How important is time alignment?

[Boomzilla]

I saw a guy on the Klipsch forums that did this:



So now the question: Does time alignment really matter? Obviously, makers like Thiel believe that not only does time alignment matter but also phase alignment. Other makers (and in this case, specifically Klipsch) feel that time alignment is academic so long as frequency response measures flat.

Your thoughts?

[klinemj]

I think that time alignment is critical...if it's off, the whole soundstage is off.

Mark

[audiohead]

A friend of mine has those same speakers they are awesome.

[garbulky]

They do look great!

[Chuck Elliot]

Jan 5, 2013 16:40:58 GMT -5 garbulky said:

They do look great!

This Klipsch restoration is done by a guy named Greg Roberts, Volti Audio, up here in Maine:


LaScala and Klipshorns

[Chuck Elliot]

A growing number of people have been dealing with time alignment issues that Klipsch and horn speakers in general have by using DSP time alignment and bi/tri-amping.

In other words, after the DSP divides the signal into the crossover bands, each channel "may" be delayed in time.

The first speaker I ever heard that was time aligned was the DQ-10. I think it makes a huge difference.

[hemster]

Time alignment certainly matters. Believe me, it has an audible effect.

[Boomzilla]

OK, then, I can do that.

[AudioHTIT]

Jan 5, 2013 21:59:42 GMT -5 Boomzilla said:

OK, then, I can do that.

I'd want to do a non-destructive test first, I think they took a nice looking speaker and made it look like ... less good.

However I agree with the others, time aligned speakers seem to give the best image and transients - planers are naturally time assigned. Though (channelling PCGuy) I've read some studies that say you can't hear the difference.

[stiehl11]

Ok, stupid question; what is time alignment? And, for those that don't know me, I'm going to compare it to real life performances so, if it's what I think it is, you'll have to convince me of a real world case.

[AudioHTIT]

Jan 5, 2013 22:25:14 GMT -5 stiehl11 said:

Ok, stupid question; what is time alignment? And, for those that don't know me, I'm going to compare it to real life performances so, if it's what I think it is, you'll have to convince me of a real world case.

Time alignment in speakers is when the wavefront from all the drivers reaches your ear at the same time, or more correctly in the same relationship they had to each other on the original recording. One way it's done is by aligning the voice coils of the individual drivers in the same plane, so that a sound leaving all of the drivers reaches your ear at the same time. As is somewhat intuitive, a planar speaker - like a Magnaplanar or most electrostats - is naturally time aligned because all frequencies emanate from the same plane.

[wingrider07]

I would say time alignment is one of the best things about my Acoustats. To my ears, time alignment is analogous to putting on glasses for my eyes. Nothing is added to what I see or hear everything is just more sharply focused. Because electrostats use a single element to recreate the entire musical spectrum, the music is always crisp and clear, never smeared or blurry. Attack and decay is always precise. I've never experienced this level of focus and extreme detail in a conventional loudspeaker. I'm not saying it doesn't exist, I'm saying I've never heard it.

[audiohead]

AudioHTIT..Spot on! Its is also why that Klipsch speaker box is built like that to help move the "Waves" if I may use that word term.The first time I had the pleasure of hearing a pair was back in the 80's I was blown away by how Real to music sounded from them.The guy had them in his bedroom side by side driving them with a Carver amp and using a Tube pre-amp and Realistic Tape Deck!

[audiohead]

As much as I like my Lsi-15's and Matthew Polk design the cabinet of that speaker with that in mine,but still the LSi's are No match too the Klipsch cabinet design.Lets face it you can only get so much out of a slim tower design.Chuck Elliot thanks for posting that photo, Beautiful speakers! I would love too hear them bad boys.

[DYohn]

Time-alignment IS phase...

[klinemj]

+1...had meant to comment on that in my post but forgot.

[stiehl11]

Jan 6, 2013 2:06:48 GMT -5 AudioHTIT said:

Jan 5, 2013 22:25:14 GMT -5 stiehl11 said:

Ok, stupid question; what is time alignment? And, for those that don't know me, I'm going to compare it to real life performances so, if it's what I think it is, you'll have to convince me of a real world case.

Time alignment in speakers is when the wavefront from all the drivers reaches your ear at the same time, or more correctly in the same relationship they had to each other on the original recording. One way it's done is by aligning the voice coils of the individual drivers in the same plane, so that a sound leaving all of the drivers reaches your ear at the same. As is somewhat intuitive, a planar speaker - like a Magnaplanar or most electrostats - is naturally time aligned because all frequencies emanate from the same plane.

Fist a disclaimer: one of the claims from the company that makes my speakers, Phase Technologies, makes is that its flat piston drivers makes sure that all sounds emanating from the speaker do so at the same time.

I think this is popycock. Why? Well, because of this:



This is just one example of real world acoustics that blows time alignment out of the water. For those of you that are unsure of what you're looking at, this is a symphony orchestra. Sound emanates from each of those instruments much like a speaker. As you can see each one of those instruments are at different locations; front to back, side to side. There is no time alignment on those instruments. I've sat at this hall as both a performer and a listener and can tell you that there isn't a "sweet spot" or a bad seat in this particular house (and several others that I have performed at or attended).

Now, I know what you're thinking, "I don't listen to classical music". Well, I don't listen to exclusively classical, either. In fact I've seen two "rock" concerts this year as well. I can tell you that those speakers, playing at over 100 db at my listening location, were not all on one plane and not time aligned. The sound was top-notch, enjoyable, and not fatiguing.

What both of these examples show is that you can have your speakers or instruments 1 foot or 30 feet behind one another and should not be able to notice a "time shift" in the sound. What you should be able to tell, if your speaker is more than a foot off axis, is that it is off axis. This is due to our aural ability to determine depth. A correction in volume in the far speaker to match the volume of the near speaker is all that is needed (and which is why you don't notice depth when listening to a live performance at the symphony; they're placed in that order on the stage for a reason ).

DYohn hits it on the head in that phase is important; to a degree. At Emofest, on the afternoon of the last day (not long before they would shoo us out because they were going home) someone in the 2-channel listening room noticed that the sound wasn't what it should be coming from the speakers. At some point in time, after the last TacT demonstration, someone had reversed the polarity (phase) of one of the speakers. There was a noticeable improvement to the sound, but only because one of the two speakers was 180 degrees out of phase. And, considering how many people were in that room enjoying the "great sound" while I was in there for over an hour, not many people noticed it. For the record, I noticed it but did not think it was out of phase, just that the speakers did not sound all that good.

[klinemj]

Dave...the point on speaker time alignment in that if the speaker does not accurately send what was recorded, it won't sound like the spatial arrangement should...in other words, the violins won't be in the right place relative to each other and the cellos and...

In live music, it is the time at which the notes reach our ears which give us our sense of location of the sounds relative to each other. Same needs to be true when presenting recorded music.

Re the 2 channel room...I thought the speakers there didn't should very good either. It is not surprising that a cable was electrically out of phase.

Mark

[Boomzilla]

OK - My LaScalas look funky anyway. I've got them covered with peel-and-stick vinyl flooring to make them at least slightly living-room-ready. It won't matter to me if mine get sliced, diced, and peeled.

If there's audio benefit to dropping the tweeters back to the plane of the midrange drivers, then it's easy to do. If I don't like it, I can just put the things back where they started with four screws per tweeter.

I'll let y'all know how it sounds.

Thanks - Boomzilla

[Deleted]

Our ears are remarkable for spatial location; we hear two chirps from a bird and we can instantly locate it in the tree. We don't aurally locate because the sound is louder in one ear than the other, that would be too crude. Our brain analyzes the phase shift between our two ears, of the bird's chirp. Our head contains and amazing phase analyzer.

But we don't live in a mono-phase world. Even sound coming from a single speaker soon bounces off walls producing delays and phase shift; which we interpret as warmth and room ambiance. The dramatic improvment in musical realism with the change from mono to stereo wasn't just because there were two sound sources (left & right channel). It was because all the constructive and destructive interferences of the phase shifts between the two signals brought the sound alive. That's why we are going to 5.1 and 7.1 in our music; more realism.

Electronic organ builders quickly learned that the cheapest and quickest way to a more realistic sound was to add more channels.

In the real world, music is a mad jumble of frequencies and phases coming from different instruments, with different near and far field reflections, with different phase shifts for frequencies, and every time you turn your head. The brain understands and enjoys this cacophony of sound; its what makes music sound non-artificial.

It's possible that in an Anechoic Chamber an instrument can measure a difference if your tweeter is 2" forward of your woofer; but in the complex real world your ears don't give a sh*t. But if it matters to you, try a single mono speaker in an anechoic chamber and see if it surpasses your music expectation.

Sincerely
/blair