Two possible problems from putting the sub near the window:
1. Bass will escape through the window, never to return.
2. The sub could vibrate the window and turn it into a large resonator (giving you a peak at the resonant frequency).
The first problem can never be cured.
With the second problem, this can be solved by increasing the mass of the window (thus lowering the resonant frequency to something lower than what your sub can do). I have no idea about those MarigoAudio tuning dots, but I would be skeptical if they had enough mass to treat a window.
You could increase the mass of your window by leaning something really heavy against it. Pad the corner of this object with some cloth/carpet and you're done.
Best solution is not to put the sub next to the window at all.
1. Bass will escape through the window, never to return.
2. The sub could vibrate the window and turn it into a large resonator (giving you a peak at the resonant frequency).
The first problem can never be cured.
With the second problem, this can be solved by increasing the mass of the window (thus lowering the resonant frequency to something lower than what your sub can do). I have no idea about those MarigoAudio tuning dots, but I would be skeptical if they had enough mass to treat a window.
You could increase the mass of your window by leaning something really heavy against it. Pad the corner of this object with some cloth/carpet and you're done.
Best solution is not to put the sub next to the window at all.