A Question About Time Alignment


I was reading a review of the Wilson Alex V on Stereophile recently. (Published just in time. I’m thinking about picking up a pair. Maybe a couple for the bedroom, too.) And it raised a long-standing question of mine, one that I hope the wiser minds on this site can answer. 
 

Wilson’s big selling point is aligning the different frequencies so they all reach your ear simultaneously. As I understand it, that’s why they have minute adjustments among the various drivers. The woofers put out bass notes that move slowly thanks to their long sound waves while the tweeters are playing faster moving, high frequency notes with short waves. Wilson lets you make adjustments so that they all arrive at the ear at once. 
 

It seems to me, however, that live music isn’t time aligned. Suppose I’m playing the piano and you’re sitting across the room. When I stretch out my left hand to hit the low notes, those notes travel along the same long, slow wavelengths as the notes from Wilson’s woofers. Similarly, the treble notes I play with my right hand move quickly through the short wavelengths. The notes from the piano are naturally out of alignment. If Wilson’s goal is to achieve a lifelike sound, aligning the frequencies doesn’t seem like the way to do it. 
 

Wilson has been selling lots of zillion dollar speakers for lots of years and people continue to gobble ‘em up. Something must be wrong with my line of reasoning. Would someone please point out where I’ve gone wrong? Nicely?

paul6001

Phase really is time, if drivers are out of phase with each other, frequencies are leaving the drivers at different times, thus effecting time alignment.  I hope this all makes sense and helps in some way.  Tim

No you are just confusing the issue even more. Phase and time are two different things. time cohesion implies phase cohesion but not vice versa. So not equivalent at all. Time coherence between two drivers is about aligning the start of the waves coming out of each driver. You can have phase aligned yet time non aligned. 

On speaker design what we align is the portion of each driver where the sound is emitted, which is normally, aligning the front of each voice coil.  This allows all drivers sound to reach the ear at the same time. .... drivers can be staggered or sloped.   

This is also nonsense. 90%  of speakers are not sloped or staggered and nobody is complaining. Time alignement has never been proven to be beneficial let alone audible it is only for marketing. 

I am very disappointed in you Tim. Was waiting for your custom tuned circuits and they never materialized.

~Master Kenjit, speaker tuner and master audiophile.

in colloquial speech fast or slow refers to time. For example fast food refers to food that is prepared quickly. There is no mention of distance in that.

@kenjit but we’re not talking about cables being like a pizza, or how quickly KCF gets a bucket ready.
It started off with time alignment, and then went towards the speed of sound… so it seemed like a technical discussion rather than a colloquial one?

First, if you intend to "pick up" a pair of any Wilson speakers....bring a crane!

Second, while the provability of "time alignment" claims for speakers has been argued since the launch of Dahlquist DQ10s, the fallacy in your reasoning is this...the arrival time cues in a recording are baked into the stereo microphone pickup of the event.  The speaker's job is to restore them to your perception in your room without altering them.  That's High Fidelity 101.  Which is also why assessing playback fidelity with multitrack recordings is a waste of time.  Only "live to 2 track" unamplified, unprocessed recordings, whether classical, jazz, or folk or any subgenre of acoustically produced music is of actual use.  Once accuracy is found acceptible, bring on your favorite commecially recorded selections, knowing you are hearing them as they are.  

Monopulse Loudspeakers here in the UK have made this time alignment issue their main selling point for decades.

The designer Allan Hendry has been stating that impulse precision is hard wired into our evolution for survival itself and thus it’s importance cannot be overstated.

Everytime I’ve listened to Monopulse speakers they did seem to be easy on the ear, very listenable for long durations. That led me to also wonder whether they are onto something.

If so, does that mean most others aren’t?

http://www.monopulse.co.uk/