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Which tweeter provides the bigger sweet spot, the horn tweeter or an aluminum dome tweeter?

My local high-end theater equipment store just told me on the phone that horn tweeters have a very narrow listening area, while dome tweeters have a much wider sweet spot. In contrast, I found a few internet articles that say just the opposite . . .

I'm forced to have far from ideal room conditions for my theater set-up (stuck in a corner, but rotated about 30 degrees), so I was wondering which tweeter would provide me with the wider sweet spot, enabling me to accompany more guest seating positions?

Thanks for any help anyone can provide.

Bob
 

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Don't believe everything they say ... Do as you did, a research online to find out the differences :yes::yes:

If you can, ask them if you can try them at home (What better way to decide which one are best for you :bigsmile:) ... if they can't loan you a pair, I'm sure they have a 30 day return/exchange policy ... you can buy a pair and excahnge/return if you don't like them :yes::yes:
 

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Yep... I think Andrew gets the bone on this one. Excellent answer, although I have no idea if he's telling the truth, but it sounds really good. :dumbcrazy: Just picking at you Andrew.
 

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Yep... I think Andrew gets the bone on this one. Excellent answer, although I have no idea if he's telling the truth, but it sounds really good. :dumbcrazy: Just picking at you Andrew.
Why I'll teach you to pick at me! :devil: :boxer: :bigsmile:

A few things. First, all tweeters are "horn" tweeters, in the sense that all of them are loaded on a waveguide of some sort. (A flush baffle is just a 180deg waveguide.) Some of them are designed to improve power response (and thus imaging) by providing constant directivity over a given area, with a smooth rolloff of treble energy past that point. (Many coaxes, such as the KEF Uni-Q and Tannoy Dual Concentric, attempt constant directivity by using the cone profile as a CD waveguide.) Others (e.g. the Tractix flare used by Klipsch and others) does not attempt constant directivity.
While technically you are correct every tweeter is a "horn" this is not the common terminology most are familiar with and I was answering with respect to the OPs terminology.

A 180deg waveguide is basically hopeless, and leads to all kinds of problems in the midband power response, because it does not control the dispersion of the tweeter at the bottom of its passband at all.
I am not sure if I understand your thought process here. With proper integration of drivers (the midrange and the tweeter) this is not an issue at all. *Clarification* What I mean by this is: With the proper crossover settings along side a midrange and tweeter with similar on and off axis responses this issue can be overcome. I am fully aware of this issue due to my current testing in which I am doing exactly this. With a mock baffle set up I have encountered no such issues.

So generally, I think it's safe to say that the best imaging - especially the best imaging over a zone in a room, as opposed to a spot. - comes from constant directivity waveguides, with other waveguides being various levels of inferior to a good CD waveguide.
In terms of the loudspeaker itself it is off-axis response that creates imaging and the sense of a sweet spot. Simple physics dictates that for the largest sweet spot greater off-axis dispersion is required and for this to be pleasurable this response need to mimic the axial response.

Of course the room plays a hugely important role in this situation, but again the OP asked about which type of tweeter which is why my emphasis lay on the loudspeaker not the room.

As far as waveguide versus off-axis dispersion they are two different but interrelated things. A waveguide does exactly what the name implies where the horizontal and in this case less importantly vertical response are "guided." While this can limit a tweeter's off-axis dispersion characteristics it does not entirely control the linearity of these responses which is why this distinction is important. Waveguides can control actual dispersion, but the dispersion itself dictates imaging so I guess in a sense both the waveguide and the tweeters resulting dispersion characteristics will be indicative of imaging/sweet spot sensation. If one is looking for a way to quantify this data off-axis response will be the most important data to collect and analyze.
 

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Clear this up for me... I don't want to misunderstand what I'm reading.

Does this make any speaker other than the Klipsch, KEF Uni-Q and Tannoy DC or similar type horn useless?

I guess all these speakers developers for about 95% of the speakers on the market are not so smart... and the hundreds of speaker reviewers giving good marks to all these speakers with flush baffle speakers just don't realize all the problems that exist in these speakers and really shouldn't be writing reviews?

I wonder how all these speakers companies with flush baffles stay in business with all the problems that exist in this design?

I wonder where my Martin Logan's fit into all this?

And that monkey is just too funny!
 

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Does this make any speaker other than the Klipsch, KEF Uni-Q and Tannoy DC or similar type horn useless?
Not at all. As I am sure you know no loudspeaker is perfect. This is why subjectivity comes to play so greatly when one goes out speaker shopping and listening you are narrowing down choices you are actually removing imperfections that you are more sensitive too.

Also, in some rooms it is preferable to have poor off-axis response. While in a technical sense this is not ideal there are certain situations such as an extremely reverberant room where off axis response would likely need to be tamed for maximum sound quality.

I guess all these speakers developers for about 95% of the speakers on the market are not so smart... and the hundreds of speaker reviewers giving good marks to all these speakers with flush baffle speakers just don't realize all the problems that exist in these speakers and really shouldn't be writing reviews.
One extremely important thing to realize with speaker reviews is that the room they are auditioned in plays a paramount role in sound quality. So the reviewer is reviewing the specific loudspeakers interaction with the given room.

I wonder how all these speakers companies with flush baffles stay in business with all the problems that exist in this design?
I don't know where you got this from, but flush baffles are used very often without problem. Internal to the tweeter (and thus in an area we cannot see or sometimes it just isn't noticed) there can be a waveguide which allows for proper dispersion characteristics without need for baffle compensation allowing for a flush mount with no problems.

If DS-21's reference to a 180 degree waveguide is where this came from I believe he was referring to a situation where a non-waveguided tweeter is used in conjunction with a flat baffle which is exactly what I plan on doing and as I have previously said is an extremely good idea if proper methodology is taken :D.

Baffle compensation is only really needed in the case where a non-waveguided tweeter is used and the tweeter in question has extremely linear off-axis response. If the compensation is not taken off-axis response will be ruined due to wave diffraction issues.

I wonder where my Martin Logan's fit into all this.
I am not aware of any credible 3rd party measurements on the Ascent I's. If you know of any I could give you my thoughts on the objective performance of the loudspeaker. If you wish not to jack this thread feel free to PM me or start another thread.
 

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I don't know where you got this from, but flush baffles are used very often without problem. Internal to the tweeter (and thus in an area we cannot see or sometimes it just isn't noticed) there can be a waveguide which allows for proper dispersion characteristics without need for baffle compensation allowing for a flush mount with no problems.

If DS-21's reference to a 180 degree waveguide is where this came from I believe he was referring to a situation where a non-waveguided tweeter is used in conjunction with a flat baffle which is exactly what I plan on doing and as I have previously said is an extremely good idea if proper methodology is taken :D.

Baffle compensation is only really needed in the case where a non-waveguided tweeter is used and the tweeter in question has extremely linear off-axis response. If the compensation is not taken off-axis response will be ruined due to wave diffraction issues.
Yes... I was referring to his comments... (A flush baffle is just a 180deg waveguide.) and A 180deg waveguide is basically hopeless, and leads to all kinds of problems in the midband power response, because it does not control the dispersion of the tweeter at the bottom of its passband at all.


I am not aware of any credible 3rd party measurements on the Ascent I's. If you know of any I could give you my thoughts on the objective performance of the loudspeaker. If you wish not to jack this thread feel free to PM me or start another thread.
I am not aware of any either. I really haven't even studied the ML philosophy for that matter. :huh: I just can't get over how much I like the sound... even if someone discovers they are design flawed. In that case I would say I am glad they erred. :bigsmile:
 

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Yes... I was referring to his comments... (A flush baffle is just a 180deg waveguide.) and A 180deg waveguide is basically hopeless, and leads to all kinds of problems in the midband power response, because it does not control the dispersion of the tweeter at the bottom of its passband at all.
Yeah, I am pretty sure he was referring to a non-waveguided tweeter with a flat baffle. But I have already discussed why I disagree with this idea and why I even plan on using exactly what he said as hopeless in my current speaker design a couple posts back. Proper integration is key. Ambient field effects will change, but these can all be dealt with using proper planning and design.

I am not aware of any either. I really haven't even studied the ML philosophy for that matter. :huh: I just can't get over how much I like the sound... even if someone discovers they are design flawed. In that case I would say I am glad they erred. :bigsmile:
Then enjoy and don't worry about it :T.
 

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Note that when Toole started employing his blind testing methodology at Harman, good designs (waveguide-loaded tweeters, multiway centers) proliferated and bad designs (flush-mounted tweeters, toppled MTM centers) disappeared from all but the cheapest models, with the end result being that Harman has what I consider the deepest and broadest bench of good speakers right now bar none. Why? One obvious conclusion is that good designs implemented well sound better than bad designs implemented well.

So the upper end of JBL, Infinity, Revel are all some of the better designs? Actually all of Revels centers appear to be the toppled MTM design. Seems to be the same with JBL and Infinity. I'm assuming Harman owns more speakers companies I'm not aware of and maybe I'm not looking at the right models. Can you be more specific? Thanks!
 

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I plan to get a pair of bookshelf speakers with a center for our great room, so this thread may help me decide what to get. I had looked at the Klipsch and the JBLs... particularly the RB-51 and L830.




Bob... if this discussion is not helping you and you feel I'm hi-jacking your thread, let me know and we'll move it. I'm hoping that it's helpful to you though... and others as well.
 

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I've never heard a system with a flush-mounted tweeter that had a consistent sound on- and off- axis. All of them seem to get in trouble at the crossover region. Sure, there are some band-aids (e.g. the BBC dip) but to my ears they don't work as well as just doing it right to begin with.
This statement actually surprises me coming from you due to the extreme objectivity you have shown in other threads. Nonetheless subjectivity is important so...

This lack of consistent sound is likely due to the poor integration. Using a digital crossover along with matching axial and off-axis response you can achieve this consistent sound.

Using something like the Infinity 10PR80BZQ-FW02 4" mid range coupled with a tweeter such as the Neo PDR3 this response can be achieved. The Infinities off axis response at 60 degrees is nearly identical to the axial response up to 3000kHz. The PDR3 has an extremely linear response from around 2kHz to 20kHz with its off-axis response 60 degrees at 15kHz being only -5dB if flush mounted with proper baffle compensation. A combination such as this will allow for complete continuity with proper crossover use as the axial responses are nearly identical.

The real issue with such mounting is the typical DIYer and speaker manufacturer do not invest the time in testing/designing drivers until they are ideal for a given application which is why inconsistency occurs. I will say it can be much harder to achieve proper response using a flush mounted non-waveguide tweeter, but once implemented properly the results are far superior in both an objective and subjective* sense as off-axis dispersion is allowed to flourish in a way not conducive to the waveguided design.

*Both Ian Paisely of Mirage and Floyd Toole of Harman through various double blind tests of thousands of participants found wide off-axis dispersion with similar magnitude to on-axis is preferable.

One thing that I have noticed about these typical horn loaded designs is that their off-axis tweeter response is lacking in said linearity which has been shown to be preferable by the credible perceptual research. This is why I recommend them for highly reverberant rooms as the imaging would be better in such a case or for a near field application, but when compared with a loudspeaker that has a wider, more linear, dispersion pattern (all else being equal) in a acoustically treated environment subjective reviews will fall with the latter discussed loudspeaker.

As far as the discussion that there are only a handful brands putting out speakers worth buying that is simply ludicrous.For example B&W and Ascend Acoustics both quite a few speakers that perform well in the objective sense as laid out by perceptual research as well as the subjective sense. Furthermore, another Harman subsidiary that was never mentioned, Infinity has developed some speakers that are simply superb especially considering their price point. One such example is the Primus 360 (do not confuse this with the Primus 362). The perceptual research conducted does show issues with some designs, but more importantly, if fully understood, gives on an objective method of rating loudspeakers via measurements in the end design methodology should be ignored as it is not necessarily indicative of quality.

For those interested this link has all of Harman's child companies.

I plan to get a pair of bookshelf speakers with a center for our great room, so this thread may help me decide what to get. I had looked at the Klipsch and the JBLs... particularly the RB-51 and L830.




Bob... if this discussion is not helping you and you feel I'm hi-jacking your thread, let me know and we'll move it. I'm hoping that it's helpful to you though... and others as well.
Sonnie, if you tell me your budget for the two speakers I will make a suggestion as the best speaker in the price range tonight. There are far more issues in speaker design than just tweeter directivity that have been shown to increase or decrease listener ratings.
 

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I'll start a new thread for those bookshelves and toss my budget in there.

I did mention Infinity as a Harman company though. I installed some 360's in a home theater system for my wife's boss and we were all impressed.
 

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What changes were made between the 360 and 362?
A reliable source told me that the the new **2 series is an attempt to reduce driver production costs, at the expense of some quality. Based on the measurements at stereophile.com of a 162 vs. a 160 I had on hand, this certainly appears to be the case.

However, I personally do not think the slight quality reduction matters greatly based on the use of these speakers in stock form. The cabinets are resonant structurally, and do not even use sufficient acoustic absorption materials internally. However, some of those Primus **0 raw drivers measure fantastically - essentially good enough to use in unlimited class sound quality speaker systems. The mid-range used on the 360 is a case in point - I bought a replacement driver from Harman and analyzed this unit. The characteristic response properties are unbelievable considering the speaker system in which it was used. But as you know, you can put the best drivers in the world in a shoddy cabinet system with a less than ideal crossover and ruin any potential said drivers may have.

-Chris
 

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The Neo3 is basically at 180deg at 3kHz, and there's no way a 4" midrange can match that.
For one, the mid Andrew mentions as 4", actually has a 3" effective radiating area. Second, as soon as you put a Neo3PDR on a flat baffle, it can have no more effective than a +/- 90 degree radiation pattern, due to the physical size of the baffle in relation to the wavelengths. It is trivial to match these two drivers to have near identical response out to a * +/- 60-70 degree horizontal axis when integrated around 2.5khz. Which is frankly, perfect in practical terms, for perceptual purposes. This accounts for the window of the 1st reflection angle vector typical in most situations, so a near mirror reflection occurs as opposed to one with substantial deviations relative to the on axis response.

That's assuming one can stand that awful little tweeter. Forget the smooth FR, because it has lots of distortion and highly constricted dynamics. I've tried three variants of it, and I've learned my lesson every time. :)
What distortion would that be? I have measured this tweeter, and it has a notably low measured distortion. Certainly nothing near suspected audibility. Distortion measurements on that Zaph site also evidence it to have very low distortion.

-Chris

* In this thread, I intend to mean non-wave guide tweeters installed on baffles with very large radius edges, in the 3" or larger range, in order to maintain linearity on and off axis, thus minimizing diffracting characteristics of the baffle.
 

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No, the real problem is one of physics: a big piston will in general have more limited directivity at high frequencies than a small piston, unless the directivity of the small piston at the bottom of its passband is controlled.
Very true. Hence the need for proper driver integration. If the drivers are not properly integrated they won't sound good together. I have repeated this throughout the thread and stand by it. The area of driver integration is where it seems not enough research is done. Various measurements must be taken of each driver individually as well as in conjunction to see how they interact as the loudspeaker is a system and the sum of its parts.

That is exactly what I'm talking about. The subjective aspect is where it's more important. For my tastes, I'm willing to put up with some top-octave irregularities to get the mid-tweeter transition region really right. Others may have opposite preferences.
I think you have missed my point - If proper time and care is taken neither of these situations need be an issue. Through the previously stated process of proper driver choice, baffle design and crossover implementation one can address both issues in a way to remove them from the system.

For one, the mid Andrew mentions as 4", actually has a 3" effective radiating area. Second, as soon as you put a Neo3PDR on a flat baffle, it can have no more effective than a +/- 90 degree radiation pattern, due to the physical size of the baffle in relation to the wavelengths. It is trivial to match these two drivers to have near identical response out to a * +/- 60-70 degree horizontal axis when integrated around 2.5khz. Which is frankly, perfect in practical terms, for perceptual purposes. This accounts for the window of the 1st reflection angle vector typical in most situations, so a near mirror reflection occurs as opposed to one with substantial deviations relative to the on axis response.



What distortion would that be? I have measured this tweeter, and it has a notably low measured distortion. Certainly nothing near suspected audibility. Distortion measurements on that Zaph site also evidence it to have very low distortion.

-Chris

* In this thread, I intend to mean non-wave guide tweeters installed on baffles with very large radius edges, in the 3" or larger range, in order to maintain linearity on and off axis, thus minimizing diffracting characteristics of the baffle.

Couldn't have said it better myself.
 

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It really all boils down to what sound you like the best.
While that is a noble thought there is a tremendous amount of research in the field that shows there are certain characteristics of tweeters that are desirable while there are others that are not. Numerous blind tests were conducted with thousands of subjects in search of this data.

Look up Ian Paisley on the AES website for example of such research.
 

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My point is, proper driver integration, absent some sort of directivity control of the bottom of the tweeter's passband, is impossible with most standard driver configurations, e.g. the 7" 2-way or MTM.
Whom is suggesting such an illogical combo as a 7" 'midrange' coupled to a standard direct radiation tweeter? Not Andrew. Not Chris(me).

And frankly, the more separate drivers in a system, the more cost required in crossover (be it digital/active or passive) and the smaller the listening window will often become. That suggests a 2-way configuration with a reasonably-sized midbass (10" or bigger, say, or twin 7's or 8's) and a coaxial or waveguide-loaded tweeter as the optimum configuration for home use, IMO.
Such an execution would ultimately mean poor off axis dispersion(undesirable from the perspective of general rules outlined by loudspekaer perceptual research) if you use for example, an 8" for most midrange duty, in a band over about 1000Hz. Generally, such a large mid-range would also have have poor cone behaviour so far as internal break up modes, if used over 1000Hz, resulting in a poor waterfall response. The unit may still have a relatively flat on-axis response, but have various other technical issues when used in such a high band.

Multiple drivers(in a 3 way system as an example) work sufficiently when properly integrated. I do not see the issue so far as relevant performance is concerned in a properly integrated system. A 2 way system is very difficult to pull off while having desirable measured characteristics are dictated as desirable by perceptual research.

-Chris
 
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