Designing a 4th order 3 way passive crossover

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Power ratings on tweeters normally specify with crossover point at X Khz and 12db per octave or higher. My guess would be it is only rated at 100W with 1200Hz 12db electrical crossover. The datasheet does not have these details which is a little unusual.

Tony.
 
Tweeter power dissipation is assumed to be program power handling,
so only a percentage of this can tweeter withstand. How do you
suppose the thinner enamelled wires of the tweeter could ever
survive more heat dissipation than the woofer?
 
Dome tweeters are delicate devices and their structure can not
take enourmous power without getting damaged. Many have thought
the same and unfortunately suffered a device failure. What manufacturer
says about power capabilities is not particularly useful. You gotta have
experience to understand this.

No specification can outsmart the common sense.
 
Hi,

Simply put it will run out of excursion x/o at 500Hz.
Distortion before overload will be mediocre. About
1.5KHz LR4 acoustic is the sensible limit of the tweeter.
Acoustically it rolls off about 1KHz, so 500Hz is not realistic.

Power handling is nothing like 100W rms, thats 100W rms
pink noise via some sort of standard high pass filter.

See Zaph|Audio - ZDT3.5 for full SPL modelling
of a 2" dome x/o 2nd order LR acoustic at 400Hz.

rgds, sreten.
 
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Theres the first 2 with my very own box design, much more ridged than a standard box, easy to assemble and no need to wait for the glue to dry.

speakers.jpg
 
They look strong. That takes care of the bass and panel resonance. The woofer could cause the box to ring if you mount it solidly, you could try a gasket and rubber washers under the bolt heads.

You can test the baffle size and shape by bunching a woolen pillow case over the top near the front, and listening for a difference.
 
They look strong. That takes care of the bass and panel resonance.
Beyond a basic level of required stiffness speaker panels primarily require damping not further stiffness to reduce the level of radiated cabinet sound. For example, doubling the thickness of the panels will indeed reduce the level of sound radiated away from the resonant frequencies but at the resonant frequencies the force due to stiffness is cancelled by the inertia leaving only the forces due to damping to determine the level of the peak. A stiffer cabinet will have raised the frequencies of the resonances but a higher frequency resonant motion requires a smaller deflection to be as equally loud as a lower frequency panel resonance (e.g. woofers vs tweeters deflections). To make matters worse, depending on the frequency range, raising the frequency of the panel resonance will make them easier to perceive below the output from the driver.

Somewhat counter-intuitively the net effect of making cabinets with thicker walls may well be to make the cabinet radiation more intrusive.

The woofer could cause the box to ring if you mount it solidly, you could try a gasket and rubber washers under the bolt heads.
Isolating drivers in this manner will indeed reduce the forces going into the cabinet and radiating sound from the cabinet but it will reduce the size of the mass reacting to the motion of the cone. It will also provide a mechanism for the motion of the driver to continue after the signal has stopped dictating a resonant frequency well below the passband of the driver. For woofers you are likely to find the sums do not favour rubber grommets but this is less likely to be the case for the smaller drivers.
 
I agree.

On the other hand damping material reduces pressure on the panels coupled via the enclosed air with rising frequency.

The soft coupling needn't be compliant enough to decouple the bass and would probably benefit from damping itself. My guess is it's worth a try.
 
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