what is happening?
when i use the room simulator and set up a perfectly symmetric left and right subwoofer to listener and room layout i get different frequency responses from the left and right subwoofer, why is that?
in a perfectly symmetric layout i expect to have identicle responses from the left and the right subwoofer.
when i use the room simulator and set up a perfectly symmetric left and right subwoofer to listener and room layout i get different frequency responses from the left and right subwoofer, why is that?
in a perfectly symmetric layout i expect to have identicle responses from the left and the right subwoofer.
Member
Joined 2003
An offset doorway or any windows, heater vents, etc., can muck up any LF 'symmetry' and why I've always had to tune each speaker individually for any 'symmetrical' layout, especially corners; and for true subs, even room construction variables such as what's on the other side of each wall can make a huge difference to the point where one vented sub is under damped and the other over damped to the point of being ~aperiodic and from dim memory in at least one layout the vent was sealed off! 🙁
here are some examples:
1st pic system response in phase
2nd pic system response out of phase
3rd pic left sub response
4th pic right sub response
the out of phase system response should not have those peaks
and left and right subs should have identicle freq responses and not have those differencies
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Member
Joined 2003
Check driver ans listener locations. Driver placement is not perfectly symmetrical or listener is not perfectly in the middle.
Here, I have reproduced for you. With perfect symmetry the result is as you should expect.
thank you, you got a much better result then i, but look close at the differencies in freq responses still present at 33hz, what is that?
Member
Joined 2003
You have not placed the subs symmetrically and the listening position is not centred across the width. If you scroll down there is a panel below the Speaker controls that shows the positions of the sources, or move the mouse over them.
thank you, but when i place the subs and listening position perfectly symmetrically within the room then the path length differs from the subs to the listening position, just what planet10 showed above
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Something is off, if the head was centred the dimensions would be drawn relative to the opposite corners. Could try re-entering the room dimensions in case one has somehow become fractionally misaligned from its 1 cm increments, though I can't think of a way for that to happen.
something have changed, with a new version the responses looks more to what could be expected, with gain set to 0db all looks fine but with a tiny timing difference, with 18db gain the out of phase peaks is coming back up, so there is still a slight difference in response between sub 1 and 2
