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Phase Coherence or Time Alignment: Which More Imp?

This thread is really a follow on from a prior one that I let lapse. Thanks to everyone who contributed and helped me to better understand the importance of crossover design in building a loudspeaker. What I gathered from the last thread that there are opposing camps with different philosophies in crossover design. Leaving aside for a moment those that champion steep slope designs, my question is for those who have experience with speakers that are time aligned and/or phase coherent (using 1st order 6db per octave crossovers). Which is more important, phase coherence or time alignment? In other words, which more strongly influences the sound and performance of a loudspeaker? The reason I ask is because of the four speaker lines currently on my shortlist of floorstanders, three are either phase coherent or time aligned or both. The Wilson Benesch Curve's/ACT's and the Fried Studio 7 use 1st order crossovers but do not time align the drivers through the use of a slanted baffle. The Vandersteen 5's and the Quatro's both time align the drivers and use 1st order crossovers. I guess what I am asking is do you need to do both or is the real benefit in the crossover design? I'd appreciate your views.
BTW the other speaker is the Proac D25 and D38
dodgealum
skrivis
30 posts
 
I regret that I never got subwoofers to match my C/3-Ls. I am planning to buy a pair of Monitor 5s, which likely don't image as well, but have better bass and maybe even better midrange due to less reflections back through the cone.

The Monitor 7s evidently may have bass that's a bit better than that, but they use a tweeter that is not as good.

Perhaps a much deeper C style cabinet would help avoid reflections, but you're still dealing with pretty tight spacing. The larger cabinets of the floor-standers give you much more room for the line and its folds, but you get a larger front baffle along with it. Topping a rectangular cabinet with a truncated pyramid would help, but then your cabinet costs go way up.
skrivis
30 posts
 
Suits_me> Is there a vintage site with a picture of the C/3L?

There is a picture at: http://groups.yahoo.com/group/IM_Fried/?yguid=180415640

They appear to be of early-middle vintage, judging by the drivers. My C/3-Ls resembled these at one point, although I used a single piece of foam to cover the tweeters without a cutout for the dome. (The foam they sell for air-conditioner filters works quite well.)
suits_me
121 posts
 
Thank you all for the interesting info and links.

>You don't need a stepped baffle to get time-alignment. A sloped front baffle actually works better.

I was imprecise, and meant to indicate aligned acoustic centers, be it via stepped or sloped baffles or adjustable drive units.
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