First ever post - Starting HT project - Help

[rdevans]

Great Forum...I read it all the time and learn more here than anywhere else. Kudos!

I have a room that I am going to turn into a HT. I want to do most if not all of the work myself (except electrical and some carpentry, millwork, and drywall for an equipment closet). I am a fierce reader of the forums, magazines, books, and web articles. Most of the phases of the project seem very managable to me. However, I am stuck in the starting gate!!!

Specifically, I don't know how to design the darn thing. And the whole acoustics topic gives me TIRED HEAD. I am planning on spending about $25,000 on the entire project, spread out over a year or so. I expect to get a lot for that kind of money, but I know that poor acoustics can make the best equipment sound bad. Where do I turn for some advice on this?

Frankly, I am of the mindset that there is so much info out there that I want to ride someone elses coat-tails a bit. Here are the basics of what I have and what I want:

Room is a rectangle, 22'10" long X 11'12" wide X 10' tall
Currently drywall with flat, dark paint
Carpet
3 small, easily coverable windows, so darkness is achievable
Adjacent only to the master bedroom, no rooms above
Want the front speakers flush with the screen, not freestanding in the room
Want at least a 5.1 set up, but more likely a 7.1
Hoping to get 2 rows of 3 seats, and maybe a 3rd row of 2 seats.
Want a front projector, large screen, center speaker behind the screen

Now...

How do I calculate the best place for my seats?
How big should my screen be?
Sweet spots for my speakers? Subs?
Where do my acoustical treatments go?
Is there a computer program for this?
Do I have to pay a pro?


I really am ok with a 90% accurate solution. I'm not a perfectionist in this area, so some basic guidelines would really get me going. This room seems ideal for this, and the deminsions seem like they would make accoustics REALITIVELY straightforward.

Sorry so long...just a lot on my "HT Enthusiast" mind

Ron

 

[Methost]

I am an HT newb myself so I wont offer any advice. But I am sure you will get some good advice from some of our more knowledgeable members. I do look forward to reading your posts on the progress of your project though. I wish you luck as well!

 

[Buckle-meister]

Welcome to the Forum Rdevans.

...the whole acoustics topic gives me TIRED HEAD.

No pain, no gain.

Want the front speakers flush with the screen, not freestanding in the room.

You will lose some sound quality if you do so.

How do I calculate the best place for my seats?
How big should my screen be?
Sweet spots for my speakers? Subs?
Where do my acoustical treatments go?
Is there a computer program for this?
Do I have to pay a pro?

Read.

Regards

 

[Tritonman]

How do I calculate the best place for my seats?

The general rule of thumb is 1.5-2.0 times the screen width

How big should my screen be?

That all depends on the type of projector you buy. My room is 12x28 and I use a 109 1/2" screen. My projector is able to project an image that size with no loss of color or detail. Some projectors begin to have issues around the 96" mark. So it all depends on your projector. The link below will help.

http://www.projectorcentral.com/projection-calculator-pro.cfm

Sweet spots for my speakers? Subs?

Each room is different and certain speakers perform differently than others. There is no set way to achieve a sweet spot. There are guides however..but the best way to do it is use your ear.

Subs generally are put in corners..this yields the "best" performance..this does also tend to create a certain boominess. So you will have to play around with movement to find the best spot for your room.

Where do my acoustical treatments go?

Yet again another question that too many variables based on your room. Generally you want a set behind each front speaker. Bass traps in each corner. A few on the side walls to help with early reflections. You will need to use the mirror trick to find out where your early reflections may be from your front speakers. You may also have to treat the ceiling depending on the room.

Is there a computer program for this?

For room treatment..not really. But there are numerous programs out there that help you measure your room response to see where you are having issues. The link below is a very good free one.

http://homepage.ntlworld.com/john.mulcahy/roomeq/

Do I have to pay a pro?

No. There is plenty of information all over the internet and guides etc to help you on your way. The key thing here is...research..research..research.

 

[rdevans]

Great info...thanks

I will post updates, pictures, and feedback on my experience as the project moves along. The info you are all providing is so helpful. I really want to do as much of this project on my own...seems like the finished product will be more rewarding that way.

We'll talk again soon.

Ron

 

[QED]

With all due respect, you honestly don't sound like much of a DIY type.

You don't want to do the physical work...

. I want to do most if not all of the work myself (except electrical and some carpentry, millwork, and drywall for an equipment closet)...

Or the mental work...

.Specifically, I don't know how to design the darn thing And the whole acoustics topic gives me TIRED HEAD.

And you sound a bit lazy...

Frankly, I am of the mindset that ... I want to ride someone elses coat-tails a bit.

With a $25,000 budget, you should easily be able to afford a pro and get great results with minimal work...

 

[bpape]

I'll take a little different approach to some of the questions.

Where should my seats go? How big should my screen be?
- How many do you want to seat? How big is the room? Those answers will determine the answer to the first question. DO NOT let screen size dictate seating position. That will almost always result in compromised sound. Put the seats where they can and will sound good THEN from there to determine the proper sized screen for those seating positions.

Sweet spots for speakers and subs?
- Every room is different. Don't have your mains stuck in the corners and likely not the sub either. Start out with the mains the same distance apart as you are from each of them at your ears. Tweak from there. This is another reason to constrain screen size. Sub positioning is somewhat trial and error. You can calculate till the cows come home but until you figure in all of the seating, mains position and response, room size and shape, people, etc. - you just won't know. There is almost always a better spot if you're willing to do the trial and error.

Where do the treatments go?
- Some are in fixed positions ( bass absorbers in corners, absorbtion on front wall, scattered absorbtion/diffusion in the rear half, etc.) Others depend on where the seating and speakers are to properly hit the early reflection points (those within 20ms)

Do I need a pro?
- That's really your call. Having someone familiar with acoustics is IMO a good investment. You'll save yourself a lot of hassles and get a lot better performance up front - unless you want to really delve into the whole acoustics thing. As for construction, again, that's up to you. Just also be aware that how you build the room will effect the performance inside the space and the isolation to/from the outside world.