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Harman JBL refuses to give spinorama and polar diagram information to prospective HT customers

Chrise36

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The centre image will move according to where you sit if you have a large TV. That is why almost a century ago they invented the centre speaker.
I am using my Pioneer 50" plasma speakers i think imaging is better like this than having the speaker down have not noticed any moving of the centre image.
 
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sarumbear

sarumbear

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@sarumbear
You can't simply cherry-pick a graph to support your point... that is, I can do as well, from the same paper:
View attachment 178986

Exactly what I stated, perfection is possible but comes a at price. Besides that, that level of perfection is usesless when a center is located below the screen anyway.
I'm stopping this discussion now.
I have not cherry picked. I show you the only 2-way MTM example that this topic is about. You are showing me a 6-way active solution, which is not only OT but also ridiculously expensive and complex for a centre speaker solution. Have you calculated how wide the speaker would be? What size TV will you need to fit it under?

The paper is a mathematical exercise that offers no real life, engineering solution.
 

KSTR

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2 MTM with a bit of care wrt driver choice and construction, spacing and phase delta target can easily achieve an (irrelvant) +-1dB systematic additional vertical lobing error, problem solved (well, maybe except max SPL).
 

HooStat

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Besides that, that level of perfection is usesless when a center is located below the screen anyway.
Could you explain this? I am looking at putting my center below the screen and I would like to understand the issue so I don't get the wrong center channel, or place it poorly.
 
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sarumbear

sarumbear

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2 MTM with a bit of care wrt driver choice and construction, spacing and phase delta target can easily achieve an (irrelvant) +-1dB systematic additional vertical lobing error, problem solved (well, maybe except max SPL).
I wonder why the market is full of failing speakers if their design is easy? For some reason not a single MTM that is measured by @amirm or by Erin managed to come near to that. Meanwhile, you are adamant one can "easily achieve an (irrelvant) +-1dB systematic additional vertical lobing error".

I hope someone will hire you so that we can have a decent centre speaker.
 
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sarumbear

sarumbear

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Could you explain this? I am looking at putting my center below the screen and I would like to understand the issue so I don't get the wrong center channel, or place it poorly.
If LCR speaker's acoustic axis are not level the sound will go up and down when it is panned.
 

dasdoing

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I have seen several solutions to the mtm problem in the pro market.
e.g.: https://www.dbaudio.com/global/en/products/series/t-series/t10/

csm_dbaudio-t10-loudspeaker-front-2_543380703e.webp


1642181302475.png
 

ooheadsoo

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yea, I intepreted it wrong thinking they meant a single unit with "point source",
however the horizontal continues to be good in "line" orientation.
you can even say it is better, since it is more constant

View attachment 179062
I wonder how many speakers you need to stack to achieve the line source radiation.
 

dasdoing

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I wonder how many speakers you need to stack to achieve the line source radiation.

this is one only. for stacks PA guys use special software.
I use line source speakers (L+R) in vertical orientation at home (but mine are not MTM, but MMT). while the vertical is limited it is actualy not an issue unless you want to listen to music seated AND standing
 
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sarumbear

sarumbear

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this is one only. for stacks PA guys use special software.
I use line source speakers (L+R) in vertical orientation at home (but mine are not MTM, but MMT). while the vertical is limited it is actualy not an issue unless you want to listen to music seated AND standing
Can you explain more about your MMT design, which I understand to be laid out horizontally on its long side, and has good horizontal (left and right of the centre) polar diagram?
 

dasdoing

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Can you explain more about your MMT design, which I understand to be laid out horizontally on its long side, and has good horizontal (left and right of the centre) polar diagram?

no. I don't have a center (the mentioning wasn't ontopic). I use this speakers as my mains. they are "vertical line arrays" used in small churches and bars. the two "woofers" are 6". they are meant to be crossed with a subwoofer at 120Hz, which is what I am doing. fun-fact: they actualy integrated with my sub better without any aditional high-pass; I just use a low-pass on the sub.
here is one in my room without the grill:

index.php
 
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sarumbear

sarumbear

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no. I don't have a center (the mentioning wasn't ontopic). I use this speakers as my mains. they are "vertical line arrays" used in small churches and bars. the two "woofers" are 6". they are meant to be crossed with a subwoofer at 120Hz, which is what I am doing. fun-fact: they actualy integrated with my sub better without any aditional high-pass; I just use a low-pass on the sub.
here is one in my room without the grill:

index.php
It was indeed off topic.
 

SpaceMonkey

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If this is still investigated, maybe Danley speaker could be a solution for center speaker. They can be pretty wide in coverage.
 

ROOSKIE

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Many likely already saw this though for others here is the SCL-6 tested

Looks great in vertical mode of course to be anticipated.
Horizontal usage is okay if used in a larger space and if you to host extra friends use compact seating that elevates. Such as a row of 3 with a higher row of 3 behind. So a real in home theater.
Hmmm.
 
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