Does Time alignment and Phase coherency make for a better loudspeaker?


Some designers strive for phase and time coherency.  Will it improve sound quality?

jeffvegas

@rooze  I wonder if the Evolution Acoustics MM3s which have a family resemblence to Dunlavy Vs have similar time alignment.  Does anyone know?

 

Despite the truly great sound emanating from Dunlavy's, I cannot tolerate single point/seat listening.  Sure, it's great for me, but not for my wife and my friends who sit across a 10 foot couch.   I am looking at speakers more like Von Schweikert's which have a very broad listening/seating area for tonal equality many feet in width.  My wife hated the Monolith IIIs in 1997 prior to my getting Legacy Focuses and double pair of Hallographs.  

I just think it's amazing I've started a discussion without saying anything is the KING. 

@holmz , you can be snarky all you want as long as you are right. If I posed as a Buddhist everyone would die laughing.

Although timing errors can affect imaging frequency response variance between channels causes much more damage and that is easy to demonstrate.

As long as DSP has control over individual drivers it can perfectly adjust timing in one listening location. Most multiway speakers do not allow for this. They have to be bi or tri amped. However, time alignment is most important for subwoofers as diminished transient response affects impact. Fortunately, subs are amplified separately. DSP was extremely effective 25 years ago with the advent of Radomir Bozevic's TacT Audio. He wrote the book on "room Control." With the faster processors we have today it is even better due to increased bit depth. My solution to the problem since 1979 was to use one way loudspeakers with subwoofers. There was no easy way to time align subs until the mid 90s with TacT's processors. Today the best are probably Trinnov's units. But inexpensive and effective ones are available from MiniDSP and DEQX. Used correctly they can improve almost any systems performance even the ones owned by digitally phobic people. It is all just lay instinct. 

Rooms certainly are "Time" sensitive. Reflections occur in time and their timing determines how we will hear them. Unless you like listening to bands in a closet early reflections are always bad. People say that late reflections are in part a benefit and one should not get rid of all of them or the room will sound "dead." I am not so sure about that. Timed reflections are in the recording giving you a sense of the size of the venue the recording was made in. Studio recordings frequently have fake late reflections added (reverb). The problem for home reproduction is that these sounds do not come from the right direction. I am beginning to think that in most home situations there are no late reflections only strong vs weak early reflections. If the room is big enough you get echo which is peculiar to that room and only pollutes the music with sounds that are not supposed to be there. 

As I said earlier in this thread, I have compared 2 speakers, one set time aligned, the other set, not.

They are Jeff Bagby's DIY kits, the "Kairos" speakers, and his "Adelphos". Same drivers (the great SB Acoustics 'Sartori' ring radiator tweeter and 6' MID), same size enclosures. The Kairos are aligned, the Adelphos were designed for those who don't want to tackle building an angled enclosure. 

As good as the Adelphos are, the Kairos created a bigger soundstage and more precise image.