very near field HT surround speakers

[metaldwarf]

Hello World

1st post.

i am looking into building some near field surround speakers for my home theatre setup. i live in a small apartment with little space for speakers. i already have 2 large front speakers and a sub but i would like to add rear speakrs to achieve 4.1 srruound (i very much dislike a center channel so no 5.1 for me) I have been thinking of building something along these lines

http://www.diycable.com/main/product...roducts_id=539

or

http://quicksitebuilder.cnet.com/wrnch2/id47.html

while both are similar and use the same mid driver im debating the merits of the silk dome vs. the ribbon.

i have also been thinking of perhaps a dipole setup similar to this

http://adireaudio.com/Home/KITDDR.htm
again using the same adire extremis mid.

which do you think would prove the best for a rear channel home theatre setup. i have very little space to place the speakers and they would likely be directly next to the couch at ear level. one last note i live with my girlfriend and a female room mate therefore they cant be large or obtrusive and my power to arrange furnature is limited at best.

here are a couple pictures of my room and setup





any recommendations would be very helpful

thanks in advance

Rob

[David Gatti]

Have you considered coaxials? They would be perfect for this setup.
Check these out :

http://www.ele.tut.fi/~artoko/audio/...s/coaxial.html

http://www.soundstageav.com/onhifi/20050901.htm

[AJinFLA]

Someone who shares a small apartment has $2500 USD for rear speakers?
I would imagine David meant something more like this: http://www.madisound.com/cgi-bin/ind...6597&pid=2051.
Or perhaps you can tell me what you do for a living .

Cheers,

AJ

[metaldwarf]

I work as an audio/lighting/theatre tech at the university of victoria center auditorium. http://auditorium.uvic.ca/ i am used to dealing with the likes of EV, EAW, Crown, QSC (hence the sub amp, salvaged DOA from a local night club) 802's are also salvaged, the surrounds were turning to dust i repaired them and they work great though not quite hifi stuff though. great for voice though.

$2500 is a little out of my range but if/when i am ever rich the adire Apex is so the first thing on my shopping list.

anyways im hyjacking my own thread...

the madisounds look interesting i will look into it further. the girlfriend likes the looks of the HT3 by rawacoustics.com though with the extremis near the floor i think it would be wasted and absorbed by the couch. the tower floorstander design of the HT3 is tempting as is the DDR dipole though ~$500 for the needed extremii is a little steep.

do you think that a single extremis 6.8 and the neo3-pdr in the ddr dipole design would provide enough volume. powered by 100W sony (read: 40 "real" watts)

[owdi]

All of the speakers you linked should be superior to those Bose 802s, and all of them would suck as surround speakers. They are too directional for the small space you have.

Imagine you have two people sitting on your couch. The person on the left would only hear the left rear speaker, while the person on the right would only hear the right rear speaker. Try to adjust the balance and you will make on of the people very upset or deaf.

The first thing you need to do is find a way to equalize the distance between the listener and each rear speaker. Your proposed configuration would have one speaker 1.5 feet away from the listeners head, and the other 6 feet. This would amount to a 6db difference in volume.

Wall mounting about 5 feet off the ground will be your best bet. For the speaker, consider a bipole configuration with dual 4" woofers and dual 1" tweeters. This should let you use a relatively small box with wide dispersion and extension below 100hz.

As a side note, how do you get away with having so many messy dishes laying about with two female roommates???? :-)

... eh, now my gf is yelling at me to get off the computer. Gotta run

Dan

[metaldwarf]

As a side note, how do you get away with having so many messy dishes laying about with two female roommates???? :-)

HA those are THEIR dishes so that makes it ok for them to be there. but if i have a single coffee cup oh boy get the riot gear.

Wall mounting about 5 feet off the ground will be your best bet.

can you be a little more specific here?

consider a bipole configuration with dual 4" woofers and dual 1" tweeters. This should let you use a relatively small box with wide dispersion and extension below 100hz.

could you perhaps link to something that would be along these lines. i was hoping to use the adire extremis since ive heard such good things and it just looks "snazzy"

correct me if im wrong but the smaller the diaphram of the driver the wider the beam angle yes? so say all other things being equal a 1" tweeter would be narrower then a .5" tweeter
i seem to remember somthing like that. i think its why bose does the little 3" speakers almost exclusivly

[Cal Weldon]

Hello Victoria,

Beautiful town that is. Yes you are right to assume that the smaller the driver, the better the dispersion, usually.

If you aren't able get a satisfactory distance from speaker to ear, you can consider putting them above your head facing downward. It's a bit different but sometimes it works OK.

[RAW]

Rob
Thanks for the interest in the HT6 as a option .
But as noted for rears I would stay away from such a large speaker as the Kit 61 or the HT6
Why.
Well even in 6 channel format when you use a sub via a reciever the cut off freqency is normally around 80-100 hz.For this reason alone I would lean to a smaller rear speaker.

Now if you had a large room 20 ft wide running 100+ watts into the rears and had room to position them I would lean to the MTM for rears.

Now coming to the point of positioning them.
I helped Danny of GR in the design of the AV1RS this rear speaker fires up and uses the ceiling as a reflection to have a better time alignment in any room if used as rears or as side surrounds.


I would even use a sealed rear speaker tilted back and upward.Far better time alignment to the seated location for surrounds.

Well just my advice.

Enjoy

[Sandy H.]

Al,

Thanks for the post about the upward firing rears. An interesting though and it looks like Danny put together a reasonably priced kit as well. I'm sure the additional challenges when designing the crossover are well out of my ability.

Your last statement mentioned using a sealed rear speaker and tilting back and up. Are you suggesting he keeps a similar position (i.e. height and location at the side of the couch) and simply face the back wall and tilt up at a 30 deg angle or similar? It actually sounds like an interesting idea. I wasn't sure if you were thinking positioning them closer to the floor and up or farther from the wall etc.

Years ago I made the choice (newbie) that I would prefer in-ceiling surrounds than something out in the open. I can heartily recommend NOT doing this unless WAF is the only objective. I have never been satisfied with that choice in my space.

Anyway, I would welcome reading any other comments you may have about the back/up positioning. I'm going to have to ponder the AV1RS a bit more for sure. . .

Sandy.

[RAW]

Position of the surrounds is limited to the room placments that are possible.Height limitations do not matter if you can control the side surround power level output as well as the rear out put.
The key is to have enough power to drive them up firing if they have to be mounted down lower.Really they work the best 12-24" down from the ceiling this is done as well best with a simple string.
Position the upward firing speaker in the height location that is best suited for your room.Window limitations what ever.
Tape the string to the wall location were the speaker will be positioned and run it up to the ceiling and we just use a push pin to hold each string then run it from that spot to your ear sweet spot.
What does the angle look like does the string stretch out to far if so lower the speaker height for mounting.

Really not hard same can be done with a cheap $1.00 laser light and a small mirror.
These tools will get you a lot more out of your speaker placement before you even turn on the source.

Now do they have to be alll the same height for sides and rears NO not if as I said you have enough power to make them work say down low.

Hope this helps out a little.

By the way the blue room is our HT room with the AV1RS on the walls painted the same wall colour.
The cherry AV1RS shows how a simple 45 on the rear of the cabinet then the other piece mounts to the wall.Sitting the speaker flush on the wall.