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Donald
03-06-2014, 05:31 AM
I understand that the low end is somewhat omni-directional but various photos have me confused.

Where should the port be located? Top, bottom or side?

This JBL doc shows it bottom and side.
http://www.lansingheritage.org/html/jbl/specs/home-speakers/1983-b380-b460.htm

I am retired. Am I starting to worry about stuff that does not matter? :blink: Hey, you kids, get off my lawn!

rusty jefferson
03-06-2014, 05:59 AM
I understand that the low end is somewhat omni-directional but various photos have me confused.

Where should the port be located? Top, bottom or side?

This JBL doc shows it bottom and side.
http://www.lansingheritage.org/html/jbl/specs/home-speakers/1983-b380-b460.htm

I am retired. Am I starting to worry about stuff that does not matter? :blink: Hey, you kids, get off my lawn!

I believe the manual that comes with the BX-63(A) mentions orientation isn't critical, however you may hear differences of boundary reinforcement with the woofer closer/farther from the floor.

rusty jefferson
03-06-2014, 06:31 AM
I believe the manual that comes with the BX-63(A) mentions orientation isn't critical, however you may hear differences of boundary reinforcement with the woofer closer/farther from the floor.


Robh3606 scanned the manual for the BX-63A into this thread, in case you don't have it.

http://www.audioheritage.org/vbulletin/showthread.php?32401-BX63A-Definitive-Answers-Needed

relyen
03-06-2014, 07:00 AM
I have a pair of B380s and spent many hours flipping them around trying to answer that question. Oh my aching back! :crying: My room that is carpeted over a crawl space and I found having the port closer to floor using the JBL supplied base yielded slightly tighter bass response. Using that orientation also worked well as it occupied less floor space.

Donald
03-06-2014, 07:11 AM
The seller also supplied a low platform that raises the cabinet less than 2 inches. Not sure of the sonic differences. Using the board gives me 4 dimples in the carpet. Not using it gets me a large rectangle. :)

rusty jefferson
03-06-2014, 07:55 AM
I've shared this image, and philosophy previously, so please excuse my redundancy. I feel this isolation/mounting makes a tremendous difference with my subs. It gets the woofers about 8" higher off the floor, reducing the boundary reinforcement, and the coupling/decoupling of the cabinets from the floor makes the bass more articulate by reducing energy lost into the floor.

You could experiment with elevating your sub(s) off the floor with perhaps blocks of wood to see if you hear any difference. You are retired now. ;)

gasfan
03-06-2014, 09:41 AM
Change that wooden plinth to a concrete one and you'll be pleasantly surprised.:)

But lose the spikes between the speaker and plinth with only 3 under it.

Robh3606
03-06-2014, 06:59 PM
In the frequency range and port tuning 26Hz it just doesn't matter. The wavelenghts are so long in comparison to the distance between the driver and ports you can put them where ever you want them. When I built my B380's they went on the side of the enclosure.

Rob:)

hjames
03-06-2014, 07:07 PM
In the frequency range and port tuning 26Hz it just doesn't matter.
The wavelengths are so long in comparison to the distance between the driver and ports you can put them
where ever you want them. When I built my B380's they went on the side of the enclosure.

Rob:)

Agreed - I ran my B380 on its side and now I run the 4641 on its side.
Plays well - no complaints.

relyen
03-07-2014, 06:32 AM
Must be the reason I spent many hours trying to convince myself I could hear a difference between orientations. :banghead: