# My Room In A Room



## Mark Techer

This is my 3rd dedicated room and was built in a unique way. Not only did it have to provide me with certain predetermined criteria, it also had to be fully isolated from the rest of the house and in the even we ever sell, had to be easily removable. The solution was to design and build it as if it were a free standing trade show stand. The other challenge was it had to be built to a very tight budget and had to be finished before the lease on a town house I was renting expired. 








Equipment:


AVR - Pioneer VSX1018 THX Select 2. Currently only the surrounds are powered by the AVR. LCRs and SUBs are all active.
BD Players - Phillips BDP3000 (needed for subtitle relocation) which replaced the older Samsung BDP1500.
Projector - BENQ W5000 1080 DLP calibrated to 6500K.
Anamorphic Lens - CAVX MK4 fully corrected cylindrical anamorphic lens.
Curved AT Scope Screen - Modified OzTS using "Acoustic Vision" which is the same as SmX. Screen size is 2250mm x 949mm.
Speakers - CAVX Active LCRs, passive SURs and Active SUB.
4 Seats on two levels. First Row 2x the image height, Back Row 3.2x the image height.
Acoustic Treatments - Sound absorbing (1st 1/3rd and half of back 2/3rds). Diffusing vacuum formed tile.
Colour Scheme - Black and Grey providing almost total Light Control.


----------



## Zeitgeist

Mark Techer said:


> ... also had to be fully isolated from the rest of the house and in the even we ever sell, had to be easily removable. The solution was to design and build it as if it were a free standing trade show stand.


So, is it literally built and framed as a stand-alone room, and the outside room structure is untouched? (and you can tear down w/o permanent damage.)

Not much experience with free standing trade show stand construction... but I assume it's structurally stable as a standalone room?

Great setup by the way.


----------



## Prof.

A nice set up and some nice gear Mark..:T

Is there a particular reason why the rear surrounds are so close together..With the drivers facing each other and being that close, wouldn't that cause some interaction?


----------



## Mark Techer

Zeitgeist said:


> So, is it literally built and framed as a stand-alone room, and the outside room structure is untouched? (and you can tear down w/o permanent damage.)
> 
> Not much experience with free standing trade show stand construction... but I assume it's structurally stable as a standalone room?
> 
> Great setup by the way.


Thanks, we like it 

Yes it is completely isolated and free standing. There is at least 75mm (3") between my HT and any wall on the house. I have been allowed to build in the garage on the proviso that I also make my dearest other half (soon to be wife) a craft room. So given that I was on a tight budget, I elected not to make a new larger screen and to use what equipment I already had. So why this project only takes up half the double garage. 
You'll notice the ceiling on this room is low. It was done for two reasons -
1. Because I needed to stagger the L/W/H ratios as I didn't want the ceiling height being the almost the same as the room width. As it is, I did have to compromise there anyway as the mathematical ceiling height was only 1700mm and even I am taller than that, so I made it 2000mm.
2. It also had to fit under the panel lift (sectioned) electric door which is still in place until I get the rest of the space sorted.










The floor was the first stage (done in two halves) and it too does not touch the walls (except for cover strips once I sheeted) of the cinema. This now allows me to run the sound system at 00dB REF and not have annoying rattles and other vibrations. You can feel the subs through the floor but those vibrations don't transmit through the walls. 

Construction is fairly simple if you know how to build a wall (top plates/base plate, studs etc). So what I did was make frame parts on the floor first and then stand them up. Corners require extra timber to extend their length to allow the adjacent wall to be attached. I drilled right through these extra timbers and used bolts so that I could undo the walls later if required. This also allows me to tighten the joins should over time there be movement. 

The real challenge is thinking ahead when you sheet up on a project like this so that you don't go screwing the sheeting across the join because once you fill the screw holes, you ain't getting the screws out and your only choice then would be to run a saw though the wall to get it apart. Once I had 4 walls up, the ceiling frame was made larger and was simply lifted up and slide from one side. I actually assembled this entire room on my own with no help. 

Sheeting the ceiling was fun. I ran some long 5mm alloy angles and screwed them into the side studded walls so I could lift the sheets and rest them on the angles. I them applied the glue and worked my way along in stages. They were heavy and I got there in the end :clap:


----------



## Mark Techer

Prof. said:


> A nice set up and some nice gear Mark..:T
> 
> Is there a particular reason why the rear surrounds are so close together..With the drivers facing each other and being that close, wouldn't that cause some interaction?


If you go into the set up menu of the THX audio system, you will see that the distance for Back Surrounds is 0~3 feet and centre to centre of my speakers is 3 feet. Because they are spaced, discrete 7.1 audio like Toy Story 3 still works. The speakers are bipolar so their drivers are all in-phase anyway. You'll also notice I added a nice big diffuser between them and this certainly breaks up the sound between them.

I made a jig out of layers of 25mm MDF and then had a plastics company vacuum pull the tile for me from ABS. Pretty cool :sn:


----------



## Mike Ronesia

Interesting concept. How does the room handle the LF?


----------



## Mark Techer

Mike Ronesia said:


> Interesting concept. How does the room handle the LF?


I've not measured it with REW yet. It is not boomy though unless your standing in a corner near the EQ Rack. 
I am of the belief that if the system does not draw attention to itself, then it is set up as good as it can be. I can honestly say that I relax and enjoy the films now and don't think about the sound system. Anyway, for what this room cost, I am not complaining anyway.


----------



## Mark Techer

The latest upgrade to my room - the new Aussiemorphic Lens MK5. This replaces the MK4 as my anamorphic lens in front of the BenQ W5000 DLP projector. This lens is HUGE at about 210mm dia. When I was using the MK4, I have a sled mounted from the top plate to hang the MK4 upside down in the light path. Given the size of this new MK5, I have added a shelf about 100mm lower than the shelf the projector sits.
NOTE: The lens in this image is my prototype and not an actual production unit.


----------



## Ile

Looking good!

Extruded rubber isolators or hard mineral wool strips under floor joist would decouple your room even better from concrete floor.


----------



## Mark Techer

I wanted rubber under the floor. Unfortunately at the time of the build, I was on a very tight budget, so something had to give. I have given thought to a retro as the floor could be lifted, though it would be a pain to do.


----------



## Prof.

The lens looks very a short, or is that because it's so large in diam.?
Is that the new focus ring fitted?


----------



## Mark Techer

The Mk5 Lens is different to the MK4 because it contracts in or expands out, where the MK4 case is fixed (130mm) with the optics moving inside (total travel -15mm). Because the throw (not just the throw ratio) dictates the final spacing between the lenses, the MK5 can be as short as 100mm or as long as 150mm. The diameter of the focus ring is about 210mm, so yes, it is a large lens.


----------



## Jasonpctech

Here's a silly thought.
How about using a design like this for Shipping container theaters. Imagine selling drop on location finished to spec add your own electronics containers with some house siding to look pretty in the backyard.
For the most part heating would be good off the electronics cooling and ventilation would however be designed in to. I see a industry born.
I get american rights to that one.


----------



## Mark Techer

Jasonpctech said:


> Here's a silly thought.
> How about using a design like this for Shipping container theaters. Imagine selling drop on location finished to spec add your own electronics containers with some house siding to look pretty in the backyard.
> For the most part heating would be good off the electronics cooling and ventilation would however be designed in to. I see a industry born.
> I get american rights to that one.


Not such a silly idea if you can add the door to the side not the back. The idea was raised a few years back and lightning storms was the cause of concern. My room certainly proves the idea would in theory anyway.


----------



## Jasonpctech

Mark Techer said:


> Not such a silly idea if you can add the door to the side not the back. The idea was raised a few years back and lightning storms was the cause of concern. My room certainly proves the idea would in theory anyway.


Just ground it well once placed and you make sure all interior surfaces are covered then you have a EMP proof Faraday cage!
if you make the right foundation it could even be a storm shelter.lddude:


----------



## Mark Techer

Jasonpctech said:


> Just ground it well once placed and you make sure all interior surfaces are covered then you have a EMP proof Faraday cage!
> if you make the right foundation it could even be a storm shelter.lddude:


EMP proof? Really? WOW. I want to build one now  Just where in the yard do I put a sea container :blink:


----------



## Prof.

Actually a container wouldn't make a good HT environment..They are usually 20'x10' which acoustically speaking is not a good size..


----------



## Mark Techer

Prof. said:


> Actually a container wouldn't make a good HT environment..They are usually 20'x10' which acoustically speaking is not a good size..


20 long, 10 wide, how tall are they? I agree, 20 and 10 is not a good start anyway... 

If you were to do this, you wouldn't use the full volume for the main room anyway. You would have to build false walls and pack the cavities with fibre wool to change the internal dimensions of the container. This is one environment that might even require the ceiling to to sloped down as well. 

What would be cool is to build a large shed, line that, then build a room in a room (sitting on rubber) inside that. It is just $$$$$ that keep me from my dream


----------



## Prof.

Mark Techer said:


> 20 long, 10 wide, how tall are they? I agree, 20 and 10 is not a good start anyway...


Not sure..but I think they're less than 8' tall.. 



> If you were to do this, you wouldn't use the full volume for the main room anyway. You would have to build false walls and pack the cavities with fibre wool to change the internal dimensions of the container.


Agreed..I think you can buy them with the door and windows already fitted.. 



> What would be cool is to build a large shed, line that, then build a room in a room (sitting on rubber) inside that. It is just $$$$$ that keep me from my dream


That would be big dollars!..Good size sheds aren't cheap!


----------



## Mark Techer

Building a fully isolated home cinema with air cavity around the main room was never going to be cheap. I did mine on an incredibly low budget and saved because I did all the work myself, so my costs were my time and materials. The project would never have happened if I have to pay for labor.

Cost aside, how cool would it be to actually make a shed into a cinema? I met a retired film projectionist a while back that converted his "barn" style shed into his home cinema. The image was not the brightest because of the sheer size (over 2M tall), but it was very cool. He lined the metal skin of the shed, and that was the limit of sound proofing he went to. Whilst his equipment was not up to the task, the idea was good and it showed what could be done if one was prepared to just take a step out the "square" of convention and popular belief. I admire people like that.


----------



## Ile

Mark Techer said:


> Cost aside, how cool would it be to actually make a shed into a cinema? I met a retired film projectionist a while back that converted his "barn" style shed into his home cinema.


I have also visited in home theater made in shed. Very cool place, we watched top gear from sauna and took few beer in Mad Cow Bar.
http://www.dvdfreax.com/theater/october2005/index.php


----------



## Mark Techer

Ile said:


> I have also visited in home theater made in shed. Very cool place, we watched top gear from sauna and took few beer in Mad Cow Bar.
> http://www.dvdfreax.com/theater/october2005/index.php


15 seats? I am so green right now


----------



## Ile

Mark Techer said:


> 15 seats? I am so green right now


Mee too, my about 3m x 5m four seats theater project feels so small after visitin his place.


----------



## Mark Techer

Ile said:


> Mee too, my about 3m x 5m four seats theater project feels so small after visitin his place.


Ahh another cosy room, just like mine


----------



## Jasonpctech

Yea, I guess In my head the challenge was to build one that you don't leave behind if you move.:scratch:


----------



## chrapladm

"A shed into a cinema," that sounds familiar. I have been ever so slowly planning my HT in a newly built shed.

My HT room will start of being 5m x 4.5m x 2.8m. But I do have to make sure there is enough room for 6 people to watch movies. Might just have a small row of cinema chairs in the second row but have to be able to play Wii in the front row.

Nice build Mark. It is even more nice to see such a small HT room because all of the other larger HT rooms I have scene just remind me of how far away I am from completing mine.:T:bigsmile:


----------



## Mark Techer

Jasonpctech said:


> Yea, I guess In my head the challenge was to build one that you don't leave behind if you move.:scratch:


Should be ever sell, my room can be dismantled and moved out, then re-set up in another room. I designed it that way after a rather severe learning curve in 1996 when during the sale of my first house, the buyer insisted that I change the lounge room back. It caused me a massive upset and in the end the buyer paid contractors to do the retro-fit because I would not. Lessen learned was that not all people appreciate a HT. So why this "room in room" was done the way it was.



chrapladm said:


> "A shed into a cinema," that sounds familiar. I have been ever so slowly planning my HT in a newly built shed.
> 
> My HT room will start of being 5m x 4.5m x 2.8m. But I do have to make sure there is enough room for 6 people to watch movies. Might just have a small row of cinema chairs in the second row but have to be able to play Wii in the front row.
> 
> Nice build Mark. It is even more nice to see such a small HT room because all of the other larger HT rooms I have scene just remind me of how far away I am from completing mine.:T:bigsmile:


Thank you for the positive feedback. A part of the room's design was size where I wanted to max out the screen I already had to have that wall to wall look. Although small, when seated, the room feels much larger.


----------



## chrapladm

Just wondered abut the shed walls. Is there some sort of foam to spray on the walls before adding interior gyprock walls?

I was thinking that if I use everything I can to isolate the low frequency some might still get through and that would vibrate horribly on the metal shed.

And where can you find info on your lens Mark?


----------



## Mark Techer

chrapladm said:


> Just wondered abut the shed walls. Is there some sort of foam to spray on the walls before adding interior gyprock walls?
> 
> I was thinking that if I use everything I can to isolate the low frequency some might still get through and that would vibrate horribly on the metal shed.


There is a 2 part rapid expanding foam that you could use. You mix parts A and B and within seconds, it expands to some 10x the original volume. 



> And where can you find info on your lens Mark?


MK5 Lens


----------



## Mark Techer

UPDATE:

I added a Projector Station [top image] to my room. This has made set up and alignment much quicker and easier.

The Projector Station is 2 plated (laser cut from 6mm aluminum) that allow threaded adjustment for height, tilt, pitch. The base plate also allows yaw. The top plate is beginning to look like Swiss cheese because it is compatible with over 20 different HD projectors. Mine [bottom image] does use the slide as I don't move the A-Lens out of the light path.


----------



## Jasonpctech

As always Mark your projects never cease to amaze me. Once I grow up and get a big boys sized HT room I will go projection and hope to incorporate some of your kit.


----------



## Jasonpctech

And, BING! 200 posts.:yay2:


----------



## Mark Techer

Jasonpctech said:


> As always Mark your projects never cease to amaze me. Once I grow up and get a big boys sized HT room I will go projection and hope to incorporate some of your kit.


Thanks  I've come along way from the DIY approach of a few years back. All these products have involved professional industrial design and then I have had to make decisions about the final design to ensure I keep within a set budget.

A for the room size, I'd say my room is testament that the room itself need not be "big".


----------



## patchesj

Curious if you've taken any REW measurements? I'd be interested in seeing your decay graphs and what the low end roll off looks like. I would guess your low end has a ton of room gain.


----------



## Mark Techer

No not yet. If you place your head in a corner, yes, it physically moves you. At any of the four main listening places, no it is not offensive at all. Measured results will be interesting. Though I am not that concerned because to me (and many others that have heard it), the room and the sound system sounds good. I've had a variety of different people come in and listen and none have complained. Many have praised the system/room. When it comes to my room (or any of the things I build) I take criticism as constructive, not a negative, so would make a change if someone could identify a serious problem. And I don't think they are all just being polite. 

Laurie Ficham (spelliing?) from THX said recently on part of an hour long doco on the new THX sound bar and HT room treatments, "our ears do not hear the same way as a microphone measures, and sometimes we need to behave ourselves". It was a very interesting comment (given his audio and technical history). 

I have a friend with REW who measured his room and then applied treatments based on the measurements. This guy spent some serious coin and his SVS sub really does not deliver like it should or like I have read on forums. Every time he comes over to my place, he comments about how he likes my subs. He says that they are deep, low, punchy and clean. I think in all honesty, he over damped his room and created bass losses due to too much treatment (absorption) from his 4 huge bass traps. My main concern in my room was controlling mid and high frequency reflections that cause slap echoes. As mentioned, I have no slap echoes at the screen end of the room. I am using a Pioneer AVR (as pre-pro for the active LCRs) and it features the auto EQ which does not change the sound that much from turning it on to off. This tells me that I have done a reasonably good job. Graphs to come.


----------



## patchesj

I wasn't doubting that it sounds great, actually the opposite. Smaller spaces tend to be easier to deal with on the low end, at least my experience.


----------



## Mark Techer

I guess making bass work in a room is about position of the source (the speaker itself), the location of the listener and the volume of the room. Typically a 50Hz wave is over 22 feet (and they get longer the deeper you go), so you then get a combination of reflected and reverberant waves which can either partially cancel or sum with the primary wave. And this happens on all 3 axis - something the early car enthusiast (early 1990's) never seemed to grasp. 

So wall material pending, that 22 foot sound wave might just keep going. This tends to happen when you have large sliding glass doors in a room. Deep bass tends to pass through it like it was not even there. In my case it braced MDF which is fairly dense. 

I am prepared to experiment with some form of foam corner trap, I just have not been in the situation (or right location) to make it a priority. The diffusing tile was a case of exactly that - being in the right place at the right time to hear the nasty reflections. Researched and solution found and problem appears to be fixed now though I do want to add more of them because I think I can make the surrounds sound even better.


----------



## Dallin

Great sharing!!one of my friend tell me about this thread and i see is really good......it's looking nice setup....Thanks for sharing this.I like it.


----------



## patchesj

Right place, right time, research, build, test, repeat... Seems to be the mantra of DIY enthusiasts like us. I haven't had an opportunity to experiment with small volume, isolated rooms yet. Hence my curiosity. The closest thing I have worked on would be some of those crazy car audio systems you mentioned..  Of course back then I was an audiophile converted to mobile audio and no one could understand what I was trying to accomplish. Imaging? Sound Quality?? Just make it go boom... Eventually IASCA adapted its focus, but car audio manufacturors never really caught up when it came to bass mangement. The typical car environment is very challenging, much more so than the average home theater. Perhaps that is what pulled me into it.


----------



## Mark Techer

patchesj said:


> Right place, right time, research, build, test, repeat... Seems to be the mantra of DIY enthusiasts like us. I haven't had an opportunity to experiment with small volume, isolated rooms yet. Hence my curiosity. The closest thing I have worked on would be some of those crazy car audio systems you mentioned..  Of course back then I was an audiophile converted to mobile audio and no one could understand what I was trying to accomplish. Imaging? Sound Quality?? Just make it go boom... Eventually IASCA adapted its focus, but car audio manufacturors never really caught up when it came to bass mangement. The typical car environment is very challenging, much more so than the average home theater. Perhaps that is what pulled me into it.


The very first "small room" I did was in 2000. I converted a tool shed that had been built onto the back of the house I bought. I stripped out the walls, packed the cavitied with firbe glass and foam and re-sheeted. After I was done, the room was small at just 3.6m x 2.4m x 1.8m. My logic was if they can a location truck to mix 5.1 audio, then why could I not also use a small room? 

I knew very little about acoustics (not that I am expert now) and worked out quickly that I needed to treat my first reflection points. I did this with a laser (an idea M&K were selling - their product had a suction cup and you stuck that to the baffle of the speaker, then aimed the speaker at the listening position). It made a difference, but not to the level I have today. 

The idea of the full first 1/3rd, half back 2/3rds actually came from information I obtained from a couple of guys that were about to go to Lucasfilm to do the 4 day THX training (back when it was held at "the Ranch". One of the guys really didn't care and said he'd read the info on the plane and allowed me full access to it. I took full advantage of the situation to learn as much as I could. I still have a copy of the notes somewhere. 

And about those car audio systems, my goal was more about high SPL rather than imaging. I never really got to the front end of car before I turned my attention to HT, but the rear deck was a 3 way active system using 6 amps. It played at over 121dB and a friend built a similar system that pegged the SPL meter at 126dB, so we were never able to measure his system.


----------



## H_Roark

Wow, very intense build man. I like the detail in getting the sound leakage to a minimum. Speaking of car audio, my GMC Jimmy is running at 148db right now as my daily driver, one JL audio 13W7 sub in a large box with 1000 watts to it. I'm converting two JL 13W6 subs to be my new theater subs. I'm hoping for some serious boom there as well. Thanks... Roark


----------



## Mark Techer

H_Roark said:


> Wow, very intense build man. I like the detail in getting the sound leakage to a minimum.


Thanks H_Roark. I am very happy with the way it turned out. I bought some of those interlocking foam floor mats in grey the other week (for packing lenses) and used two of them under my subs. I could not believe how much better that has made them sound. Much tighter now. The 4 tiles cost a whole $17.50. So a while ago (I think in the Baffle Wall thread) we were discussing what rubber to use under the speakers and it seems that anything that absorbs sound will make some improvement. The mats THX use cost about $70 each. 



> Speaking of car audio, my GMC Jimmy is running at 148db right now as my daily driver, one JL audio 13W7 sub in a large box with 1000 watts to it. I'm converting two JL 13W6 subs to be my new theater subs. I'm hoping for some serious boom there as well. Thanks... Roark


148dB is scary stuff. Sounds like an awesome project.


----------



## Prof.

Mark Techer said:


> I bought some of those interlocking foam floor mats in grey the other week (for packing lenses) and used two of them under my subs. I could not believe how much better that has made them sound. Much tighter now. The 4 tiles cost a whole $17.50. So a while ago (I think in the Baffle Wall thread) we were discussing what rubber to use under the speakers and it seems that anything that absorbs sound will make some improvement. The mats THX use cost about $70 each.


Mark..Was that the EVA foam floor mats from Clark Rubber that you used?


----------



## Mark Techer

Prof. said:


> Mark..Was that the EVA foam floor mats from Clark Rubber that you used?


No. These were a pack of 4 for just $17.50. I bought them to use as light weight packing for lenses that I had to ship, but ended up using just one tile cut into 4 sections for the lenses. The rubber appears to be similar to that used in those "water walker" thongs (flip flops for the US guys :bigsmile: ) with a harder wearing surface on each side and a softer inner core. The sheets are grey and interlocking and cover about 1200mm x 1200mm. I've got a pair joined and they are working well under my subs right now.


----------



## Prof.

Thanks for the link..Interestingly it does appear to be the same foam as the Clark rubber ones..
From the Bunnings site "12mm shock absorbing high density EVA foam "..Same thickness and type as the CR one's, except these are a lot cheaper and bigger than the CR one's!..
Are you using just one thickness under the sub?


----------



## Mark Techer

Prof. said:


> Are you using just one thickness under the sub?


Yep, one under each sub. I've joined them and used the side strips to make the edges look nice.


----------



## chrapladm

I forgot to ask are these stable enough under the subs that I can put a speaker on top of the sub?

I would think so but wanted to know what you thought. My subs will be very heavy and braced alot so there wont be to much movement or any movement at all. But better to be safe than sorry.


----------



## Mark Techer

chrapladm said:


> I forgot to ask are these stable enough under the subs that I can put a speaker on top of the sub?


If I was to stack my LCRs on the top of the SW, I'd place more of the same rubber mat under the LCR speakers.
They came as a set of four, I used one for packing and still have one spare. 



> I would think so but wanted to know what you thought. My subs will be very heavy and braced alot so there wont be to much movement or any movement at all. But better to be safe than sorry.


The subs may be braced, but quite often, the room that houses them are not, so you still need to isolate vibrations they send out to prevent rattles. I think these represent good value for money.


----------

