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Screen Height, Speaker Placement And Seating Locations


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You didn't read my post in full or didn't understand it. I said 5 metre viewing distance, not 5 metre room. 5 metre viewing distance using the 2 to 4 times image height give you a 1.25 to 2.5 metre high screen. Yes these are the extremes. And I did use the 3x image height formula if you re read my post, it works quite well to a point.

I did but you said this:

You will always know your seating position before anything else.
and I want to know how you came to that without knowing the room or screen size?
And that is my point. They all work well enough, albeit having massive extremes, up to a point.

There has to be range because not all rooms are equal. You will have narrower or wider rooms than is "ideal".

Go ahead and use any of these formulas in an 8 metre room. By NOT using seating position and room length only, in an 8 metre room you will get 2.17 metre high image down to 1.54 metre high. (I am using 16:9 as the AR because all projectors have native 16:9 panels, the extra 33% width I have no problem with as this gets one immersion and why scope films are made this way)

2.17 metres high is a native 175 inch image. 1.54 metres is a 125 inch image. A massive difference with large extremes.

Whilst I like a massive image, some do not and why you see people gravitate to the very back row of the cinema or watch a 42” TV from 4m. This part is a personal choice and the idea here is about providing acceptable limits. You would not want a 1.25m screen in the same 8 meter room nor would you want a screen height of 2.5m in the same room. Just because the 2x zoom on their projector allows it does not make it right. The idea of the formula is to allow flexibility within set limits.

Now if you based this on the room length, it means you don't take into account the seating position. What if, the main viewing row is 4 metres from the screen? Not uncommon.

Of course it does. I just work this out from the screen height so it becomes the 3rd part, not the 1st. So if we stay in the 8m room with the 2.17m screen height, the closest we can sit is 4.34 and ideally we would be at 3x or 6.51. Now here is one case where you can not sit 4x (seating between 2x and 4x) because 4 x 2.17 = 8.68m which is longer than the room itself. So if you want to sit 4x the image height you then have to reduce the image size getting closer to the 5.18 end of the range. You don't need to go right to that limit, but you will need to divide the RL by a number over 4 to be able to sit 4x the image height. And more so if you want back surrounds for a 7.1 system and not have your seats on the back wall.

Then if you apply 2.5 to 3.5x image height to 4 metres you get a more realistically sized image which is closer to being correct. 2.5 gets you a 126 inch image and 3.5 gets you a 92 inch image. Can you see how the differences are less extreme? 3x image height at 4 metres works great, gets you a 107 inch image. The larger the screen, the duller the image and the further back one must sit to resolve the image anyway. Further back also takes away some of the immersion and as you said a while back, you re discovered the front row in your room. It's enveloping and immersive.

4m / 2.5 = 1.6m and 4m / 3.5 = 1.42m.

1.6m x 3.68 = 5.88m and 1.6m x 5.18 = 8.28 (this does not fit even in the 8m room).

1.42m x 3.68 = 5.23m and 1.42m x 5.18 = 7.34m

You agreed a couple of years back when I said room length into 4.5 would work well as it's right in the middle of 3.68 and 5.18.

Yes and that was also to cater for the MK3 which needed limits set to the minimum throw range. 4.5 was a nice ‘round’ number that was easy to work with.

Today, throw ratio is the last step I’d be working out. I’d want to know a screen size and seating distance that works in my room first.

In a 6 metre room it seems to work well, gets you a 1.33 metre high image. But again it forgets where the viewer is seated. I realise in an 'ideal' to the thx and smpte spec style room it can work as long as the room doesn't get too long, but so so many rooms are not like this today, something I see almost daily.

6m /3.68 = 1.63m.

1.63 x 2 = 3.26m (closest)

1.63 x 3 = 4.89m (preferred)

I also see allot of floor plans and well as go out to quote homes. Most ‘media rooms’ are less than 6m.

In a 8 metre room it seems to fail, you get a 1.77 metre high image and if you were seated 4 metres away and used the 3 formula you would get a 1.33 metre high image, a difference of 25% in image size here (in fact the difference here is 106 inch to 146 inch, massive). This is my point, projectors cannot light up such large screens, as you said, unless you have 60 grand to throw at a top of the line high output machine. I realise the room contains all the gear but it's the person watching the movie that counts here and this is why I always use seating position first and foremost.

Sorry, I have to correct you there. If you divide the 8m room by 4.5 to get the 1.77m screen height and you sit 3x that height away, you should be at 5.31m not 4m. 4m is about 2.3x the image height.

Lumens are the limiting factor to many HT projectors. This is not an issue with say the BenQ W6000 and even the W7000. It is shame many other HT projectors don’t have lumens to spare and a shame these DLPs don’t have the black levels of the other technology.

Remember Albert's room? 8.4 metres long and we put in a 1.47 metre tall scope screen. If we used room length formula 3.68 the image would have been 2.28 metres high, and 5.18 would have been 1.62 metres high, both well outside the 150 scope screen size (In that room it's room length into 5.71 so that formula wasn't even used..........). Yet his seating position was around the 5.5 metre mark which ends up being 3.74x image height. Front row around 4.0 metres giving 2.72x image height. So for both rows he was within the 2 to 4x image height, the back row falls outside that. Great speakers btw, he loves them.

His room was cool and I am glad he likes his speakers. I think in that case, the limiting factor is the 1000 lumens offered by the JVC projector. If he was able to access a projector like the light cannons from DP then he could have gone larger way larger. I don’t know if the JVC would have actually handled the 1.62m screen, so in this case, it is a matter of having to be realistic towards what the gear is actually capable of.

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Looks like this page hasn't been updated in some time? So I've made up a pdf covering the following:   Screen sizes and formats and how to choose them based on room specs and viewing angl

That's right, realistic and within the performance of the gear. Just look at Dave and Alberts room's, both have 150's, yet both fall outside the 3.68 to 5.18.

Of course, you know the room size before you sit down in it, you don't sit in your chair and then build walls around yourself. You then know where you want to sit before the screen goes in too. There may need to be a walkway at the back for entry etc. Screens always go in last in most setups. Risers, chairs etc all go in before hand, therefore you end up know your distance from the screen before you decide.

2x image height is awfully close. There may be some that sit 3.2 metres away from a 130 inch screen, but I can see SD at 3 metres on a 110 so 130 seems too large at 3.2 metres. 4K projection no problem, you can sit 1.5 metres from a 130 and you wont see pixels ever.

You don't understand what I meant. If the room is 8 metres long, the customer wants to sit or has to sit 4 metres away, then his image size cannot be that large. It has to come down in size to marry up with the ability to resolve the image. I'm not saying you can't sit 5.31 metres away or you shouldn't. I'm saying you can't tell people where to sit, and there are other limiting factors involved as mentioned above.

Most post calibrated projectors are not even close to 1000 lumens, many are 400-700, so size is limited to the projector, then to the viewing distance, then to the room size.

TR is just a number in the end. Required for lenses for the most part. But look I agree, screen size and seating position are the 2 keys and why I use seating position to work out screen size all the time. The room can be whatever length it is, 12 metres or 5 metres. I just find seating position is paramount. Seems logical, it's the person watching the movie after all.

My point is the extremes given don't really help people to choose the correct size. If you said to someone 125 to 175 inch in size, just go in between there somewhere, they wouldn't really know what to do. And why I suggest shaving some off those extremes to get closer to the ideal size. I have no problem with the formulas, I just think they need tightening up a little. That's all.

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I have no problem with the formulas, I just think they need tightening up a little. That's all.

I have been crunching numbers and think if I was to trim them I'd do so from the smaller end before the largest. Maybe start 3.7 (3.68 rounded) and go to 4.8.

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I have been crunching numbers and think if I was to trim them I'd do so from the smaller end before the largest. Maybe start 3.7 (3.68 rounded) and go to 4.8.

For a 6 metre room, and only an example using 3.8 to 4.8

gives 1.57 metre high image x 3 for seating = 4.71 metres which would be quite ideal I think.

and 4.8 gives 1.25 metre high image x 3 for seating = 3.75 metres.

To sit closer with a 1.57 metre high image, x 2.4 = 3.76, possibly sit a little closer at 2.25 x image height you put you at 3.53 which is 1.2 metres in front of the 3x row.

This is 100 to 125 inch image size which I feel is getting closer to the ideal size. Whereas 3.68 to 5.18 gives 92 inch to 130 inch.

It's all rather relative anyway, the bigger you go the further back you need to sit.

Will try this with bigger rooms when I get some time. So 3.8 to 4.8 room division, then base on 2.25 to say 3.5 to 3.75x image height to get seating positions with enough room between rows where applicable. The average of 2.25 and 3.75 is 3.0 so that might just work out well enough.

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I've got 3D modeling software. I am going to start mocking up some rooms and see how big I can go keeping THX recommendation of 15 degrees vertical in mind.

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Right now? Sketch Up. In time, I'll move onto some more advanced CAD program.

Here are some renders on my current room. These are my first attempts at this program, so they may have parts that don't quite look right.

Baffle Wall

Surrounds

So with a program like this, the idea is that one can create any sized room. Sketch Up always begins with a virtual person to provide a sence of scale. There is no reason that "person" can not be moved to replicate a real person in the room. To simulate the seated heigth, you simply push/drag the person through the floor to get their eye line at the desired seated eye line. You can rotate through 360 degrees on all three axis, so you can gain a real world sense of what is needed. And this takes out the limits of real room modeling because now the room can be made as large or as small as required.

I am currently working on a room with double studded walls to show the detail of construction. It is impressive to be able to see how this looks without actually having to build it. 2D just does not give the same visual information.

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For most viewers physical discomfort begins when this angle exceeds 35 degrees. We strongly recommend that the layout of the auditorium adheres to this engineering guideline.

So with that in mind, these are the figures I got when i modeled a room in 3D.

2x IH = 27.5 degrees

3x IH = 18.7 degrees

3.68x IH = 14.8 degrees

4x IH = 14.2 degrees.

In short (assumig you can light it), don't be scared about putting in a big screen :phone:

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Hi Eli, I've drawn them based on a seated eye line of 900mm.

The room I mocked up tonight is based on a 3m ceiling height (who actually has such a room?) with the staggered ratio of 1.0:1.6:2.3 and applied everything the formula in the opening post suggests. It is basically maxed out with the RL being divided by 3.68 and I went from there. What I found interesting though was how the surrounds lined up to be precisely 60 degrees separation with this. I didn't think it would be so precise and expected to have to move them slightly.

I've placed the screen vertically centered which means your not looking up at the screen, rather right at it. My own screen is pretty much the same. Probably too low fro some, but because it is AT, you can optimize both eye lines and speaker heights.

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  • 1 month later...

Hi there,

I am sorry to ask on here but I have read everything I can find and there is so much conflicting information. I am looking at setting up a basic screen and projector until I can afford something better. I think I am pretty much decided on a Benq W1200 and a Grand View screen ( I apologise if this is a substandard setup but t is in my price range). It will be used to watch sporting events on TV, the occasional movie and PS3. I am after some information given my room size. The room is 5440mm long and 3950mm wide and the ceiling is 2830mm high. I would like the projector roof mounted and this can be no closer to the screen than 4000mm as there is raked ceilings. At distances greater than that I have beams that run front to back. Are there any mounts suitable to attach to this? I have trawled the internet and there is various advice and calculators but it is not making sense so am looking for recommendations.

We plan on having two rows of seats if possible. These can be situated anywhere in the room and I will build the back row up around 300mm. the back row is a couch with recliners and the front row is two separate recliners. I would like a fixed screen. Then there is a question of which size and gain.

Do you have any recommendations? Would I be better getting the projector first and then seeing which screen size suits? How do you know how far to have the screen off the ground?

Thanks in advance for any help

Edited by Windoze
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  • 3 weeks later...

I would like to suggest that you can simply follow the steps on the first post of this thread, however this unit appears to be the same as the previous W1000 and has no lens shift and 1.2x zoom, so you may need to actually test this unit if you can't find reliable information as to its projected image size.

If you already own the projector, you can test the size of the image this projector by setting the unit up on a small table or stable chair. Because there is no lens shift, the offset is fixed regardless if the projector is table mounted or inverted. Generally this means that the projector will have to be mounted at the height of the bottom of top of the screen.

If mounted inverted, you will have to ensure that the projector is at or slightly above the top of the screen.

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  • 3 months later...

The Stage is Set

I am about to plunge into this HT thing. I have all of my speakers and subs and processor gear ... now all that is missing is my projector and screen. This thread has been a very interesting read and i can see that both OzTheatre and MarkTecher have contributed enormously to this thread and for that i thank you both. Even though you both might take a slightly different approach i dare say that one is not more correct than the other .. just depends on the application.

In my situation i am a 2ch guy first and foremost and want to get the best possible setup without compromising my 2ch sound. I see that you guys .. well some of you guys are the other way .. ht first and 2ch setup second.

The length of my room is 8.4m with a standard ceiling height of 2.4m. Although i have my 2ch speakers well away from both the rear and side walls now for 2ch listening i am more than happy to re-adjust the speakers when using for ht and put them back again for 2ch.

I am just doing the sums now using both methods espoused by oztheatre and MarkTecher to see which suits my circumstances. I haven't yet decided on a type of projector or screen yet so really open to ideas in that space. I was looking at a high end JVC but open to suggestions. Also open to suggestions re Projector Screen makes. Totally newbie here when it comes to HT.

Have everything except the projector & screen - once i have acquired them i will be in business. So expect me to be asking alot of questions until i get this part sorted.

cheers j

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A few questions / comments:

Do you have complete light control?

You'll only get the benefit of high end JVC's extra contrast if the room blocks all light and is painted a dark colour.

The JVCs have had issues with lamps excessively dimming well before nominal end of life.

How wide is the wall you'll project on?

I'm a fan of Oz Theatre Screens - great performance for a reasonable price.

It would be a PITA to move L&R speakers. How far apart are these normally?

How far is your 2ch seating from the wall you'll project on?

Edited by Quark
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You'll only get the benefit of high end JVC's extra contrast if the room blocks all light and is painted a dark colour.

The room must be completely dark but does not have to be a dark colour to see the obvious contrast advantage of the JVC's. In dark scenes where high contrast and good blacks are really needed room reflections have little influence on results, there has to be significant bright content on screen to visibly affect black level and contrast.

Even though the JVC have much greater native contrast than any of the competition blacks are a very long way from black, even if contrast was 10 times better blacks would still be visibly gray in a totally dark room with zero reflections.

The X70 is an X30 with a second iris in front of the lamp, greater contrast is only obtained over the X30 at the expense of light output. If you want better contrast you have to go to the X90 as it has hand picked and better components as well as more attention to detail paid to the light path. Contrast is significantly better than the other two but it still leaves a lot to be desired IMHO. Maybe one day digital projectors will rival CRT projectors for blacks, but I dont think it will be any time soon.

The JVCs have had issues with lamps excessively dimming well before nominal end of life.

Some peolpe have experienced premature dimming while others have not, its not a generic issue. I'm heading for 900 hours on my JVC and the lamp is fine. I dont need to open the iris fully or use high lamp power so the lamps got life in it yet. I would be quite happy to replace the lamp at this stage in the projectors life if necessary, its a small price to pay for the performance offered.

If running cost is a significant concern other projectors may be a better choice, you dont want to put off using the projector because you are apprehensive about lamp life/cost.

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The Stage is Set

I am about to plunge into this HT thing. I have all of my speakers and subs and processor gear ... now all that is missing is my projector and screen. This thread has been a very interesting read and i can see that both OzTheatre and MarkTecher have contributed enormously to this thread and for that i thank you both. Even though you both might take a slightly different approach i dare say that one is not more correct than the other .. just depends on the application.

In my situation i am a 2ch guy first and foremost and want to get the best possible setup without compromising my 2ch sound. I see that you guys .. well some of you guys are the other way .. ht first and 2ch setup second.

The length of my room is 8.4m with a standard ceiling height of 2.4m. Although i have my 2ch speakers well away from both the rear and side walls now for 2ch listening i am more than happy to re-adjust the speakers when using for ht and put them back again for 2ch.

I am just doing the sums now using both methods espoused by oztheatre and MarkTecher to see which suits my circumstances. I haven't yet decided on a type of projector or screen yet so really open to ideas in that space. I was looking at a high end JVC but open to suggestions. Also open to suggestions re Projector Screen makes. Totally newbie here when it comes to HT.

Have everything except the projector & screen - once i have acquired them i will be in business. So expect me to be asking alot of questions until i get this part sorted.

cheers j

j given you are in the sunny state, why not get mark or oz to pay you a visit for some ideas. dont know if they will....but worth an ask :)

definitely possible to setup a nice 2ch without compromise and ht in the same system with a pj setup, something have done myself, and as per quark I dont think be moving main speakers around. probably better to get a setup so it does both pretty well. in my case am sitting in what corresponds to around 3 image heights to the screen which also happens to be the sweet spot for main listening position for 2ch. so yeah its possible.

its a very deep room you have, what sort of width is probably the important question though. will give you what sort of room width have to work with.

pre pjs, there are other options as suggested by quark to consider. and yes its worth knowing whether you are going for a dedicated room and bat cave, ie total light control, black walls ceilings etc as these will impact quite a bit on end result.is 3D a necessity.

have you had a look at any pj setups in person ? will also help in deciding what suits your needs. re screen and pj. also worth getting a pj first if still bit unsure on exact screen size going for...that way can project up on a wall see what looks like then decide :)

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A few questions / comments:

Do you have complete light control?

You'll only get the benefit of high end JVC's extra contrast if the room blocks all light and is painted a dark colour.

The JVCs have had issues with lamps excessively dimming well before nominal end of life.

How wide is the wall you'll project on?

I'm a fan of Oz Theatre Screens - great performance for a reasonable price.

It would be a PITA to move L&R speakers. How far apart are these normally?

How far is your 2ch seating from the wall you'll project on?

I wouldn't say i have complete light control. It is a dedicated music/ht room that is to say that is all it will ever be used for. Living is done upstairs and my ... errr ... the families ht room is downstairs. The roof is white .. it is a pretty dark room by default. A few windows do exist in the room but i do have permission to cover the windows with heavy black drapes/curtains etc but i won't get away with being able to paint the ceiling black.

To the rear of the room is a staircase leading upstairs which will also leak some light into the downstairs area. There maybe a way i can block this again with heavy curtains around the stair well.

The width of the wall and hence the wall that the screen can fit on is 5.75m. So the room dimensions are 8.4m length, 5.75m wide, 2.4m high

I have a bit of flexibility with the seat. I can move it back or forward wherever i prefer. For speakers i don't want them too close to the rear or side walls for 2ch music purposes.

[quote name=:)' timestamp='1346750306' post='1831041]

j given you are in the sunny state, why not get mark or oz to pay you a visit for some ideas. dont know if they will....but worth an ask :)

definitely possible to setup a nice 2ch without compromise and ht in the same system with a pj setup, something have done myself, and as per quark I dont think be moving main speakers around. probably better to get a setup so it does both pretty well. in my case am sitting in what corresponds to around 3 image heights to the screen which also happens to be the sweet spot for main listening position for 2ch. so yeah its possible.

its a very deep room you have, what sort of width is probably the important question though. will give you what sort of room width have to work with.

pre pjs, there are other options as suggested by quark to consider. and yes its worth knowing whether you are going for a dedicated room and bat cave, ie total light control, black walls ceilings etc as these will impact quite a bit on end result.is 3D a necessity.

have you had a look at any pj setups in person ? will also help in deciding what suits your needs. re screen and pj. also worth getting a pj first if still bit unsure on exact screen size going for...that way can project up on a wall see what looks like then decide :)

Room dimensions answered above - 8.4m length, 5.75m wide, 2.4m high

No i have not seen other PJ setups .. only what i have seen in stores etc.

I am thinking along the lines of a Cinema Scope Screen as it would seem they don't "drop" as low as all the other screens. Yes i am also very happy to consider other projectors ... JVC's are the only ones i have really read up about esp the X90 but very happy to consider others.

Placing curtains in the room not a problem ... painting the roof white will be a problem. Keen to read and learn more about this hobby now.

This has been a hell of a journey getting this far and i can now see light at the end of this very long tunnel .. :-)

Oh i meant to add that i am setup for a 7.2 system. I should look at taking a photo and posting up on here somewhere.

Edited by jrisles
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With a 5.75m wide room you could fit in a 140" 16:9 screen [viewable area 3.10m] or 130" scope screen [viewable area 3.04m] and still leave reasonable room for speakers at the side.

Especially for screens that extend close to the ceiling, the image will benefit from a darker ceiling - doesn't have to be black.

One of the considerations with side L&R speakers that aren't against the wall, is how many seats in each row, so as to avoid those on the ends having their view impeded by the speakers (been through this myself). How many people do you need to seat and is a second row (with riser) an option?

Not sure why the interest in a scope screen. I've got one, but that was driven by a few factors, like fitting the screen above HT L&R speakers. If you want a scope screen without the expense of an anamorphic lens, then it's a choice of one of the JVCs or a Panasonic, as they have lens memories. Note there's a new Panasonic AE8000 due out soon with significantly increased brightness and probably worth waiting for rather than the current AE7000, if you start considering a Panasonic. For actual screen size and aspect ratio you may want to project onto a wall for a week or so before you settle.

The JVCs are capable of lighting up the screen sizes mentioned above if the lamps have a normal life, the projector is mounted with the shortest throw and you use a screen with a gain ~1.2, but probably not much in reserve, especially if you like a bright picture. As I mentioned previously, there have been multiple reports of excessive lamp dimming on the JVCs - check the AVS forums (e.g. one individual on their 4th lamp). There are some reports that lamp life is improved by running the fan in high altitude mode - presumably suggesting it's a heat issue, so may not be a problem for those with good aircon.

If you go with a 16:9 screen the projector options become much wider. If you haven't already, make sure you demo some of the different tech out there and see what you like. Personally, I like the "pop" and crispness of a DLP, but there are also issues like rainbow effects for some people and a little more fan noise than DILA and LCD. The JVCs DILA tech definitely has the best blacks.

A 7.2 system sounds mighty nice. :) Have you settled on the components yet?

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With a 5.75m wide room you could fit in a 140" 16:9 screen [viewable area 3.10m] or 130" scope screen [viewable area 3.04m] and still leave reasonable room for speakers at the side.

Especially for screens that extend close to the ceiling, the image will benefit from a darker ceiling - doesn't have to be black.

One of the considerations with side L&R speakers that aren't against the wall, is how many seats in each row, so as to avoid those on the ends having their view impeded by the speakers (been through this myself). How many people do you need to seat and is a second row (with riser) an option?

Not sure why the interest in a scope screen. I've got one, but that was driven by a few factors, like fitting the screen above HT L&R speakers. If you want a scope screen without the expense of an anamorphic lens, then it's a choice of one of the JVCs or a Panasonic, as they have lens memories. Note there's a new Panasonic AE8000 due out soon with significantly increased brightness and probably worth waiting for rather than the current AE7000, if you start considering a Panasonic. For actual screen size and aspect ratio you may want to project onto a wall for a week or so before you settle.

The JVCs are capable of lighting up the screen sizes mentioned above if the lamps have a normal life, the projector is mounted with the shortest throw and you use a screen with a gain ~1.2, but probably not much in reserve, especially if you like a bright picture. As I mentioned previously, there have been multiple reports of excessive lamp dimming on the JVCs - check the AVS forums (e.g. one individual on their 4th lamp). There are some reports that lamp life is improved by running the fan in high altitude mode - presumably suggesting it's a heat issue, so may not be a problem for those with good aircon.

If you go with a 16:9 screen the projector options become much wider. If you haven't already, make sure you demo some of the different tech out there and see what you like. Personally, I like the "pop" and crispness of a DLP, but there are also issues like rainbow effects for some people and a little more fan noise than DILA and LCD. The JVCs DILA tech definitely has the best blacks.

A 7.2 system sounds mighty nice. :) Have you settled on the components yet?

One of the reasons i was considering a scope screen because it would appear that these screens are wider with a shorter drop? I have only 165cm to play with as a drop from the ceiling to the top of my centre speaker. My L/R speakers are taller but if i can't keep them where they are I can move them to the side of the screen. So this is why i was considering a scope screen. Are you suggesting that a 16:9 screen is "better" or more versatile? I think aesthetically the scope screens look better. If these are "better" but cost more because you require an anamorphic lens then so be it.

I could potentially paint the ceiling black where it is closest to the screen. But not the whole ceiling.

The seating arrangement is for a family of four first and foremost. One 3 seater sofa for the adults and 2x bean bags for the kids. We may look at alternative seating later down the track.

Yes the more i have been reading of late the more i am beginning to think that perhaps the JVC X90 is not the projector of choice. Those Epsons and Pana's get great reviews. I suspect with the imminent release of the Pana 8000 another release of the Epsons are just around the corner too. So i dare say that by the time i have worked out the config of my room there would have been a few reviews released to assist with my decision.

Great idea regarding projecting on the wall prior to settling on an aspect ratio.

With respect to my components they are listed in my signature.

BD = Oppo BDP-95

L/R Speakers = Adam Tensor Gamma

Center = Adam Tensor C9

Rear = Adam Tensor Epsilon

Sides = Adam ARTist 5

Processor = Anthem Statement D2v

Subwoofers = 2x JL Audio Fathom F113

Projector = ???

Screen = ???

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OK, the center speaker height makes a scope screen a good option. I mentioned 16:9 as an option as, if screen width was the only limit, the care required to set up a scope screen is a complication you might not want.

If going with scope without the expense of an anamorphic lens, then you really need the convenience of lens memory that's presently available on only the JVCs and Panasonic.

While projecting on a wall is a good option, I see that Rich at OZ Theatre Screens has a 20% off screens sale at present...

Doh! :wacko: That's what I said when you kindly pointed out the 7.2 setup in your signature. Nice gear! :drool:

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Hmmm ... for a cinema scope i could potentially even go right up to 150"??

It has the following specs

  • Overall size including frame: 3646 X 1625
  • Viewing area: 3496 X 1475

If the border is symmetrical i calculate that to be a drop of 1550. Still within my 1650 tolerance level? How far from the ceiling does it need to be? I am assuming you can't place the border right up to the top of the ceiling? There needs to be a gap between the ceiling and top border of the screen?

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A 150" scope screen will probably fit, the three considerations you may want to take into account are:

1. Whether your projector is bright enough. The JVCs and Pana AE8000 will be bright enough on a new lamp, but I expect the JVCs would need lamp replacement before nominal end of life (putting aside any risk of early dimming).

2. Whether viewers are comfortable watching an image that extends so high.

3. If there's enough side room for your L&R speakers to image correctly.

If you have any cornice, the screen will need to sit below it. Also, the closer the screen is to the ceiling, the more sensitive it will be to reflections off the ceiling. Painting the ceiling a darker colour for a few feet in front of the screen will help.

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A 150" scope screen will probably fit, the three considerations you may want to take into account are:

1. Whether your projector is bright enough. The JVCs and Pana AE8000 will be bright enough on a new lamp, but I expect the JVCs would need lamp replacement before nominal end of life (putting aside any risk of early dimming).

2. Whether viewers are comfortable watching an image that extends so high.

3. If there's enough side room for your L&R speakers to image correctly.

If you have any cornice, the screen will need to sit below it. Also, the closer the screen is to the ceiling, the more sensitive it will be to reflections off the ceiling. Painting the ceiling a darker colour for a few feet in front of the screen will help.

And would add that if zooming then best to zoom the black bars on the wall and not ceiling or on speakers/equipment below and this needs to be considered in determining best scope screen size.

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Thanks guys ... looking at other peope's setups and reading through all the reviews etc i have decided i want to go with an AT screen. I think my room is long enough to build a false wall and put all my gear behind an AT screen which may allow me to go even larger than a 150" screen. Given that i already have an all "Adam Speaker" setup i will just permanently place them behind the AT and the others in their relevant position and will look at acquiring another set of dedicated 2ch speakers in the future to use when i only want 2ch.

This is going to be an exciting project .....

First i will need to treat the front wall then build a frame along the front wall to house the 3 front speakers then the screen etc ... Not being hindered by speakers etc so as to maximise screen size i think is the way to go ... the AT setups look awesome.

cheers Jeff

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Excellent choice! Was going to suggest this yesterday as a way around having the screen too high up the wall, but didn't think you'd be keen from the way you've described the room and the emphasis on 2ch. At 8m deep you'll have plenty of depth still even if you build the false wall out 1m. Happy building :)

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If you're going with the AT screen then to do the whole setup justice you might want to consider:

1. Aspect ratio masking - see here. Chris (Prior) the designer is one of our members here. Note it's available with AT masking as an option.

2. An anamorphic lens so you're not wasting 25% of the projector's brightness on the black bars when in cinemascope (you'll lose a few % in transmission losses, but it's still a lot brighter than zooming). A lens will help you light up a really large screen. There's a couple of local offerings that are both very good, the Aussiemorphic and the Crystalmorphic. I'm running a Mk4 Aussiemorphic (same optics as the Mk5) and am mightily impressed.

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Using an "A" lens will result in a loss of sharpness (MTF), increased distortions and chromatic aberrations for an insignificant increase in brightness.

A good high gain screen will provide much more brightness than a lens could ever provide without the down sides.

If visible pixel structure is a problem a 4k or sudo 4k projector is a better option IMHO.

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Using an "A" lens will result in a loss of sharpness (MTF), increased distortions and chromatic aberrations for an insignificant increase in brightness.

A good high gain screen will provide much more brightness than a lens could ever provide without the down sides.

If visible pixel structure is a problem a 4k or sudo 4k projector is a better option IMHO.

Quite correct Owen, you would know because you use one (A-lens) every day. I don't use my HT anymore because the PQ through my A-lens is so poor. Thankyou again for pointing this out.

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Using an "A" lens will result in a loss of sharpness (MTF), increased distortions and chromatic aberrations for an insignificant increase in brightness.

A good high gain screen will provide much more brightness than a lens could ever provide without the down sides.

If visible pixel structure is a problem a 4k or sudo 4k projector is a better option IMHO.

By an "A" lens i am presuming you are referring to an Anamorphic lens? And therefore you are both suggesting that Anamorphic lenses are not good?

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By an "A" lens i am presuming you are referring to an Anamorphic lens? And therefore you are both suggesting that Anamorphic lenses are not good?

No, only Owen is saying he prefers without.

Quark and Minty have an anamorphic lens and are very happy with it.

I don't use a lens as I zoom. Some prefer an A-lens. Not sure there is a right or wrong, just preference.

If you picked a JVC projector then it has lens memory and will zoom back and forth with a single touch of the remote.

If you pick a PJ without this feature or a PJ with manual zoom...etc and you want a scope screen then an A-lens is the best solution.

Owens preference is to pick something like the JVC ( or maybe only JVC) and zoom as he thinks it is better than using an A-lens.

Edited by bbar
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The optics on the two local A lenses are in some ways better than you'll get in mainstream projectors. Most projectors have some visible chromatic aberration (due to convergence limitations it's harder to pick on 3 chip tech like DILA and LCD, but it's usually there). The local A lenses have no visible chromatic aberration.

The two local A lenses will have some minor grid distortion (invisible to the naked eye, but measurable with equipment) and depending on throw, may have some minor pincushion, which is not visible with a few mm of overscan. With your deep room and a large screen, pincushion would be very minimal.

Edited by Quark
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You will loose brightness with an AT screen, but with the appropriate projector that can be addressed.

Compared to what? Some AT materials have a positive gain so where is the loss? unless you're comparing against negative gain materials?

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Compared to what? Some AT materials have a positive gain so where is the loss? unless you're comparing against negative gain materials?

Each perforation is a non reflective area, hence the non returning light is a sum of those.

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You will loose brightness with an AT screen, but with the appropriate projector that can be addressed.

The perfs of an AT screen will let sound pass one way and light pass the other. Yes there may be some light loss, however I don't consider the 3~5% surface area that holes combine to make to be significant and why I was able to get FL readings as high as 33 from my own system.

Edited by MarkTecher
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Each perforation is a non reflective area, hence the non returning light is a sum of those.

True, but if the rest of the material has a positive gain, it negates the losses from the perf holes to give an overall positive gain.

See here for an ISF test on our acoustic vision. It ended up having the same gain as 2 other leading screen manufacturers non woven vinyls'.

http://www.ozts.com.au/acousticvision_test_results.pdf

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  • 5 months later...
  • 4 years later...
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On 05/03/2013 at 5:47 PM, CAVX said:

I did these diagrams to hopfully better explain parts outlines in Post 1.

The link is to my Blog.

mark, perhaps just a point of note. and perhaps a tad unclear in your diagrams is main listening position location vs depth of room. perhaps am misreading the diagram but it looks like the main listening position is a long way back close to back wall of the room. this is usually not idea due to reflections off back wall causing coherency issues and also not great given room gain for bass tend to get there. In moving between rooms and houses I've always found sitting at 2/3rd room depth to work out ideal. not near the back wall not in middle of the room where there is usually a null.

this would ofcourse place a 2nd row in a compromised location behind...but usually it owed leave enough room behind in most rooms id suggest with 1/3 rd of the room behind the main listening position. also i think works on the principle can make one seat ideal in a setup. rather than have all just a compromise. 

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I based the primary seating at 2x the image height (as I would for CIH) and that places the listener closer to half way of the depth of the room.  Given more people prefer 2.5x to 3x, then they are closer to where your suggesting.  

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6 hours ago, CAVX said:

I based the primary seating at 2x the image height (as I would for CIH) and that places the listener closer to half way of the depth of the room.  Given more people prefer 2.5x to 3x, then they are closer to where your suggesting.  

yeah half way is not a good place to be as guaranteed to be sitting in a natural null for any room. something not even EQ as bandaid will be able to fix unfortunately. but yeah 2.5x-3x even sitting closer i.e. 2.2x comes closer to the 2/3 room length than ending up in the middle :) and all too the benefit of the audio

its always a balance of compromises these things I guess.

 

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