Looking for a project - large room, large sound

Re: ericspt

Now that's a beautiful dog!

And a cool diffusor with bottles :cheers:

Still I can see no place for big speakers really.

Thank you, that's Frank. He is a rescue and the happiest dog we have ever seen.

What defines large and where am I going to run into issues? We like the OB idea so I guess what defines large?

The baffles look to be around 2' wide regardless if its a 15 or 18 inch driver?

Would any OB work?

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Any big OB You would have to move too much into the room, it would have become obtrusive.

But I've got an idea of sth big for big sound that might work well in Your room - a long on-wall line array for mids and highs with floor coupled woofers, two pieces per side.
Stay tuned, I'll be back tomorrow.
 
Anytime I have heard Magnepans or electrostatics sounding really good, they were way out in the middle of the room... 1/3 of room depth behind the speaker, 1/3 between speaker and listener, and 1/3 behind the listener. I imagine it would be true for most open baffle designs.
 
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That ratio works well for me, too. and that's how the Magnepans are set in my living room. But I've used other ratios with success. As long as they aren't crowded up against the wall behind them.

If there is no wall behind them, you will lose bass, that's especially audible in the low mid to upper bass regions.
 
Any big OB You would have to move too much into the room, it would have become obtrusive.

But I've got an idea of sth big for big sound that might work well in Your room - a long on-wall line array for mids and highs with floor coupled woofers, two pieces per side.
Stay tuned, I'll be back tomorrow.

imagine sth similar to vintage McIntosh XRT two piece systems, for example:

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...only with:
1) a lower crossover point around 300 Hz using appropriate small drivers for the mid-high on-wall piece (a well researched subject by diyaudio users making one-way line arrays)
and
2) a shorter bass module that would sit close to wall right beneath the mid-high module with the bass driver firing up for better integration

Such a system would fit nicely and inobtrusively in Your room with a genuinely BIG sound guaranteed.

One caveat - You must be ready to equalize. Every line array needs active equalization, and such an on wall/near wall system would need even more of it. Big boundary gains must be compensated, but the dynamic range will be unmatched.
 
Anytime I have heard Magnepans or electrostatics sounding really good, they were way out in the middle of the room... 1/3 of room depth behind the speaker, 1/3 between speaker and listener, and 1/3 behind the listener. I imagine it would be true for most open baffle designs.

If you design an OB system in a particular way, you can put them WAY out in the room if you wish, e.g. halfway or 1/3 or the way is fine. The idea is to design the system so that the "rear" radiation is as similar as possible to the "front" radiation as possible. With the speakers having very similar or identical front/back radiation, you get good sound everywhere in the room and the tonal character does not change as you walk around, even between and behind the speakers.

I have done this with a couple of systems I have built so far. A planar tweeter is perfect for this application, and all other drivers (when carefully selected) can be dynamic/cone types. The approach requires that you do NOT use a fullranger or coax at the top end, and to use very little to no baffle for the midrange and tweeter. Once you get down to the woofer you may need some baffle (like the 2 foot wide one you mentioned, or less) or you can use a larger (15" to 18") driver. Crossed at aroudn 80-100Hz, a separate subwoofer (or stereo pair) in a U- or H-frame will provide excellent bass in a compact form. Closed box subs can also be used below 80Hz if you prefer. The "mains" need to be 3-way.

If you can position the speakers near the middle of the room and away from the side walls by a few feet this would be something that you could consider as well as the conventional "end of the room" approach, for music listening where you are not trying to employ the speakers as a home theater set on each side of a TV.
 
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Graaf - I had thought about both the MacIntosh line array (very big sound) and also Don Keele's CBT which has remarkable power response. The tonal balance doesn't change even if you go down the hall to another room. They area a lot of fun.

But it seems that Parts Express no longer sell the CBT kit nor any of its parts. Too bad.
 
as you have good woodworking skills and enough space so why not build a pair of Linkwitz LX521.4 reference loudspeakers with some Hypex Ncore amplifiers with analog sound processor? LX521.4 is highly regarded and definitely punchs above its price.

Cost...not the speakers themselves but from what I was reading the DSP, Amps required and other things cost more than the speakers themselves.

If I'm wrong that would be an interesting choice.
 
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Yes Graaf, or attenuate - it ends up being the same thing. That's the dirty secret of Open Baffle, the loss of efficiency in the bass. I've heard and built a few OB where the bass losses were ignored for the sake of efficiency. There was no bass. :)

OB needs a strong amp to sound right.
 
Hi, ericspt

From your two picts in post #38, my take is you don't really have much room to work with on the wine rack wall.
I think I'd probably go with line arrays there, like wesayo and many others have built, given the narrow total width between fireplace and hall wall. Especially so, if the table and wineracks are designated keepers.
Tall and straight would work; pretty easy to build and they don't need much in the way of electronics.
The other narrow line alternative, CBTs, don't look like they could fit without getting into the fireplace space. Their backward curvature forces the footprint out into the room.

If it were my room, I'd be thinking about speakers on the window wall just for all the degrees of freedom that space offers...could do about anything there.
CBTs could be a real nice showpiece there. As could any of the great ideas folks have been offering...