I certainly agree with that, based on my experience with dual 15” OB’s. I am thinking the drivers need to be bolted together face to face in a SLOB configuration with baffle openings slightly larger than driver OD, 1mm gap filled with felt. Otherwise that Cosmic Hippo makes the entire assembly shake like madness.
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Thank you Peter.
Might you have a picture of your setup, so to make sure I'm understanding correctly?
What's the frequency range you play your 15" SLOB?
I have not done it yet, but I will be...intent is to have the two 15” drivers in what amounts to a ripole configuration with the front slot being at the bottom of a live edge board. I think a pair of woofers bolted together with standoffs can be suspended inside a ripole enclosure so that vibration is minimized, and to the degree it does occur, the vibration is orthogonal to the front baffle.
I await some ordered hardware from Amazon to get going on it.
There are other ways to do it as well...I believe the key is to separate the function of driver mounting from the function of baffle wave guiding.
I have already magnet mounted my fullrange driver, so it can “poke through” a baffle hole instead of being directly mounted to it.
Once I achieve some of this I will post the pix.
I await some ordered hardware from Amazon to get going on it.
There are other ways to do it as well...I believe the key is to separate the function of driver mounting from the function of baffle wave guiding.
I have already magnet mounted my fullrange driver, so it can “poke through” a baffle hole instead of being directly mounted to it.
Once I achieve some of this I will post the pix.
The difference is often in the details.
I said to suspend with "bungee cord",
your example uses a hard cable, it is not the same.
Bungee cord when sized correctly absorbs vibrations.
“I remember it said that if the driver itself were solidly anchored ,
and the baffle supported by the driver ....
Then a very light baffle would suffice ..”
I intend to have the baffles independently supported from every driver.
Note that in retaliation to worry about baffle vibrations, users often try to make them more weighty, thicker etc...when all that does is move the resonance to a lower frequency where it becomes more likely to resonate! It is perhaps true, therefore, that bass baffles should be as light as possible, and midrange/tweeter baffles as heavy as possible? Exactly the opposite of many folks’ intuition.
and the baffle supported by the driver ....
Then a very light baffle would suffice ..”
I intend to have the baffles independently supported from every driver.
Note that in retaliation to worry about baffle vibrations, users often try to make them more weighty, thicker etc...when all that does is move the resonance to a lower frequency where it becomes more likely to resonate! It is perhaps true, therefore, that bass baffles should be as light as possible, and midrange/tweeter baffles as heavy as possible? Exactly the opposite of many folks’ intuition.
Indeed, that is one approach. A rigid connection from magnet to ground to mitigate the motion of the woofer, and a light baffle coupled to the driver frame. It's not so different from the swing in that it also holds the driver by the magnet and could use a light non-resonant baffle attached to the driver frame, but instead of a rigid connection to ground there is the swing allowing for free action-reaction.
I guess that's another thing for me to experiment. Bungee cord would absorb vertical vibrations from the floor/ceiling, which at first sight would seem an order of magnitude smaller that those from the driver frame/panel if held from the panel, or from the magnet/structure holding it. The swing would address the forward/backward vibration. But experimentation would tell.
FWIW, right now I use thin synthetic rope which is not stiff as steel so might be stretching some.
