Sub placement - A different perspective

[Topend]

We all strife to position our subs to get the flattest FR possible in our room.

What if the goal was to overcome a limitation of the sub and not worry so much about peaks (that can be tamed with EQ) elsewhere. For example if my sub starts to roll off below 22hz, could I find a location in my room that would boost the 15-20hz range.

I have not experimented with this in mind but it is generally accepted that a corner will boost the sub effect, but at what frequency. Is it predominantly 50hz. I don't know but next time I have some time at home alone I might do some testing.

Any input from those that know would be appreciated.

Dave.

[NorthStar]

Dave, can't go lower than what your sub is capable of to start off with.

[DYohn]

Dave, the answer to your question is yes. Using room gain you can position a sub to emphasize certain frequencies, depending on the shape and size of your room. Those can be below the -3db rated extension of your sub, although that is difficult to achieve. Rives Audio has a good room simulator that can help you determine what frequencies you could most likely enhance through placement. In most rooms, corner placement will enhance frequencies from about 50Hz up.

Bob, you can indeed use room gain to emphasize frequencies below 20Hz. A subwoofer's rating is its -3db point, and much like a properly tuned enclosure can extend FR below fs, room gain can create higher SPL at very low frequency using information that is below the -3db point of the system.

[Topend]

Dec 31, 2011 16:39:10 GMT -5 NorthStar said:

Dave, can't go lower than what your sub is capable of to start off with.

G'day Bob,

It is more of a general discussion more so than aimed at my particular sub. Having said that if I can identify something that would be a benefit in my system I would give it a try.

Cheers,
Dave.

[Topend]

Dec 31, 2011 17:36:22 GMT -5 DYohn said:

Dave, the answer to your question is yes. Using room gain you can position a sub to emphasize certain frequencies, depending on the shape and size of your room. Those can be below the -3db rated extension of your sub, although that is difficult to achieve. Rives Audio has a good room simulator that can help you determine what frequencies you could most likely enhance through placement. In most rooms, corner placement will enhance frequencies from about 50Hz up.

Bob, you can indeed use room gain to emphasize f's below 20Hz. A subwoofer's rating is its -3db point, and much like a properly tuned enclosure can extend FR below fs, room gain can create higher SPL at very low frequency information that is not withint the -3bd point of the system.

Great info, thanks.

I will look at Rives Audio.

Dave.

[NorthStar]

Gotcha David; more room gain (emphasis) into some specific regions.

* Not without some limitations within the capabilities of the subwoofer(s) itself though.
Like stress, distortion, overridding, commotion, etc.

[Topend]

Dec 31, 2011 17:49:56 GMT -5 NorthStar said:

Gotcha David; more room gain (emphasis) into some specific regions.

* With some limitations within the capabilities of the subwoofer(s) itsef though. Like stress, distortion, overridding, etc.

Boominess come to mind too.

Dave.

[NorthStar]

...And within the capability of the sub amplifier as well.

[xki]

Dec 31, 2011 18:23:47 GMT -5 NorthStar said:

...And within the capability of the sub amplifier as well.

I've run a few sweeps from time to time that start at 1Hz and slowly go through 250 or so. Even though my subs are rated at ~22-25Hz, the cone on the driver is moving a lot of air all the way from 1. If there some way to have a room amplify the frequencies below the rating of the sub box, it would be great. My room cannot!

[NorthStar]

Laws of physics and fusions. ...Mass, Space Travel, Air, Displacement, and Speed.

[DYohn]

xki, if the cone is moving the sound is there. But low frequency below starting somewhere between 18 and 24Hz cannot be heard by humans...

[NorthStar]

Like a real earthquake, right David?