Comment on My First Home Theater Design (1 Viewer)

[JeffreyS]

I've just completed a draft mental plan for my first home theater. I think I've done my homework well, but this is still uncharted territory. Please take a look at my plan and tell me if there are any problems you see. Thanks!

Main Goal: Maximize A/V performance for movies and music, all at low price. Be portable to new house in a year.

The Room: Usable space is 10'10"Wx15'L. Walls and ceiling are basically white. Floor is wood. There are 2 windows with mini-blinds.

Speakers: Ascend/Hsu 5.1 system. 4x CBM-170, 1x CMT-340c, 1x Hsu VTF-3. This system seems a no-brainer from a price/performance standpoint. Yes, I want mind-rattling bass, so I've picked the VTF-3 over the VTF-2.

Components: Denon AVR-3803 and DVD-1600. I will probably add a HDTV cable or satellite box in the future, but the primary focus now is DVD playback. I may build an HTPC in the future but am still undecided. I almost decided on a Panny RP82 or XP50, but they're getting harder to find and seem to have problems with post-warranty breakdown.

Display: Panasonic PT-L300U on to Da-Lite Da-Snap 52"Hx92"W with High Power screen material. There's DVI in case I ever do add an HTPC. I'll get a black shelf for the projector and suspend it from ceiling hooks with wire. I'll mount the screen to a piece of wood (e.g. 2"x4") and suspend that from ceiling hooks with wire. The screen is going in front of a window.

Seating: Four XL beanbags from beanbag.com on a charcoal area rug. I have a special liking for beanbags, and they're cheap and reconfigurable.

Ambient Light Control: Cheap custom window plugs: a piece of plywood cut to my window size, with white paint on the outside face (minimizes heat), and white eggcrate foam glued to the inside (minimizes sound leakage, hides plywood).

 

[Frank Zimkas]

Other than the Beanbags, it looks like a great setup. I'm just not a beanbag kinda guy I guess.

 

[Bob McElfresh]

Well the beanbag idea DOES get your head level with the middle of the screen - somthing most of us in chairs/couches dont get to do.

Ideally, the tweeters on all your speakers would be at ear-height. The beanbag seats work, with the possible exception of the center speaker. Look into a tilting rack/rubber door-wedges to give the center some angle.

I hate to say it, but the 10 x 10 x 15 room is going to be horrible for sound. You will have 6 walls with a multiple of 5 feet and 4 walls with mulitiples of 10. This is going to give you some huge enhancements at some frequencies.

By plugging the windows to make the wall more uniform, you actually make the problem worse.

For the subwoofer, plan on buying a Behring Feedback Destroyer (BFD) for about $130. This thing is basically a parametric equalizer you put on your sub cable and can be used to tame peaks. Search the Speakers fourm for "House Curve" to find lots of discussion on this.

Short of that, it sounds like a great system. Enjoy.

 

[JeffreyS]

hate to say it, but the 10 x 10 x 15 room is going to be horrible for sound. You will have 6 walls with a multiple of 5 feet and 4 walls with mulitiples of 10. This is going to give you some huge enhancements at some frequencies.

Should I think about hanging some cheap acoustic foam to lessen these problems? Or would that not help?

Room acoustics is something on which I have done absolutely no homework yet. Perhaps I should look more deeply into it.

 

[Bob McElfresh]

Room Acoustics is something of a "Black Art". Unless you are building a new, dedicated room it's usually better to set everything up, then spot-treat to solve problems.

Use a SPL meter (Radio Shack analog - $40) and individual frequency tones to map out the room response. The NCH Test Tone generator can be used to burn your own test-tone CD.

You use acoustic foam to treat for early reflections. But this wont solve the bass reflections from those walls. For these you need either:

- Weight on the walls
- Bass Traps (only somewhat effective)
- Windows/Doors/Heavy bookcases to break-up the walls
- Equalization

The easiest is the Equalization. Use the SPL meter to get the frequency response from about 15hz to 120 hz and then use the BFD device to reduce any peaks you find.

A good book on room acoustics is "Sound Studio Construction on a Budget" by F. Alton Everest. While it focuses on sound-studios, it does discuss the issues & solutions, and includes 2 chapters on home-theater rooms. But read the early chapters first because he does not re-explain everything in the home-theater chapters.

 

[ChrisWiggles]

An even better book would be another book by F. Alton Everest: The master handbook of acoustics. That deals with acoustics in general with regards to room treatments, room dimensions, room design, hearing, sound, studios, pretty much everything. Did I mention it dices? It slices, it chops! And if you buy within the next ten minutes, I'll send you not one, but TWO copies of the same book. Keep one copy in the family room and one copy in the kitchen! You never realize how often you've needed to read about acoustics but COULDN'T until you have THIS book in YOUR kitchen!!

Yeah, that room could be bad with bass, but if you're prepared to spend time placing the sub and using a BFD, and perhaps also bass traps you should be able to get fine bass for the main listening position, if not just decent bass around the room in general. As for foam and wall treatments, keep in mind this really does squat for the bass. I don't see what "weight on walls" would do though... Do a little reading, and be ready for some time spent experimenting and you should be fine. Sounds like you've done your research and have quite a nice system on the way.

Then again, you ARE moving in a year... so I wouldn't spend huge amounts of time and effort and money on this room. Next house you'll probably have more space, better room dimensions, etc. Still, bass traps, BFD, etc will be useful even in a more close to perfect room.

 

[JeffreyS]

Update:

Yesterday, I put my system together and watched a few DVDs on it for the first time. Here's what I ended up going with:

• Ascend/Hsu 5.1 system - 4x CBM-170, 1x CMT-340c, 1x VTF-3
• Denon DVD-1600
• Outlaw 950 pre/pro
• Outlaw 7100 power amp
• Panasonic PT-L300U projector
• Blue Jeans Cable recommended combinations
• 12-gauge speaker cable from Lowes (non-USians: it's like Home Depot)
• APC Smart-UPS 3000
• Ascend's spartan-looking speaker stands (I like 'em)

I listened to Dream Theater's 'Six Degrees of Inner Turbulence' and the 4th movement of Beethoven's 9th symphony and enjoyed both of them. I watched 'The Hunt for Red October' and 'The End of Evangelion' and was just amazed. Of course, since this is my first HT system, I haven't experienced very many other components, but I was still very pleased. I went to another room to do something, and I was actually startled by a sound in THfRO; it was so lifelike that my brain initially thought something had happened in my theater room. Only after a second did I remember there was a movie playing in there.

All that said, my system is still very far from complete. Here's what I'm lacking:

• The VTF-3 is on backorder, so I have no subwoofer right now. All the other frequencies still sound great to my not-very-well-trained ear.
• I ran out of money before I could buy furniture. Current furniture is whatever I could find, which includes several things made of cardboard.
• I also ran out of money before I could buy a screen. Right now I'm using the wall at one end of theater room. It's not perfect, but it is watchable until I get a real screen.
• No calibration or tweaking has been done. I'm saving that for when I actually do have the furniture and screen and when everything is set up more closely to its final positions. There's so much that's going to change as more pieces arrive that it's just not an efficient use of time to start tweaking right now.