Can you hear the crossover point of a speaker with a well-designed crossover?

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You can hear the transition between drivers if one is superior to the other. For example, I once heard a system with a dynamic woofer and a plasma driver for the rest of the spectrum and you could easily hear where the plasma driver was taking over.

Where drivers are of equal quality my answer to your question would be no. But, as these things often go, someone will claim that they can listen to a speaker system blindfolded and tell what the crossover frequencies are.

This is a good question and I look forward to hearing the various replies it is sure to generate.
 
Sometimes...

IMHO it is hard to place the cause of a noted effect when listening to a speaker, but easy to know if things just sound right or not. I have heard undersireable effects that I believe where the result of the crossover, but made even more audible by the fact that the two transducers being crossed where of different materials/types and located at extremes on the baffle, i.e. - electrostatic panel on top and cone woofer driver on the very bottom. I have probably listed to over 100 very high quality stereo systems (not claiming to be an expert, just stating that my sample base is fairly significant) and my most memorable experience was a top of the line Linn active system at a dealership in Texas back in 1998.

A few years earlier I had heard a more entry level system from Linn that was fully active and was able to compare directly the same day in the same room with the same major components in a passive crossover system (as Linn offered the active boards as plug-ins for the amps as an upgrade path for this particular system). Both were excellent, but the active system again was far more dynamic and coherent sounding to me. Though I have always believed that both the resources and effort Linn is able to put into their active designs are so substantial that one may be foolish to expect their personal projects to yeild anywhere near the same benefits... but hey, giving it a try is why we are all here at this forum !!!

As I type this I am listening to Audio Physic Tempo II's driven by Perreaux electronics, and I have always thought that Audio Physic speakers were among the most coherent sounding in the business compared to other mutli-driver companies out there. I do not feel like I can hear where they cross between mid-woofer and tweeter, but I feel that I can hear, or maybe more appropriately just sense that though very pleasing, there is something somewhat less than completely natural going on between the source and my ears. Maybe just the fact that I am interested in single driver systems has increased my psychosis, but then again maybe I am honest with myself about what I am hearing, who knows for sure, I sure as hell don't.

I think the real answer to your question is, yes, to varrying degrees that are often directly correlated to the expertise of the systems designer and driver choices. I believe that any crossover point below 300 Hz is best done with an active system and with a little care will yeild superior results. Beyond that I think it is entirely possible that given current technical standards and practices it is so context dependent that it is really impossible to answer with any credible authority.

My two cents plus a nickel or two....
 
The placement of images in the soundstage is an area where the nearly unavoidable phase differences between drivers shows up. You are listening to a very believable presentation, and some notes of the piano, for instance, sound like they are coming from somewhere else than you would expect. The summed response of the drivers may give a flat frequency response, but the human ear uses phase information for nearly spherical placement perception. That has been my experience, anyway. Drivers with broad overlaps and first order crossovers, or single driver / no crossover, or active crossovers...
 
The idea is to make a seemless transition between the drivers that is so coherent that you cant here the croosover from one to the other. It rarely happens. Often its the phase that gives the freq away causing the image to jump in space as the music goes above and below the freq of the crossover. This is heard more easily listening to a stereo pair not a single speaker. It is this transition that can make or break a speaker even if the freq response is dead flat it wont sound right due to bad crossover phasing.
There are people who will actually argue that phase makes no difference it is all freq response, dont believe them.
 
The crossover is only half the story...

Firstly, the drivers need to be of similar technology, so that the radiation pattern can be similar. For instance, it's not easy to integrate a monopole configured driver with a dipole configured driver, because of the different power fall-off rate as the distance from the source is increased. But it's not impossible to achieve good result this way.

Then, the correct crossover point and driver sizes should be chosen, or you'll get a poor off-axis response (1" dome tweeter with 10" woofer is good example of a bad combination), as the radiation pattern of a dynamic driver narrows with increased signal frequency. A driver typically has good dispersion at the lower frequencies, but starts to beem at the upper end. So you need to cross over to the next driver before the off-axis response of the driver in question falls off too much. And the next driver has to have sufficient power handling capacity, or it will result in distortion. (When I say "next", I'm progressing from lower frequency to higher).

Good off-axis response is essential in a reverberant/"live" environment. Now, it is acceptible for the system response to roll off when observed from off-axis, but the transition must be smooth, with minimal dips or peaks.

Look up some nice papers from Harman Kardon on this subject. I don't have the urls, sorry.

Hope this helps...
 
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