Hello there,
OB speakers are mostly lighter and flimsy in structure compared to boxes. So, when playing loud, it seems they are inevitably vibrating some more.
In my own experiences, totally suspended (on a swing) is the best in eliminating vibrations. The second best is softy supported -- the softer the better.
What's your experience on that?
OB speakers are mostly lighter and flimsy in structure compared to boxes. So, when playing loud, it seems they are inevitably vibrating some more.
In my own experiences, totally suspended (on a swing) is the best in eliminating vibrations. The second best is softy supported -- the softer the better.
What's your experience on that?
Ive made a Video with pictures showing me and my friends Speaker:
https://www.youtube.com/watch?v=llLS_k0QwOY
What do you think about it ?
https://www.youtube.com/watch?v=llLS_k0QwOY
What do you think about it ?
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Marine, you have have found the correct base of operations!
http://www.diyaudio.com/forums/pa-systems/41402-powerful-speakers-outdoors-7.html#post2798049
http://www.diyaudio.com/forums/pa-systems/41402-powerful-speakers-outdoors-7.html#post2798049
oops, I should at least post a pix of the Spirits...
This is a pix of the "Spirits" with Altec 409 co-axials mounted. Subsequently Jordan JX92S drivers were installed, and that's how they are today. My audio partner, Mike has them and he's recently moved so no new pictures with the Jordans.
As I've stated before, cosmetically a knock-off, but conceptually not.
This is a pix of the "Spirits" with Altec 409 co-axials mounted. Subsequently Jordan JX92S drivers were installed, and that's how they are today. My audio partner, Mike has them and he's recently moved so no new pictures with the Jordans.
As I've stated before, cosmetically a knock-off, but conceptually not.
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I build all kinds of speakers horn, BR,TL,bookshelf,D'appolito but a OB in a room works best for bas. Because the back-wall reflection of the OB extends the sub-bas where the monopole the same reflection reflection kils the subbas because it has opposite phase.
Also the polar diagram for the sides is good to prevent reflections of the side walls.
Here pictures of my current 94dB kugelwellenOB-system -3dB 30-18000Hz. It isn't finished yet but then you can not see the woofers any more so I show them nude.
Also the polar diagram for the sides is good to prevent reflections of the side walls.
Here pictures of my current 94dB kugelwellenOB-system -3dB 30-18000Hz. It isn't finished yet but then you can not see the woofers any more so I show them nude.
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I build all kinds of speakers horn, BR,TL,bookshelf,D'appolito but a OB in a room works best for bas. Because the back-wall reflection of the OB extends the sub-bas where the monopole the same reflection reflection kils the subbas because it has opposite phase.
Also the polar diagram for the sides is good to prevent reflections of the side walls.
Here pictures of my current 94dB kugelwellenOB-system -3dB 30-18000Hz. It isn't finished yet but then you can not see the woofers any more so I show them nude.
Looking good
I do not know what he is talking about. Usually people worry about the out of phase wave from dipole not monopole. Even that is not a major concern in real rooms:
From Linkwitz lab's:
"Often concern is expressed over the fact that the rear radiation from a dipole is out of phase with the front radiation, and that thus any sound reflected from a wall behind the speaker would cancel sound coming from the front of the speaker. Cancellation can only occur when direct and reflected sounds are exactly of opposite phase (180 degrees) and of the same strength. Since direct and reflected sounds travel paths of different length, they undergo different amounts of phase shift. Thus, the phase and magnitude conditions for cancellation are given only at certain frequencies, if at all. At some other frequencies direct and reflected sounds will add. The same also applies to a monopole speaker in front of a wall. The only difference is in the frequencies for which addition and subtraction occur. The best remedy is to move the speaker away from the wall, or to make the wall as sound absorptive or diffusive as possible"
Due the wave length and path traveled the reflection will ad in opposite phase
In my case the baffle is 1.5mtr from back wall so average travel will be near 4mtr.
So this wil be in phase with the front of the OB when the traveled distance is 1/4 up to 1/2 wave length.
1/4 = 4X4=16mtr =>21Hz
1/2 = 2x4= 8mtr => 43Hz
This means in my case the reflected wave of the back wall will ad in phase from about 43Hz down to 21Hz. And will help to give good response down to 20Hz with -3dB at 30Hz.
That as why a OB is a great device. A mono pole would have the same effect only then it will kill most of the sub-bas what people can judge as tight bass, what I would call no bas.
At the sides of the openbaffle is no sound because it is shorted so it can not reflect on the side wall. With a monopole you would have these reflections play a large roll. In end effect a monopole would suffer more reflection problems in my listening room then a dipole.
A dipole will have a lot of reflections but a monopole also suffer all kinds of reflections, do not let confuse you. Due the longer wavelength at low frequencies the reflections are all over the place and the shape of your room and used material will dictate the end result.
Reflections between walls between floor and sealing and floor bounce this will create comb-filter effects and standing waves. The comb-filter effect is already introduced when you are playing stereo with two speakers.
So you can not get rid of these effects so I think you shout use them in your favour then a OB is very nice.
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...only for certain frequencies. The very same is true for a dipole. Now consider that we're talking about wavelengths that don't produce "reflections" because the room is small compared to the wavelength.