First Order Crossovers: Pros and Cons


I wonder if some folks might share their expertise on the question of crossover design. I'm coming around to the view that this is perhaps the most significant element of speaker design yet I really know very little about it and don't really understand the basic principles. Several of the speakers I have heard in my quest for full range floorstanders are "first order" designs. I have really enjoyed their sound but do not know if this is attributable primarily to the crossover design or to a combination of other factors as well. In addition, I have heard that, for example, because of the use of this crossover configuration on the Vandersteen 5 one has to sit at least 10 feet away from the speakers in order for the drivers to properly mesh. Is this really true and if so why? Another brand also in contention is the Fried Studio 7 which also uses a first order design. Same issue? Could someone share in laymans terms the basic principles of crossover design and indicate the advantages and disadvantages of each. Also, what designers are making intelligent choices in trying to work around the problems associated with crossover design? Thanks for your input.
dodgealum
An even more telling part of the article regarding the group delay of a 8th order L-R crossover.
"Is It Audible?

The conservative answer says it is not audible to the overwhelming majority of audio professionals. Under laboratory conditions, some people hear a difference on non-musical tones (clicks and square waves).

The practical answer says it is not audible to anyone for real sound systems reproducing real audio signals."
It always amuses me when someone makes the claim "It's not audible. Well, not audible to most people most of the time, anyway. Or at least not audible to some people some of the time....."

This is fundamentally no different than the claims that "all amplifiers sound the same" or "lamp cord is perfectly good for speaker wire." Anyone with good ears can only shake his head at such statements. Maybe they hold true in the world of budget-fi, because at some point those differences get swamped by the colorations of the rest of the system. But in a good system, with good music, the differences are plain as day, and time/phase coherence is no exception.

Now, it is not much of a surprise that Rane (and others) would downplay the audibility of time-and-phase coherence, given that they are in the business of selling high-slope crossovers. And in the pro audio world, this is indeed likely the best overall compromise, given that power bandwidth is a serious consideration. I mean that with total sincerity-- if I were designing a pro system with active crossovers, 4th or 8th order L-R would be my first choice, no question. But that doesn't necessarily make it the best for ultra-high-end home audio playback, where other priorities (fidelity to the musical signal in both time and amplitude, for example) take on much higher importance.

The most telling truth is that once someone has lived with a really good time/phase coherent system for some time, he finds it impossible to ever "go back". The lack of coherence in high-order systems, while potentially ignorable if one has never tried anything else, is nonetheless a major step backwards once one has heard the possibilities of an electrostat or a good first-order design. And since the vast majority of systems on the market are still non-coherent, it is quite possible that the majority of audiophiles have never actually lived long-term with a time/phase coherent system, and simply don't know what they're missing.

Luckily, forums such as these allow the minority not only to make our voices heard, but more importantly, to plant seeds of inquiry in the minds of those who may have simply never thought about such subjects before. For to me, there's nothing more satisfying than seeing that light bulb go off, and hearing someone say, "Wow, it sounds like real music!"

Best,
Karl
Is it audible ? I think the best answer is for everyone to demo for themselves and answer for themselves.
I was only quoting from the same source that was cited, since the earlier quote gave an impression that was different than the articles author intended.

Musical realism is the goal of every high end audio designer.

While visiting our local library last week, I heard some symphonic music and immediately thought "that sounds right!"
So I went to see what could sound like an orchestra in a library, and found....a live orchestra practicing in a library!

Each and every design approach has its advantages and its trade-offs. Getting a realistic sound from a system is a complex topic, and a sucessful design is the result of many decisions. The crossover slope is not the sole determining factor in the sound of the speakers. Examining the crossover slope in isolation is impossible outside the digital realm -
you are always introducing variables as the drivers interact and new radiation patterns are established.

I sympathize with the minority given voice on the forums. After all, I am the only manufacturer with Infinite Slope crossovers! I think its important to look at the acoustical wave interference and lobing patterns of the speaker - but since most other companies have no solution to these problems it is seldom talked about except on these forums.

Jeff