Sloped baffle

Lewinski... great post. I was impressed by the various digital analyses and corrections that the software was able to effect. Hopefully, speaker manufacturers will be able to achieve greater time and phase alignment, driver linearity and low distortion by designing better X-overs. It may be that the best solution will be an active crossover that can effect the various functionalities that were the subject of your post.

I realize that Richard Vandersteen does this on his high end speakers to some degree, but it sure would be nice if it would be more plug and play. After all, not everybody is a former NASA rocket scientist or a Steven Jobs/Bill Gates computer genius.

Thanks.

The DIY forums and this one have something in common. Very rarely does anybody listen to any advice or criticism that they don't want to hear.

Lewinski... great post. I was impressed by the various digital analyses and corrections that the software was able to effect. Hopefully, speaker manufacturers will be able to achieve greater time and phase alignment, driver linearity and low distortion by designing better X-overs. It may be that the best solution will be an active crossover that can effect the various functionalities that were the subject of your post.
...
After all, not everybody is a former NASA rocket scientist or a Steven Jobs/Bill Gates computer genius.

Thanks Bifwynne.

Not sure if you were implying I'm a computer genius. But to clarify it just in case: I'm certainly not!!! Not even very savvy, honestly! It looks a lot harder than what it is. I just have a dedicated server with JRiver and the Audiophile Optimizer running in it. The hardware is optimized. Amazing sound. And it was a set it and forget it setup.

Cheers!

what is your definition of "premium drivers"? Cost of the driver? Cost of a commercial speaker using this driver? The marketing hype surrounding that driver that makes you believe it must be the best?
From the little I know, some Scanspeak drivers are very good performance that would qualify for time-coherence.
Accuton drivers need not apply for time-coherence.
I don't know much about Raal.
Be careful how you choose your drivers - don't let cost be the judge - look at their freq bandwidth & where you intend to cross them over.

Bombaywalla,

Very fair point. Honestly, I have not done much research on drivers yet. I was trying to provide examples to show what I meant and used the brands that are usually mentioned in reviews as premium. I did look into their prices, and in a way I was think along the lines of price. What would be premium brands sound-wise?

BTW, I never thought about drivers not being time-coherent. What does that mean? I thought time misalignment was between/among drivers.

I have not even started looking into building a speaker. I am now thinking through / coming to terms with moving away from a nice digital and analog chain (Audiophilleo with PurePower going into a Metrum Octave, going into a Lamm LL2) and into a multichannel DAC driving multiple amps directly and using software for volume control. I'm sure many can relate to having second, third, and forth thoughts on such a move.

The benefit of driver time and phase alignment seems to be significant. The benefit of multiamping I believe is well documented, but the challenge is on the implementation. Digital room correction also makes sense to me.

After taking this plunge next step will be thinking which amps to get to drive my existing speakers. And later I will look into building my DIY speakers. Nevertheless I wanted to chime in here to provide a different approach for achieving time alignment.

BTW, yes, in a way this is similar to the Meridian path. But I do like tubes!!! So my idea is a SS or class D amp for woofers and tubes for midrange and tweeters. And I also have two power subs. But you made me remember about Meridian's approach. I will look into it. I believe they deliver a digital signal to the speaker and then convert it to analog inside the amp. I'll check if they have processors that deliver multiple analog channels, but I'm also wary of spending big on digital components considering it is not yet mature and hence evolving so fast.

As I said before, great thread!

BTW, I never thought about drivers not being time-coherent. What does that mean? I thought time misalignment was between/among drivers.

Let's look at just 2 of the physical components of a driver (imagine a midrange driver): the cone and the suspension (the surround and the spider).

The cone itself has mass, and because of the kinetic energy of a cone moving outward, it sometimes just can't reverse direction as quickly as the signal is asking. Sure it responds, but with a very slight delay. This delay is one source of phase distortion.

The suspension not only centers the coil in the gap, but defines the resting position of the coil within the gap. Don't believe me? Gently push in on a mid-woofer, and let go. The speaker pushes back out to the resting position as defined by the suspension.

Now, small movements around the "resting point" all experience the same (minute) amount of resistance from the suspension. This is by design and is where the driver operates with minimal effective phase distortion.

Now, midrange drivers require larger strokes to produce lower frequencies, and the suspension applies more (nonlinear) resistance against the movement of the driver as the driver approaches X-max, imparting another set of phase distortions.

This is an oversimplification of the subject. But shows that (good) time-and-phase aligned speakers require more than just a sloped baffle and first-order crossovers.