Newbie looking for idea/suggestions for a unque HT speaker

[ssati2d]

Hi all!

Been visiting here a few times and it seemsike a pretty cool place. I'm hoping that someone here can help me with a project I have in mind.

I've recently gone flat-panel LCD and with it came a re-configuration of the entertainment center space in our family room. This space is built into the house and really cannot be modified, but I did 'pretty' it up by making shelfs and drawers and such with some nice Oak plywood. When I did that, I incorporated a separate 'shelf' right under the TV that will house speakers in the future. The future is close now! I want to get started on the front L/R speakers so I can remove the big floorstanders that sit in the room now, in pretty inconvienient locations and my wife wants them gone! The problems with this set up and many and it's certainly not the ideal setup, but it meets the SAF (Spousal Approval Factor) so it will have to do.

So a little about where the speakers have to go: the speaker shelf is 11" tall inside measurement. It is divided across the roughly 50" wide into 3 separate speaker compartments, Left, Right and Center. The three speakers will eventually match (hopefully!), so if that matters, then please keep in mind we need to match the L/R with a center later on (probably as phase 2!). The width on the L/R 'cubbies' is 13" inside. The center 'cubby' is just under 22" wide. So given these parameters as to where the speakers have to go, it really looks like the L/R speakers will need to have the tweeter NEXT to the mid (I'm thinking to the 'outside') instead of above it. Is there anything wrong it doing that? Kinda like an MTM center but with only 1 M. the other side would be a mirror. I also think this would help separate the tweeters more for better dispersion. So that is the first real issue. Second is the actual material selection for the speakers... the whole unit is built from 3/4" Oak faced plywood. How bad would using that plywood as the box sound compared to using MDF? In reality, it would be very easy to add a front and rear baffle to the existing 'cubbies' and they would be inclosed boxes. The 'cubbies' are 24" deep, so hopefully that can help in making up some of the volume. If I need to line the 'cubbies' with MDF, then I'll do so, just keep in mind then that the outside dimensions can still only be 13" x 11".

So, given all the constraints so far, here is a bit more info. Speakers will be mostly just for TV and movies with occasional CD, but not critical listening. There is a decent 12" powered sub in the system and will always be, so that may help with smaller driver selection. Finally, (for now as I know you will have more questions!) I'm not looking to design a whole new speaker, I'd like to just get recommendations on using an existing mini-monitor-type design that can be placed sideways (conceptually anyway) and still sound good. If it helps, room is roughly 18'x18' and sitting area is approx 13.5" in front of TV/speakers. I need something that plays really well off-axis so suggestions on how to 'move' the axis by angleing the front baffles or something.

Anyway, I hope you guys can help me narrow down a design and help get me on my way to a nice DIY HT speaker system.

Thanks,
Bill C.

[Andy G]

Any chance of a picture (of the shelves etc , i mean ?

There may be something one of us will see that might help the situation.

[Jay_WJ]

You posted the same questions at AVS, didn't you?

As Andy said, some photos will help.

It seems that you'll need no-BSC (no baffle step compensation) or very little BSC in the crossover.

Does your receiver have auto EQ like Audyssey?

[Andy G]

Also, some idea of budget might help too.. I mean, are we talking ScanSpeak or something a bit more sensibly priced. ;-)

[ssati2d]

Thanks Andy, good idea, let's see if this works!!

You can see the center channel in the pic... I still haven't figured out how I'm going to get that out as it had to go in from the back and the unit is permanent! Might have to take off some trim...

Bill C.

[Andy G]

The way I see it, the best option would be to do some small line arrays or say 6 x 3" drivers + a tweeter in the middle. Put them in a sort a vertical tube or something, and then put them in front of the white part either side of the TV. If they are white in colour, anduse white grill cloth, you will get reasonable SAF, and the speakers will anchor the sound to the TV.
You will certainly get plenty of horizontal dispersion as well.

[LineSource]

Hi Bill C.

Have you considered using 8" or 10" coaxial speakers for L+R+C? You could purchase vendor coaxials, or build one yourself with narrow metal strips holding a small tweeter in front of a 10" speaker. If your entertainment center is bulid from quality wood, you would not need to put a box-in-box design, but just create front and rear panels to maintain the full volume.

[ssati2d]

Thanks Andy, but the vertical white areas on either side are the framed walls the entertainment 'area' sits inside of. The whole system must reside inside of that space... wife's rule, not mine, but i also have two large dogs and two cats, so having the speakers out in front like that would not be good. You can actually see the right front speaker there in the very right side of the picture where it sits on the outside of the white wall, actually in a hallway which in one of the main reasons it has to go!

For budget, I'd like to stay around $300 for the pair for all the drivers and x-over stuff. I already have a stash of wood and veneers, so don't need to account for that.

Plus, I want to keep it pretty simple. I was really just hoping some of you experts here could guide me to an existing design for a mini-monitor that would work good if layed on it's side or with just a few tweaks!

Jay,
Yes, i posted over there, but doesn't seem like that site gets as much traffic as over here and no one had resopnded after several days. Thanks for the response now here and there! I'm still a newbie at the audio stuff, so not sure what a baffle step compensation in the x-over would be?

As an idea, what would something like the Northcreek Echo be like if it were build pretty much to spec and then placed on it's side in the 'cubby' so that the front was pretty much even with the front of the cabinet?

LineSource,
I'm not familiar with the coaxial speakers and really don't care fo the looks, plus, I really want to build them myself. The cabinet is all 3/4" oak faced plywood, grade B2 if that matters.
Thanks,
Bill C.

[Jay_WJ]

What will be your usual listening distance?

Again, what brand, model is your receiver?

[Andy G]

difficult.
certainly using say a 6.5" with the tweeter next to it probably wouldn't give you the dispersion you mention.

I think the coax idea might be the go..

How much are the Seas T17 coax's over there ?? There are a couple of x-o designs about for it.