Jump to content
The Klipsch Audio Community
AHall

1802 sub port experiment

Recommended Posts

6 minutes ago, Chris A said:

What is the longest dimension of your listening room?  This will determine the transition to "pressure zone" region or band.  In my room, that transition happens at ~14 Hz...calculated using:

 

     1132 ft/sec / (2*39.5 feet))--a half wavelength calculation. 

 

Above this frequency band, you've got the "sparse mode region" of the room (usually up to 100-300 Hz, depending on room volume and reverberation time), and above that, the "dense mode region".  At the commercial cinema scale, there is no real "transition to pressure zone" due to the room's dimensions since they are quite large by comparison to home hi-fi sized rooms.

 

Chris

My Room is 19'6" L  x 14' W x 9'H

Share this post


Link to post
Share on other sites

Then that's about a 29 Hz transition frequency. 

 

Of course, I can't tell you what happens in terms of measured frequency response of subwoofers at that frequency, but I can tell you that below that frequency, bass response no longer behaves like waves sweeping across the room, rather it's more like living inside a drum (or the interior of an automobile).  Anything that "hits the drum head" below that frequency will more or less instantly pressurize the entire room.

 

From a source, the effect of the pressure zone in terms of "cabin gain":

 

Quote

Once this magic frequency is reached [i.e., the transition to pressure zone], bass output will increase by about 12 dB/octave below that frequency [relative to full or half space response].

 

Chris

Share this post


Link to post
Share on other sites

You don't really need fancy equipment for proper measurement. A hole, microphone and an open field works just fine.

 

If you really need a full space measurement hoist it up on a crane.

Share this post


Link to post
Share on other sites
50 minutes ago, glens said:

A crane's not fancy equipment?

 

:)

 

I guess you could rent a fancy crane. :unsure:

 

The post has been removed for some reason anyways.

 

What really matters is response in your room.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...