An OB with any kind of wings has perfect/symmetric dipole response only at rather low frequencies. So, it is more about edge diffractions in mid-tweeter range and yes left/right side response will be a little different.
Which side is better is impossible to say, it depends aslo on how backwards radiation is reflected. Most likely measured response at listening spot will be very much just the same.
mashaffer, do you have dimensions ruled out yet? What size drivers will be used? Please tell also distance to front- and sidewall.
Considering dipole summation, wings add the total width of the baffle. Above on-axis nulling frequency the egdes of the frontside flat panel make diffractions.
Often wings don't come up to mid/tweeter hight at all and the flat baffle can be get narrower upwards.
The Edge is a nice little program to study baffle diffractions. Here an example
Which side is better is impossible to say, it depends aslo on how backwards radiation is reflected. Most likely measured response at listening spot will be very much just the same.
mashaffer, do you have dimensions ruled out yet? What size drivers will be used? Please tell also distance to front- and sidewall.
Considering dipole summation, wings add the total width of the baffle. Above on-axis nulling frequency the egdes of the frontside flat panel make diffractions.
Often wings don't come up to mid/tweeter hight at all and the flat baffle can be get narrower upwards.
The Edge is a nice little program to study baffle diffractions. Here an example
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I thought diffraction occurs at lower than on-axis nulling frequencies. The sides of the baffle is strongly illuminated and hence strong diffraction.
Highs dont diffract since they are directional and hence dont hit the baffle edges, at least not strong enough
It is the wavelength vs. baffle dimensions thing. A long wave just smoothly bends around the edge. Alike, typical edge rounding has no effect for long waves. Directionality happens above the biggest wiggles in response, as you can see above 2kHz in my Edge simulation. On-axis nulling at 600Hz, left-right asymmetry in diffractions 300-1500Hz.
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Sorry that I didn't give you more info. I have these OB speakers that I built some time ago and they really sound better than they ought to considering my ham-fisted craftsmanship. They have good usable output down to about 40Hz. Bass guitar and double bass sound as they should but the side plates are only about 4" deep. The top cap would allow me to extend them (plexiglass) about another 4" so I though of trying it to see if it gave me any more extension or just a tick more output at 40Hz. At the same time I have read that equal length sides can lead to resonance problems as you make them larger.
FR is a MA CHR-70 and the helper woofer is a Goldwood OEM 10".
FR is a MA CHR-70 and the helper woofer is a Goldwood OEM 10".
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Resonance is a large part of how these cabinets function so, just what is a problem or not.
There is a bit of resonance possible with wings perpendicular to the baffle, though 4" relative to LF wave lengths is maybe trivial. I'm baffled by the insistence on zero damping material on those wings, not to mention the rarity of departing from 90 degrees. Once again I need to build it and see (hear/measure) for myself.
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