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Join Date: Mar 2003
Location: Lower California
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Remember, this is designed to be an inexpensive, high-power PA speaker that can project sound hundreds of feet out, not just to your couch. The woofer construction for high-power operation is fairly straightforward. The HF section, however, is likely quite delicate -- probably would not handle more than fifteen watts continuous power before failing. It is therefore necessary to place as much of the HF load as possible on the relatively burly woofer, hence the high crossover point. Again, if the woofer is designed with attention to this, it will not necessarily penalize the frequency response (though, as noted, the transient response may not be optimum).
There is a significant dropoff in HF spectral power density with a 3.5 kHz instead of 2 kHz highpass filter. Few if any natural musical instruments produce fundamental tones above 3.5 kHz, so it is mostly harmonics above there. Harmonics are usually highly damped -- even cymbals, with their high initial peak energy, have modest actual power (energy though time). This dynamic is obvious to anyone with an add-on RTA in their rig, going back to the Winamp days.
If the woofer falloff above 3 kHz is steep, there is no need for any series elements as they will noticeably reduce the sensitivity (i.e., loudness) of the unit. Inductor coils are usually the bigger deal with filters; it makes perfect sense to just use one inductor, with two flanking capacitors, to get a three-pole 18 dB/octave filter slope for the delicate tweeter, which will make that increasing lower octave power easier for the tweeter to digest.
Add in some attenuation, polyswitch protection and the tweeter should be able to withstand the rigors of live use. Which, remember, include occasional live microphone feedback where the amplifier is at full clipping long enough to toast a tweeter -- something that couch potato-ing does not involve. A lower-frequency, complementary-filter crossover could be introduced for non-live use which may improve the transient response and widen the directivity. I would expect the "improvement" to be modest, but there will also be a penalty (2-3 dB or so) in the overall sensitivity that is a major feature of this unit for home use. (Stay away from karaoke, though...)