Speaker "Toe in" and linearity. How important is it to aim speakers at your ear?

[bigpapa]

I've heard many recommendations to 'toe in' speakers, or only use in walls with aimable tweeters.

I've even heard of toeing in just behind your head...? Why not aim it directly at you?

It makes sense to have a driver moving towards you, at least close to plane of where you are. But then again, don't most manufacturers try to get their speakers to perform well off-axis?

Is it that important or noticeable to have a speaker aimed directly at you? I don't recall ever noticing a difference when using standing or bookshelf speakers. I'll be sure to try and test next time I install some.

When looking at wave propagation recently of the Indonesian Tsunami, the main waves generated out toward the Indian ocean were quite clear. It seemed that there was a line of energy roughly 30 degrees (very roughly) wide where the energy seemed consistent, then outside of that the energy seemed to start dropping off noticeably. Is this a good model to use?

 

[Sheep]

Treble rolls off sharply off axis, so aiming them close to your ears, and have them at ear level is ideal for getting the best treble response.

toeing in also affects the soundstage and imaging and whatnot of the speaker. It takes some playing around with to get right.

SheepStar

 

[ozdvduser]

Best way to aim them is with a laser point, here's a couple of ideas:

[1] put it on top in the middle of the speaker, aim the speakers so that the laser line goes around 2-3inches away from your ear
[2] put a piece of cardboard onto a broomstick handle, get someone to hold the broomstick around 1 1/2-2 feet behind your seating position, aim the speakers so that the laser line meets on the cardboard in the same place from each speaker

 

[bigpapa]

Treble rolls off sharply off axis, so aiming them close to your ears, and have them at ear level is ideal for getting the best treble response.

I understand that Sheep. But, how sharply does it roll off, and is it consistent with all tweeters, or dependent on design? Can a manufacturer improve this or make a speaker perform better off axis?

I understand how to aim speakers, and the principle of aiming it behind your head. But will it be that noticeable if say, the lasers meet just before your head?

What if the speakers are aimed straight out, yet you are seated in the sweet spot within the linear prime dimension of both speakers?

 

[j_garcia]

I understand that Sheep. But, how sharply does it roll off, and is it consistent with all tweeters, or dependent on design? Can a manufacturer improve this or make a speaker perform better off axis?

It depends on the speaker. Some are better off axis than others.

I understand how to aim speakers, and the principle of aiming it behind your head. But will it be that noticeable if say, the lasers meet just before your head?

You can use a laser pointer all you want, but it isn't going to guarantee you perfect sound because it doesn't account for all the other acoustic factors in your room, since a perfect room pretty much doesn't exist unless you live in a recording studio. I use my EARS to tell when the speakers are positioned correctly, and this can take some time to do. My speakers are not pointed directly at my head, they would be a bit behind.

What if the speakers are aimed straight out, yet you are seated in the sweet spot within the linear prime dimension of both speakers?

This will usually give you a wider soundstage, but may not give you pinpoint accuracy of sounds. Try them in this arrangement, then try turning them in quite a bit and compare.

 

[agarwalro]

While toe-in makes the sweet spot a little bit sweeter, it makes other listening positions a little bit less sweet . Toe-in improves directionality and frequency response at the sweet spot, at the expense of degrading it at other listening positions. Bottom line is, if only one listener is going to enjoy the setup most of the time, toe-in may be used.

But a word of caution, because dispersion is reduced, you might find the sound a little lacking in perceived size of the listening area (sound stage), so you will have to find the optimal angle.

 

[bigpapa]

While toe-in makes the sweet spot a little bit sweeter, it makes other listening positions a little bit less sweet . Toe-in improves directionality and frequency response at the sweet spot, at the expense of degrading it at other listening positions. Bottom line is, if only one listener is going to enjoy the setup most of the time, toe-in may be used.

But a word of caution, because dispersion is reduced, you might find the sound a little lacking in perceived size of the listening area (sound stage), so you will have to find the optimal angle.

Thanks, that's sort of where I was going with this.

The problem is that many speaker manufacturers don't spec off axis numbers, or promote their off-axis design. That's a bummer. I find that pivoting tweeter designs are intended well, but they're seated back inside the speaker; sound waves re-direct off the speaker itself; and the tweeter may have to be further behind a grill, further negating any benefit of toe in.

It would be nice to know how a speaker performs off axis when designing a system, say for a small built in theater, or a dedicated 9 seater, or anything in between.

Anybody know how a Bose performs off-axis

 

[jcPanny]

Off axis response

Research by the NRC and Canada has revealed that listeners consistently prefer speakers with a better off axis response in double blind tests. Some manufacturers, like Axiom Audio, use the off axis response as a design criteria and extensiverly test new speaker designs with double blind tests.

 

[Buckle-meister]

...tweeter designs are intended well, but they're seated back inside the speaker; sound waves re-direct off the speaker itself...

The range of frequencies a tweeter will reproduce act more like 'rays' than waves.

 

[j_garcia]

People tend to be more sensitive to high frequencies though, so annomalies in tweeter and upper midrange is more noticable. As sheep said, when moving off axis, the highs are usually the first thing to drop off noticably due to the fact that the tweeter generally "beams" more. My speakers show very good off axis response, however I still find the sweet spot relatively narrow with them.

 

[AudioSeer]

Alot of it depends on your speaker's design and their proximity to reflective surfaces. In general, toeing in will get you better imaging at the expense of soundstage. The only way to know for sure with your setup is to experiment.

 

[westcott]

I agree with a lot of things pointed out here, as well.

But, remember that a toe in suggestions are generally based on two or three channel audio systems.

With home theaters using 5,6,8, or more speakers and having far more people to accomodate, toe in may not be the best solution for a home theater, or necessary IMO.

And, as stated earlier, some speakers are designed differently than others and provide excellent off axis timbre and accomodate room interactions (or avoid them).

I too recommend that you try setting up your system in as many configruations as you can think of and decide for yourself what sound best to you based on the "guidelines" suggested.

 

[Sheep]

I agree with a lot of things pointed out here, as well.

But, remember that a toe in suggestions are generally based on two or three channel audio systems.

With home theaters using 5,6,8, or more speakers and having far more people to accomodate, toe in may not be the best solution for a home theater, or necessary IMO.

And, as stated earlier, some speakers are designed differently than others and provide excellent off axis timbre and accomodate room interactions (or avoid them).

I too recommend that you try setting up your system in as many configruations as you can think of and decide for yourself what sound best to you based on the "guidelines" suggested.

With your speakers being horn-loaded you won't need to toe in alot, if any.

SheepStar

 

[westcott]

With your speakers being horn-loaded you won't need to toe in alot, if any.

SheepStar

Are you reading between the lines again Sheep?

Or have you been looking at my photos in the gallery?

 

[Sheep]

Are you reading between the lines again Sheep?

Or have you been looking at my photos in the gallery?

Both

SheepStar

 

[Bevan]

While toe-in makes the sweet spot a little bit sweeter, it makes other listening positions a little bit less sweet . Toe-in improves directionality and frequency response at the sweet spot, at the expense of degrading it at other listening positions. Bottom line is, if only one listener is going to enjoy the setup most of the time, toe-in may be used.

this doesnt make intuitive sence to me. if i'm in the sweet spot, with speakers toed in to face me, my girlfriend sitting on my shoulder is about 12" off-axis for both speakers no? and with any less toe-in she would experience a greater difference between each speakers 'degree of off-axixness', if you know what i mean. or am i missing something...

cheers

b

p.s whats the theory behind crossing axis in front of the listner?

 

[claudermilk]

Interesting thread. From what I understood each speaker design has different performance off-axis. My dealer actually had me walk around the listening room to hear the off-axis performance of the Paradigms I ended up buying (it is pretty darn good). Some others I auditioned at the time didn't do too well.

 

[agarwalro]

this doesnt make intuitive sence to me. if i'm in the sweet spot, with speakers toed in to face me, my girlfriend sitting on my shoulder is about 12" off-axis for both speakers no? and with any less toe-in she would experience a greater difference between each speakers 'degree of off-axixness', if you know what i mean. or am i missing something...

Your girlfriend will be more on axis to one speaker than the other. and that will cause the problem in freq. response at that location. The speaker to which she is more on axis will sound louder, by how much depends on the off axis characteristics of the speakers. (see crude diagram)

p.s whats the theory behind crossing axis in front of the listner?

Actually the axes should be crossed behind the listener. This is to ensure some dispersion still occurs and the sound stage does not collapse totally.

 

[bigpapa]

Answers leading to more questions

Thanks guys, you're making a good thread. I've a few details I'm trying to wrap up here.

1. Is placement withing a soundstage determined buy (A) power, or (B) timing, or both?

2. If the cross axis point is before you, wouldn't you still get a defined soundstage? Maybe a little less defined, sure.

3. The Rub; how is off axis performance engineered in a driver? Shape, travel, power... moon dust?

 

[Rip Van Woofer]

Thanks guys, you're making a good thread. I've a few details I'm trying to wrap up here.

1. Is placement withing a soundstage determined buy (A) power, or (B) timing, or both?

2. If the cross axis point is before you, wouldn't you still get a defined soundstage? Maybe a little less defined, sure.

3. The Rub; how is off axis performance engineered in a driver? Shape, travel, power... moon dust?

1) The wording of the question is unclear, but I'll take a stab. The placement (of instruments or voices, as I think you meant) is determined primarily by <i>the recording</i> and only secondarily by your speaker/room configuration. If those aren't already in the recording you ain't gonna hear them. If by power you mean how many watts an amp has or how loud the speaker can play, no. Timing: sure, if your speakers are at significantly different distances from your noggin -- talking feet, not inches. Otherwise no.

2) Never tried it. Can't imagine it being necessary.

3) The driver is only part of it. Hint: that's why tweeters are usually domes. (I can remember when cone tweeters were still common and domes were The New Big Thing!) The baffle/cabinet the driver is mounted on, and even the crossover have a lot more to do with it. Basically, even a well-designed driver will become more directional, i.e., it's frequency response will decrease off-axis, as the wavelength approaches a certain ratio of the driver's diameter (I forget the figure). For example, a woofer or midrange driver that is crossed over at a frequency above that point will exhibit poor off axis behavior which can affect the soundstaging and overall tonal balance even if the speaker has excellent on-axis performance. A lot of otherwise good speakers do this.

And then there's the whole issue of cabinet edge diffraction. Oy. Don't ask...

One thing toe-in does (hinted at in an earlier post) is to direct sound away from the side walls, hence reducing the most common source of early reflections that can mess up soundstaging and the sound in general.

Of course, if your sidewalls are lined with shelves/bookcases or other absorbent or diffusive "stuff" that's not an issue. Or if you're lucky enough to have a really big room with lots of space between the speakers and sides, ditto. Maybe. Every situation is different!

For my speakers and room, the usual aiming them behind the back of my head works best.

FWIW, soundstaging and laser-like locational cues are of secondary importance to me, though certainly nice bonuses. But live music almost invariably has a more "diffuse" sound. I think in a symphonic performance the only people to enjoy that kind of precise soundstaging are the conductor and a few people in the best seats!