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Phantom center only better!

TankTop

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Lately I’ve started listening to music at night to help me sleep. My Focal 706’s are toed in slightly and I’m just forward of 90° With listening levels extremely low and loudness on. The stereo imaging is stunning with the feeling of floating in the phantom center, I think Focal’s inverted dome tweeter lends itself to this imaging. Similar to headphones but much more substantial.

Anyway, if anyone has thoughts on this please share.
 

Chromatischism

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Well you do need wide dispersion to the top octaves to maintain a good response off-axis like that and the inverted dome does help to achieve that better than any non-waveguided dome tweeter I've seen measurements for.

I have a similar setup with my S400's and they are almost magical in that sense with the constant directivity but I'm really impressed by what Focal can do with the inverted dome.

With the typical narrowing-dispersion speaker as frequency increases, you need more toe-in to maintain a balanced sound (the "sweet spot"). Then, you lose some soundstage with that toe-in, so there's a tradeoff.
 

tuga

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Well you do need wide dispersion to the top octaves to maintain a good response off-axis like that and the inverted dome does help to achieve that better than any non-waveguided dome tweeter I've seen measurements for.

I have a similar setup with my S400's and they are almost magical in that sense with the constant directivity but I'm really impressed by what Focal can do with the inverted dome.

With the typical narrowing-dispersion speaker as frequency increases, you need more toe-in to maintain a balanced sound (the "sweet spot"). Then, you lose some soundstage with that toe-in, so there's a tradeoff.

Perhaps with close to 0 toe-in...

But you get sharper phantom images by pointing the speakers towards the listener and using narrow dispersion speakers.
 

Haint

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This has been my experience as well. If you can set up an equilateral triangle with decent speakers the resulting phantom center is so convincing I have actually had to stand up a dozen times and put my ear to the physical center to make sure my stereo source wasn't being upmixed to surround. The effect was strong enough to convince me the AVR's display reading "Stereo" must have been wrong.
 
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napilopez

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Lately I’ve started listening to music at night to help me sleep. My Focal 706’s are toed in slightly and I’m just forward of 90° With listening levels extremely low and loudness on. The stereo imaging is stunning with the feeling of floating in the phantom center, I think Focal’s inverted dome tweeter lends itself to this imaging. Similar to headphones but much more substantial.

Anyway, if anyone has thoughts on this please share.

Well you do need wide dispersion to the top octaves to maintain a good response off-axis like that and the inverted dome does help to achieve that better than any non-waveguided dome tweeter I've seen measurements for.

I have a similar setup with my S400's and they are almost magical in that sense with the constant directivity but I'm really impressed by what Focal can do with the inverted dome.

With the typical narrowing-dispersion speaker as frequency increases, you need more toe-in to maintain a balanced sound (the "sweet spot"). Then, you lose some soundstage with that toe-in, so there's a tradeoff.

Yeah, I agree with this. I think more interesting about the Focals is that their dispersion profile is fairly unique. Typical domes start beaming/narrowing around 6kHz, focal maintains a wide, almost constant-directivity-ish behavior up to about 9-10kHz. It seems to add a sense of scale in the highs

Perhaps with close to 0 toe-in...

But you get sharper phantom images by pointing the speakers towards the listener and using narrow dispersion speakers.

So I largely agree with you, but my overall impression is that a well-controlled wide-directivity speaker can seem similarly sharp to one with good narrowish directivity. (Most wide aren't quite as well controlled as narrower speakers though).

To me the analogy is roughly like watching a movie on, say, a 4K 32-inch monitor vs a 4K 100-inch projector. The same resolution, but spread over a larger image on the latter. So in a sense the projection/wider speaker is less sharp, but the 'resolution' is the same.

I know some people don't quite see it this way, just my own impression. I usually don't really feel like im losing much if any 'resolution' with wider speakers.

There's also the advantage that wider speakers have in reducing interaural crosstalk correlation, though it's hard to quantify quite how much this matters.
 

Chromatischism

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Yeah, I agree with this. I think more interesting about the Focals is that their dispersion profile is fairly unique. Typical domes start beaming/narrowing around 6kHz, focal maintains a wide, almost constant-directivity-ish behavior up to about 9-10kHz. It seems to add a sense of scale in the highs
Yeah, funny thing, I just watched this video of Andrew Jones talking about this exact effect:


Buchardt achieves it with a small tweeter and a waveguide,
Others achieve it with various ribbon tweeters,
Focal achieves it with an inverted dome

Occam's tweeter?
 

tuga

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Yeah, I agree with this. I think more interesting about the Focals is that their dispersion profile is fairly unique. Typical domes start beaming/narrowing around 6kHz, focal maintains a wide, almost constant-directivity-ish behavior up to about 9-10kHz. It seems to add a sense of scale in the highs



So I largely agree with you, but my overall impression is that a well-controlled wide-directivity speaker can seem similarly sharp to one with good narrowish directivity. (Most wide aren't quite as well controlled as narrower speakers though).

To me the analogy is roughly like watching a movie on, say, a 4K 32-inch monitor vs a 4K 100-inch projector. The same resolution, but spread over a larger image on the latter. So in a sense the projection/wider speaker is less sharp, but the 'resolution' is the same.

I know some people don't quite see it this way, just my own impression. I usually don't really feel like im losing much if any 'resolution' with wider speakers.

There's also the advantage that wider speakers have in reducing interaural crosstalk correlation, though it's hard to quantify quite how much this matters.

These questions of perception are hard to pin-point and describe but I have found that narrow-dispersion (in untreated rooms) and/or >50° toe-in increseas "clarity" with orchestral music which results in more "focused/sharper" phantom images and better instrument separation.
The downside is a loss in "spaciousness".

Pick your poison. :p
 

Newman

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The benefit of inverting a dome is to increase the breakup frequency, not to increase its dispersion.

Of course, a company specialising in such products could make a variety of claims.
 

restorer-john

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To be honest I don't think that the inverted dome has anything to do with it.

Just get a few toddlers in your listening room and all your tweeters will be inverted (poked in). ;)
 

Newman

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tuga

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Just get a few toddlers in your listening room and all your tweeters will be inverted (poked in). ;)

:p

Had that happen twice.
Fortunately they were silk-domed and I managed to fix it with a vacuum cleaner.
 

JoachimStrobel

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Lately I’ve started listening to music at night to help me sleep. My Focal 706’s are toed in slightly and I’m just forward of 90° With listening levels extremely low and loudness on. The stereo imaging is stunning with the feeling of floating in the phantom center, I think Focal’s inverted dome tweeter lends itself to this imaging. Similar to headphones but much more substantial.

Anyway, if anyone has thoughts on this please share.
I guess your impression comes from listening in bed. I assume you are not sitting completely upright while listening. Your head transfer function is completely different when sound hits you from your feet.
 
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TankTop

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I guess your impression comes from listening in bed. I assume you are not sitting completely upright while listening. Your head transfer function is completely different when sound hits you from your feet.
My head is directly between the speakers and they are toe’d in a little. It’s a stereo image that I’m in the middle of. You may have a point about the orientation of my head to the speakers though. Stereo imaging is superb but soundstage is a little off, kinda shifts directly right or left of my head with the smallest movement.
 

Ron Texas

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If it works, it's good.
 
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TankTop

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If it works, it's good.
Yeah, I was more or less just relaying a cool effect. Again extremely low volume with loudness on and bass and treble flat. A very enjoyable listening experience to fall asleep to, very enveloping sound.
 
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9radua1

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My overall impression is that a well-controlled wide-directivity speaker can seem similarly sharp to one with good narrowish directivity. (Most wide aren't quite as well controlled as narrower speakers though).

To me the analogy is roughly like watching a movie on, say, a 4K 32-inch monitor vs a 4K 100-inch projector. The same resolution, but spread over a larger image on the latter. So in a sense the projection/wider speaker is less sharp, but the 'resolution' is the same

What a great analogy! Ive often tried to describe the experience with my Eve SC307s (ribbon tweeters) with wide, constant-ish dispersion up to about 8-9KHz. The phantom center is precise, but kind of large. I also have the S400s, and they seem more point-source-like in the phantom center, but can’t provide the same scale “envelopment” and depth-of-field.

It’s like how 4k on a big screen also provides more depth-of-field (“3D”) than the same resolution on a 32” at home. Its as if the information in a larger image surface (or wider sound dispersion) makes our perception “weigh” the information differently, though it’s equally resolved in both cases.
 

Chromatischism

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I also have the S400s, and they seem more point-source-like in the phantom center
I agree with that, they can give a very intimate sound. But due to their bass extension and almost constant directivity to 20 kHz, they can still project a big soundstage. Point them somewhere between straight ahead and crossing behind you so you get the 15-30 degree frequency response which is very flat. I flirted for a bit with them pointed directly at me, but I found them a little too hot in a couple of frequency ranges and it sounded too direct for my liking.
 
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