Subwoofer Placement (1 Viewer)

[richard_v]

Is one large sub better than 2 smaller ones placed at opposite ends of a room? If 2 subs are perferred, is a front / back or side to side arrangement better.

Rich

 

[Jason Monette]

It is my understanding that it is better to corner load the subs to prevent a dead spot. If i am wrong, I am sure someone will let me know.

To answer your question. It depends on the sub.

 

[Neil Joseph]

This question is impossible to answer fully because of rooms all being different from each other. A front & rear plaement can work but it becomes more diffiicult exponentially as far as finding the correct/right placement to avoid nulls and peaks. I would personally prefer a single larger sub over 2 smaller subs not only for this reason, but for the fact that it can extend lower and not just play louder.

 

[Terry Montlick]

Hi Rich,

According to some recent research at Harman: two subs, placed at the center of the front and rear walls, are better than one placed anywhere. However two smaller subs do not necessarily equal one larger sub in audio power. It's probably better to have two large subs, because they will cancel each other at certain frequencies, making the response smoother, but reducing efficiency.

Regards,
Terry

 

[Wayne A. Pflughaupt]

According to some recent research at Harman: two subs, placed at the center of the front and rear walls, are better than one placed anywhere.

Not this one again! Am I the only one that noticed that the tests were performed in a nearly-square room? Or the disclaimer at the top of the piece that notes that the conclusions reached are only valid in a similar room??

Regards,
Wayne A. Pflughaupt

 

[Terry Montlick]

Hello Wayne,

Or the disclaimer at the top of the piece that notes that the conclusions reached are only valid in a similar room??

I read both the original AES paper and the abbreviated on-line white paper. Perhaps I missed it, but I didn't notice such a disclaimer.

Regards,
Terry

 

[Jason Monette]

Play nice kids

 

[Wayne A. Pflughaupt]

I read both the original AES paper and the abbreviated on-line white paper. Perhaps I missed it, but I didn't notice such a disclaimer.

In the latter: page two, paragraph five. Not that it was a necessary statement – it should go without saying that any study on sub placement that does not include a myriad of rooms with different sizes, layouts and furnishings is only valid in the room it was performed in – or one identical to it.

Another aspect of the study I have a problem with is that one of the primary objectives in finding optimal sub placement was to achieve the best response over the widest area – in this case for 16 viewers. Obviously this experiment was intended for people with large, dedicated custom installations. I think it’s safe to say only the smallest minority of HT enthusiasts entertain that many guests at one time - or have the space to.

Bottom line, studies like this should be taken with a grain of salt and should not replace rigorous experimentation, evaluation and measurement in one’s own room.

Regards,
Wayne A. Pflughaupt

 

[Terry Montlick]

Hi Wayne,

My comments are strictly on a friendly basis, and I don't mean for them to be argumentative for their own sake. I only want to get at the truth, and to make sure that people in this forum get the best available information.

Just a correction on your interpretation of the citation. It reads:

"To test the effect of differing room dimensions, configurations 1-20 on pages 53-55 were duplicated (to scale) in five differently dimensioned rooms. For clarity, only Std and LF factor are shown. Given the widely varying dimensions, the results are surprisingly consistent."

So the conclusions are not limited just to this room, but to other rooms of very different dimensions.

Here's something that I agree with you on.

You are right in pointing out that this study was to find the best overall response over a reasonably broad area: a six by six-foot square. Of course, 16 test positions does not imply 16 viewers (I think you'd have trouble packing them in on 1 1/2-foot centers!): only the possibility that a viewer might be within any part of the test area. If you are alone in your HT always sitting in the same viewing position, then you can optimize subwoofer placement for this position only, and this research is irrelevant.

And I also agree with you that measurement in individual home theaters is absolutely necessary. But to the extent that studies like this one can give general guidelines based on solid, systematic experimentation, I think they are valuable.

Regards,
Terry

 

[Wayne A. Pflughaupt]

Hi Terry,

Of course, 16 test positions does not imply 16 viewers (I think you'd have trouble packing them in on 1 1/2-foot centers!

Well, I certainly blew that one, didn’t I? Color me embarrassed! :b

Regards,
Wayne A. Pflughaupt

 

[Terry Montlick]

Hi Wayne,

Your point about widely varying room sizes is a good one. I checked the original AES paper, and Welti does not give the sizes of the other rooms he simulated - only the room ratios.

My assumption is that they were roughly the same volume as the original room. I too would expect the his results would not apply for much larger rooms. I assume he is still talking about home theater-sized spaces.

But since these are assumptions, I think I'll drop Todd an email to find out what dimensions he actually modeled. I'll report my findings on this thread.

I think we're finally on the same "wavelength", Wayne. Overall, a very productive discussion, I think.

Regards,
Terry

 

[Terry Montlick]

Wayne (and others who might be following this thread),

I just heard back from Todd Welti on the subject of the various room dimensions he used. My assumption was correct. He kept the room volume fixed, while varying the room ratios. So his results are relevant for rooms of comparable size but different dimensions.

Regards,
Terry