Dimensions for "perfect" ht room using Heritage?

[Coytee]

Wife & I briefly talked other day about building again. I told her if we ever did it again, we would START with the HT room and build it to the dimensions that might be considered as ideal as we could come up with. We would then build around that room so we could try to isolate some of the sound transmissions simply by the layout of the house (ie, not have our bedroom on other side of wall, but perhaps the guest bedroom for the inlaws [6].)

Ok, so I was kidding about the inlaws, but only a little.

So, if you had a piece of paper in front of you and your end desire was a HT room with Khorns all the way around (or perhaps also using LaScalas since I already have a pair), how would you do it?

Would you plan for 5.1, 7.1, 35.13? (where do you stop lol)

Once above is decided, my first preference would be Khorns if/when as appropriate, then if needed, use my 2 LaScalas (but they'd have to be buried into a wall opening)

Thoughts/diagrams?

Has this been discussed already? (I've not found it if so)

I'm not talking about REDOING a room, I'm talking about building a house from scratch and instead of making this room as an afterthought, making it the primary thought & designing around it.

The house would probably be single level and be as wheelchair friendly as we could make it.

[formica]

(ie, not have our bedroom on other side of wall, but perhaps the guest bedroom for the inlaws [6].)

Ok, so I was kidding about the inlaws, but only a little.

That reminds me of some Frank L Wright quotes on not making your guests too comfortable... so they don't stay too long.

You've got a lot of ground to cover, within that post... so for

starters I'd recommend looking at general layout. You need to

know lot size and shape... because if I were starting with a clean

slate, I'd look at having a HT "wing". That is, a room which is

joined to your main home through one wall or passage. Perhaps

it's idealistic, but makes isolation much easier... and can be applied

from top to bottom.

As you know, heritage likes big rooms... so a 20foot front wall

is pretty ideal, putting your front seats, 10 feet back. To that

you should have media storage and equipment rooms, as well as a

washroom in proximity. I don't know if this will be a purely

media room, or a multipurpose room, but that'll be quite a few square

feet.

Given the trend to 35.13 ... I'd tend to aim at least the 7.1 if you

will have multiple rows of seating. I'm aiming for it even in my

modest room, as more and more movies offer the encoding, and I will

have two rows.

Do you already have a prospective lot... or just in the very preliminary stages?

ROb

[Coytee]

We're in the VERY preliminary stages.

I see it going two directions. We live in middle of "family compound". My 85 year old Father in law owns 250 acres on the lake that is being salivated over by some developers. We currently have our (deeded) house & land 'inside' this 250 acres.

Direction A: He sells out & she inherits a boatload of cash and will WANT to move away because of all the new neighbors after it gets developed.

Direction B: He does not sell out & she ends up with some land at which point, I'll point her to the very

top of the hill (tallest around) and try to get her to understand the great view we'll have up/down the lake. Nice thing about Direction B is we could build the house while living in current house which would only be 1,000 feet away & down the hill. Furthermore, we could then perhaps rent out our current house & her fathers house while still being local to keep an eye on everything.

My guess is B is what will happen but they (the family) will have to sell the farm to cover inheritence taxes [:@] and we'll move on anyway.

[Chris Robinson]

I think it was Dr Who who said that he'd design a pentagon with Klipschorns in each vertex (each would need a cove to give a 90 degree corner). Interesting thought.

That being said, there are some fundamental room ratios that are good. Try this program and just put in some dimensions. You'll see how the room modes are calculated at certain frequencies (the notes sound louder at these frequencies) and good room sizes spread these nodes out evenly, giving the room a nice smooth response.

http://www.audioholics.com/techtips/roomacoustics/ModeCalculatingroommodes.php

The width and length are all driven off the ceiling height, so start with as tall a ceiling as you can. For a 10' ceiling, you're looking at about a 20' long room that is 15' deep. If you're using Klipschorns, the sweet spot is 10' back from center line of the long wall. You have 5' behind you which will give you some room for surrounds.

If you're using LaScalas, you can put the screen on the short wall and allow for more rows of seating.

Other room ratios sound good too, they just aren't optimal. Be sure not do have room dimensions that are the same (10 x 10 x 10) or are even multiples of each other (10 x 20 x 40). They develop standing waves and are tough sonically.

[colterphoto1]

My advice- forget about the HT room for now and concentrate your thoughts and efforts toward you family living situation and it's future. Land is not being made anymore. Protect what you have if you love it. Perhaps there would another alternative which might involve keeping your current home if you're happy with it and purchasing/inheiriting enough land to insulate yourself from the neighboring communities.

Development of land is a necessary but horrific thing to do to Mother Earth in my book. I lived peacefully on an 130 acre farm owned by my great-grandparents. It was heaven on Earth until the Amish neighbors started a buggymaking shop and I went from peace and serenity to listening to a diesel motor all day, surrounded by smoke from woodburning furnace stoked with vinyl scrap, and listening to blacksmithing and diesel trucks rolling in all day and night. I was 6 miles from the neighboring town, had a pitch black sky at night, but was run out of the county due to a fight over this zoning misuse of the property (there was not supposed to be any manufacturing on agricultural property).

I think it's much more important to discuss your lifestyle, housing needs, views and serenity with family first. That's what's important in life, is costly to purchase, difficult to preserve, and impossible to recapture once it's lost. In the noise pollution game, noise always wins.

Check the Noise Pollution Clearinghouse for more info.

Michael

[Chris Robinson]

Michael, what a bummer [:@]

I've never heard a story quite like that. I agree with your fundamental approach in life. Make the big decisions first, and the others will naturally follow.

He was asking about a perfect HT room. I think it's a legitimate question that can be taken apart from the other big considerations, assuming he gives them the priority. Most of us deal with the rooms that we have acquired with the homes we've bought, then we spend lots of time and money trying to fix a bad room. Pretty tough to do in a lot of cases.

If he does have the opportunity to build a house, just a little thought to room dimensions can go a long way.

Good luck to him and his family. I sure hope they don't have to sell out to the large corporate developer. Nothing will look the same when they're done.

[colterphoto1]

Okay, sorry for the rant about development.

Let's assume a perfect world, where neighbors arene't a consideration, budget only mildly so, and WAF very 'accepting'.

Before getting down to the engineering of room dimensions and acoustical criteria, how about enlisting the lads to brainstorm a list of 'must haves' for this 'perfect' room. There are some questions to be asked first. A practical problem-solving approach, if you will.

Is the room primarily for HT viewing or occasion or often 2 ch listening

Are there other entertainment uses for room (karaoke comes to mind)

Number of people to be comfortably accomodated?

Windows or no windows to contend with?

Easy access to rest of house, or isolated?

Noise transmission to other areas limited

HVAC noise kept to absolute minimum.

Available ceiling height due to engineering specs?

Michael

[Coytee]

*If he does have the opportunity to build a house, just a little thought to room dimensions can go a long way*

That was the essence of my thinking. If there is a (never

achievable) "perfect" goal, then in my view, one can target doable

aspects of that goal and try to come up with their own compromises

given their constraints, be them financial or spatial (or WAF)

[Coytee]

BTW Chris,

My dad lived on HH since about 1974 and about 10 years ago, finally

moved off the island to Bluffton. I'd venture to guess you two

probably know more than one common person (although I probably woudn't

know them)

[Chris Robinson]

BTW Chris,

My dad lived on HH since about 1974 and about 10 years ago, finally moved off the island to Bluffton. I'd venture to guess you two probably know more than one common person (although I probably woudn't know them)

I just moved here this summer (July) but have been coming here since 1982. My mom and dad both lived here before they passed away. It's a really different kind of island that is "small yet large". Lots to do and is a nice community to bring up kids.

OTOH, the traffic in the summer can get a bit overwhelming. Lots of visitors!

I am starting a business here (www.mollymaid.com) and will be opening the doors right after the first of the year. This area is really exploding, especially in Bluffton where your dad lives. When they knock in a few new planned east-west parkways, the traffic should improve. Right now it takes a while to get anywhere.

My office will be in Kitties Landing in Bluffton, right off of Rt 46 and about 1/4 mile from Rt 278.

[DrWho]

The pentagon shaped room was merely an interesting idea and one that I don't think would sound too great considering the kind of reflections you'd get...Also, the ideal system should be a 7.1 configuration. From a few second hand sources it seems Bell Labs did some research in the field of surround sound a long time ago and determined that the absolute minimum speakers required to achieve "perfect" surround sound involves 7 speakers (3 up front and 4 in the rear). Since this is the most that the consumer market supports, this would be the "ideal" to aim for. It should be noted though that movie theatres are using up to 11.3 systems (all discrete), perhaps even more.

I know I mentioned this in another thread, but the most important aspect to a dedicated room is the absence of parallel surfaces. Standing waves and flutter echo's simply cannot occur if there are no parallel surfaces....and these are two of the largest barriers when it comes to acoustics.

So that said, I would start by choosing a cieling height...everything will revolve around it. If you go too tall, you start to lose the homey feel of the theatre and it becomes exponentially harder to "fill the room with sound" (yes, you want a natural reverb in your room). There is something called the "RT60" which is a measurement of how long it takes each frequency to decay -60dB. There is an "ideal curve" that is supposed to represent that which sounds the most natural and pleasing to the ear.

The other consideration you need to take into account, which is directly related to the speakers in question is the minimization of early reflections. An early reflection is pretty much anything that occurs within a 20ms window, which is the threshold of the Haas effect. Because an early reflection is bouncing off a surface close to the speaker, the relative level of that reflection is almost just as loud as the direct sound itself....in the end you get a lot of comb-filtering and a smearing of the image. The best way to minimize this is to flush mount your speakers with a proper toe-in....and to angle the side walls so that these early reflections don't hit the main listening position. It is a trick always implemented in the studios and a quick internet search on recording studios will provide you with all the angles and dimensions that they're using in the studio....which it would be ideal to emulate on a larger scale in the HT. The reason this is directly dependant on the speakers in question is because the dispersion pattern of the speaker will determine the minimum splaying required of the side walls.

Well I think that pretty much covers most of the important acoustical theories involved. Now to put it all into a single design, well.....what speakers are we going to start with? I would love to see a 7.1 system implemented with jubilees all around and an IB subwoofer system (how bout eight 18" drivers?). But that would cost a good $50,000 so perhaps we should start with a budget instead []

Also, how big will the main listening position be? We talking a single couch, two rows, three rows and how wide is each row?