Has anyone heard the Vandersteen 7 or 5a's? I've been lusting to hear these for quite some time. How do they compare to other speakers.
Utilizing a 1st order XO they are Phase + Time accurate (as much as you can get from passive), How important is it to you and why?
If you have to suffer with the terrible 6db rolloff of the 1st order, is it worth the phase accuracy? Or would it be a better decision to just go 2nd to 4th order and not worry about it.
I’ve heard Vandersteen 2s and 3s (but not the 5 or 7) and they are excellent speakers. The model 3 costs much less than the 5, and except for the built-in powered subwoofers, they are similar designs.
Among many other features, they do have 1st order acoustic crossovers. When I say “1st order acoustic”, I mean the roll-off slopes of the sound from the drivers, as they get signals from the electrical crossover, measures at 6 dB per octave. These crossovers are very complex – they have many more parts than a simple 1st order electrical crossover. They are difficult to design and expensive to build.
A problem with Vandersteens, probably caused by the 1st order crossovers, is that there is a very narrow sweet spot where the sounds are time and phase correct. If you move your head slightly, you loose any advantages it may provide.
This question has often been debated, and to my knowledge a clear answer has never been provided, probably because there is no simple answer. I think what is important is that in the crossover range, where both drivers are operating, it is important that the drivers’ frequency response be very smooth and relatively in phase with each other. For a 1st order crossover, that may extend more than 2 octaves above and below the crossover point. There are few drivers available that can do that. For a 2nd order crossover, that range is probably about ±2 octaves, and for a 4th order crossover it is about ±1 octave. I have heard others propose the idea that Vandersteens sound good because they have very rigid cabinets with front baffles built as small as possible. That also makes sense, but as far as I know, it has never been demonstrated to be responsible for their good sound.
Let’s clarify one point. 1st order crossovers keep the drivers in phase with each other, i.e. “phase accurate”, but the slanted front baffle is what makes drivers time accurate. Because woofers are deeper physical structures than tweeters, their “origin of sound” is further away from the listener than that of a smaller driver like a tweeter. To correct for that, a tweeter is placed further back, or the baffle is leaned back.
Linkwitz-Riley 4th order crossovers are also phase coherent, if not precisely phase accurate. The drivers are 360° out of phase with each other. That is no different than in phase, only they are 1 full cycle out of time relative to each other. To my knowledge, no one can clearly hear that difference.