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Hi Guys,

 

Have a few questions for the more knowledgeable. We are having a house extension done and am including a media/theatre room. My main concerns are around prewiring?

 

Room size: 5.9m x 3.8 (projector on 3.8)

 

1) The main issue is how do I prewire if I don't know what chairs I am using yet. Looking to have 2 rows and hence don't know the spacing of the chairs as haven't even decided how large a screen I can go. So not sure on speaker placement.

2) With 2 rows and not knowing distance from screen or row spacing, I don't see how I can get the riser I want also built by the builder?

3) Currently have 5.1 setup, might go 7.1. So with not know chair spacing I also don't see how I could prewire the surround speakers, fronts should be ok?

4) Even the power plug on roof for projector if I don't know distances yet.

 

My thinking is not getting the builder to finish the room then I come in after and try build riser, carpet, and get wiring done. What do you guys think?

 

Lots of questions and any help will be useful.

Thanks

 

 

 

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40 minutes ago, pgjohnson said:

Hi Guys,

 

Have a few questions for the more knowledgeable. We are having a house extension done and am including a media/theatre room. My main concerns are around prewiring?

 

Room size: 5.9m x 3.8 (projector on 3.8)

 

1) The main issue is how do I prewire if I don't know what chairs I am using yet. Looking to have 2 rows and hence don't know the spacing of the chairs as haven't even decided how large a screen I can go. So not sure on speaker placement.

2) With 2 rows and not knowing distance from screen or row spacing, I don't see how I can get the riser I want also built by the builder?

3) Currently have 5.1 setup, might go 7.1. So with not know chair spacing I also don't see how I could prewire the surround speakers, fronts should be ok?

4) Even the power plug on roof for projector if I don't know distances yet.

 

My thinking is not getting the builder to finish the room then I come in after and try build riser, carpet, and get wiring done. What do you guys think?

 

Lots of questions and any help will be useful.

Thanks

 

 

 

projector at 3.8 length of wall ? that means room depth is only 3.8m ? i wouldnt be doing two rows of seating on that ! 

 

as to distances.... work from main listening position at 2.3rd room depth. that puts main listening potion at 3.9m using the 5.9m length. leaving good 2m for 2nd row which can fit in. also leaves sufficient distance to fit in 7.1 and overhead speakers for 7.1.4 easily 

 

as to throw for projector ? I wouldnt have it all ways back at rear wall have it closer to minimum throw. at 3.9m I would be running a 130" screen for immersion at THX spec which will also give some gains for 4k you will need a projector with some serious output though to light up for HDR

 

alternative if using 3.8m depth...well main viewing/listening position is going to be at 2.5m, at that distance thx spec for immersion only demands a 80" or so telly. some folks will just got with a 77" telly or something at that distance instead. others who are immersions fiends might still go a 100-120" screen ! :D and no there isnt enough room for a 2nd row... you can still do 7.1 though id only go 7.1.2 rather than 7.1.4 given the limited room up back...

 

get some help with a local installer if really unawares...sometimes it takes someone coming in looking over with some suggestions, dont go on recommendation of builders...ive seen some shocking end results. use a specialist to help in design of the room if need be,

 

 

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Oops think I wrote it wrong, depth would be the 5.9m.

 

Looking at the tk800m. Main watching is sports with netflix and some PS4 gaming.

 

Was initially thinking 120" screen but now thinking would be great to go 130".

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hmm the tk800M is improved over the 800 but still has no lens shift so you would need to be very very exact with your mounting position or have a vertical and horizontal mount.. can be done from research.

 

here is the throw calculator for the pj

https://www.projectorcentral.com/BenQ-TK800M-projection-calculator-pro.htm

you will see it will be mounted above and to the rear of your first row, based on 1st row at 3.9m. Betty Boop was most likely referring to the epson 9400 or a jvc projector both are way out of your price point. (sorry if i am mistaken)

 

tk800m on special here https://www.ezyhd.com.au/shop/benq-projector-tk800m/

 

anyway if no plan you can still do wiring i guess just leave extra for any changes, sorry i keep wires out of walls, lights off who sees them?

 

riser i would NOT get a builder to do it if you have no chairs, plans etc done. they are not hard to build or find a local person later on. need a good plan inc wiring under, access points, plugs etc... or just keep it a simple box.

 

seating.. do your research as no good buying massive theatre chairs and finding its a tight squeeze. how many people will use the room?

 

screen.. 130" being refereed to would have been for a scope screen i will guess? are sports / netflix in that format or standard 16:9.. when i game its in 16:9 typical HD tv size. i think 130" 16:9 might be a bit big sitting at 3.9m (depends if that is eyes to screen distance) for gaming which includes rapid eye/head movement you might find 120" 16:9 a good size.

 

its great to pre this and that but without knowing what you want it can be a waste. more research needed i think to help you make choices.

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Thanks so much for the advice. Yes, know I will have to be precise with placement with the tk800m, just seems right to me as mostly used for sport.

 

I guess the riser is the main concern with not having furniture yet and thinking if I get the builder to do it or do it myself. Simple box might be the way to go. If 3.9 is the optimal distance a riser from 4m to 5.9m might be ok to plan in advance with the builder? Guess it really depends on final screen size and whether I would ever be closer than 3.9m?

 

Yes, really need to decide on seating, mostly used with 4 people but probably aiming for 6 seats. Most chairs seem as least 90 depth so if riser starts at 4m, back row would be around 5.2m eyes to screen if needing a little walk area in front of chairs.

 

Screen 130" will be in 16:9 format. Eyes to screen would be 3.9m I guess.

 

Thanks for all the help, it is very useful.

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130" . 16:9 starts to get very high, how high is the ceiling?  I  have 130" scope AT screen and  the 16:9 image is close to the floor before I zoom back out. It would put your centre speaker very low if not an AT screen  Is an AT screen an option for you

My 300mm riser is 3.6m back from the screen and 1.5m deep. I sit in the front row. The 3m wide image on a 130" 21:9 screen is about the same as a 135" 16:9.

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Ceiling is 2.4m. 130" height is about 1.62m for 16:9 so guessing screen about .4m off floor and same from roof (might go closer to roof).

Don't think I would go for an AT screen at first setup.

 

So yes just interesting on how far back I start the riser, thats why considering if I do it initially or after I layout equipment.

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hmm we have our own choices to make but for me 130 16:9 is too big for that front row. i would think 120" no higher than say 600mm from the floor. you can tilt the centre speaker up a bit quite easily.

 

start the riser at about 4m and give yourself room to stand in front of the 2nd row chair. problem with using HT chairs is they are too big and take up room.

 

sorry but i would not: get the builder to make the riser, would not buy any screen until you have things set up and projected against a wall for a couple of weeks. there is just no need to buy a screen until you have size tested on the wall.

 

 

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the beauty with screen size and viewing distance ... is if want to go 120" you just move you main listening/viewing position just that slightly closer

 

a 120" screen from 3.65m looks exactly the same and with the same immersion as a 130" screen from 3.9m

 

I agree unless going acoustic transparent screen when you go too big and in 16:9 then main thing that suffers is centre speaker ends up pretty much on the floor or firing at the shins... yes you can angle but sound still comes from down there ! :D dont want that .... 

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1 hour ago, betty boop said:

 

 

I agree unless going acoustic transparent screen when you go too big and in 16:9 then main thing that suffers is centre speaker ends up pretty much on the floor or firing at the shins... yes you can angle but sound still comes from down there ! :D dont want that .... 

I was at a 4K PJ demo a while back, 150" 16:9. The centre speaker could have been a  bit higher but it was nearly on the floor.  As soon as there was speaking in the movie my eyes where drawn down to the sender speaker.  I supose I am used to a AT screen now. 

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this will be a problem with 2.4 m ceilings and a 130" 16:9 screen... a compromise will need to found, most times this is just life. you could avoid this by going an A/T screen but then the compromise will be your budget on the up side.

 

if you look at vids on youtube you will find some ht rooms with the centre on the floor..

 

thats why you dont buy a screen until you are sure what size will work for you, use the wall. but with that pj you have very limited zoom so you will need to allow for changing screen size.. could just go 125" in the middle of both.

 

also if you have a so called matched centre to your fronts (they NEVER are as packages are still based on the old stereo/music set up not HT where the centre should be big/bigger/the same as the fronts. so if a puny 4" driver centre look to change it.

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41 minutes ago, pgjohnson said:

What is too low in your opinion for a centre speaker, think I am looking at around 0.4m off floor currently.

thats firing at your shins :D  doesnt even quite make it to knee level :D 

 

id be looking at 600mm upwards for tweeter on centre speaker .... that likely make stand for centre speaker 500+

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I wouldn't do it but seen where people don't run a centre, just a phantom centre.  When one of my Catalyst amps was being repaired I just had L and R.   It wasn't too bad...

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Is it possible to mount the projector directly to the ceiling? Is it bad to do this?

 

Just trying to gauge a way of increasing the centre speaker floor height and maximising screen size.

 

Thanks

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13 minutes ago, pgjohnson said:

Is it possible to mount the projector directly to the ceiling? Is it bad to do this?

 

Just trying to gauge a way of increasing the centre speaker floor height and maximising screen size.

 

Thanks

yes lots of folk do this. as long as not jus hanging off plaster board. make sure can secure to something structural and use a decent mount and projector that has adequate shift and zoom (not relying on digital keystone correction)

 

also be careful dont go so big that screen is unto ceiling. ... end up a with a crook neck looking up at the screen ! thx viewing angles suggest 15 deg... for good reason. 

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Excellent, thanks for all the info.

 

Yes looking at tk800m which has no shift hence the need to get as close to ceiling to increase floor speaker height. Possibly straight into ceiling with no mount but then brace ceiling above from roof side.

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pj from looking at the manual if you place the benq up against the ceiling there looks to be a "vertical offset" of 162mm for a 130" 16:9 screen ( https://www.manualslib.com/manual/1567087/Benq-Tk800m.html?page=12#manual)

 

so if you have 2400 mm ceilings - 162mm v.offset - 1619 (130" screen height) - 2 border widths (say 100mm each) -200mm = 419mm from floor to bottom border.

 

well thats how i work it out anyway and thats the problem with no lens shift.. the newer tk850 has lens shift that fixes this problem.

Edited by hopefullguy
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yes, thats what I get also. Although vertical offset might be from middle of lens so might have to add half width of actual projector? Border widths I guess if using screen?

 

But centre speaker would be very low then :(

 

Think the tk850 might just be out my reach budget wise though. Projector mainly used for watching sport, netflix and PS4 gaming so the tk800m looked like it was the best fit budget wise.

 

Edited by pgjohnson
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Actually it looks like it not the lens shift (only upwards, down if ceiling mounted) on the tk850 but more the lack of vertical offset that would be better sending image straight instead of down if ceiling mounted.

 

Unfortunately still think the tk850 might be out of budget.

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4 hours ago, betty boop said:

yes lots of folk do this. as long as not jus hanging off plaster board. make sure can secure to something structural and use a decent mount and projector that has adequate shift and zoom (not relying on digital keystone correction)

 

also be careful dont go so big that screen is unto ceiling. ... end up a with a crook neck looking up at the screen ! thx viewing angles suggest 15 deg... for good reason. 

Actually meant projector directly to ceiling with no mount, obviously bracing the plaster board more. Just to be able to raise image.

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1 hour ago, pgjohnson said:

Actually meant projector directly to ceiling with no mount, obviously bracing the plaster board more. Just to be able to raise image.

Not sure how plan to align, projector and screen without a mount ?  which is a major aspect to mount. Or alignment and to any precision :)

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time to look for a high lumen, low lag pj with lens shift.

 

the tk850 is still new, as with all these things prices fall over time. keep an eye out for when Benq aust website starts selling refurbs again, closed due to virus thingy.

 

not sure if the epson ehtw7100 fits your needs, keep an eye on the epson aust seconds web page.

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1 hour ago, betty boop said:

Not sure how plan to align, projector and screen without a mount ?  which is a major aspect to mount. Or alignment and to any precision :)

Ha, ha yes but if I go tk800m I would need to be very accurate but trying to get highest off floor. Planning to just use wall for projection.

 

Basically I am limited with my ceiling height on centre speaker placement if not going with an AT screen it looks like it but at this stage will need to stick with projecting on wall so will have to find the best compromise.

Edited by pgjohnson
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