pole piece ), etc... All of these things will alter frequency response, dispersion characteristics, transient response, etc...
While not the "perfect" driver, take a look at this Eminence Beta 12LT. The bandwidth that they get out of this driver is VERY impressive for its' size to say the least. I'm using these as midranges in PA cabinets as they easily cover that entire pass-band with admirable results. The cost is phenomenally reasonable for what you get too. Maybe not "hi-fi" quality, but it just goes to show what proper engineering can do. Sean
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My personal thoughts are that 100 Hz is too low for a driver expected to cover the entire upper midrange region. I also agree with Trelja's comments that optimal woofer crossovers are quite low. What to do?
Well, if you use a "filler" driver aka a "upper bass /lower midrange" driver to fill in the gap, you've now got more dispersion, phase, impedance, etc.. characteristics to blend together. On top of that, you've just made your three way a four way. More cost and far more complex. As such, it is a step forward or backwards?
As far as larger drivers covering the range above 1.5 KHz, there are a LOT of variables here. The size of the voice coil, the contour and slope of the cone used, the type, size and shape of the dust cap, the type and size of the surround, the design of the motor structure ( magnet & pole piece ), etc... All of these things will alter frequency response, dispersion characteristics, transient response, etc...
While not the "perfect" driver, take a look at this Eminence Beta 12LT. The bandwidth that they get out of this driver is VERY impressive for its' size to say the least. I'm using these as midranges in PA cabinets as they easily cover that entire pass-band with admirable results. The cost is phenomenally reasonable for what you get too. Maybe not "hi-fi" quality, but it just goes to show what proper engineering can do. Sean
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