[Doc99]

I am considering a REL Q108 for a music system, but I am not sure about a downfiring sub in a second floor room. Would a frontfiring sub be a better choice for an upstairs room.I am concerned about the sound traveling downstairs. I know people say that the lower frequency is non-directional, but it seems to me that a downfiring sub must put more energy down to the ground then a frontfiring design. Just wondered if anyone has compared the 2 in an upstairs room, and noticed a difference.

 

[jpmst3]



Quote:
Originally Posted by Doc99 /forum/post/0


I am considering a REL Q108 for a music system, but I am not sure about a downfiring sub in a second floor room. Would a frontfiring sub be a better choice for an upstairs room.I am concerned about the sound traveling downstairs. I know people say that the lower frequency is non-directional, but it seems to me that a downfiring sub must put more energy down to the ground then a frontfiring design. Just wondered if anyone has compared the 2 in an upstairs room, and noticed a difference.

The sound will travel roughly same regardless of which direction (including downward) the sub is facing. The waves will be transferred via all connected air and solid objects, as in sub/the source to air to floor to sub-floor to joists to plaster/drywall back to air to ear. It won't make much difference how you slice it. You can prevent some of the direct vibrations from the cabinet (if there are any significant ones) by placing the sub on a pad or some other isolation device. Other than that the sound will radiate outward...

 

[TheEAR]

Agreed with what was posted above. Front,rear,up or downfiring will case as much complaints from those around you who are irritable.

 

[Doc99]

I guess in a way, I assume It is like when you point a speaker, the sound will always be loudest in the direction the speaker is facing. I think how the driver is facing right down at the floor, that it must be putting more sound and energy at the floor then a driver facing out into the room. I guess not!

 

[jpmst3]



Quote:
Originally Posted by Doc99 /forum/post/0


I guess in a way, I assume It is like when you point a speaker, the sound will always be loudest in the direction the speaker is facing. I think how the driver is facing right down at the floor, that it must be putting more sound and energy at the floor then a driver facing out into the room. I guess not!

That is mostly true for higher frequencies. However, lower freqs are mostly non-directional and simply radiate out in all directions. The best analogy I can think of is car stereos. You can hear a "booming" vehicle often from several hundred yards away but it can be difficult to identify which car is producing the bass. That is unless everything else on the outside of the vehicle is rattling. Notice, unless the windows are down you do not hear the upper freq range....

 

[JBLsound4645]

I have two sub bass units in operation. Eltax A 12-R 12 (downward firing) this is only used for sub bass extension of the three-screen and surround channels.


For forward firing I use the JBL 4645 18 THX professional for the exclusive LFE.1 track.


Both perform together nicely and it is very difficult to tell which is doing what, unless I switch the balance level over to left or right on the mixer consul. A film like Miami Vice uses mostly sub bass extension and hardly any LFE.1!

Also you hath to thinking 3-dimensionally just place the sub on its side so that the driver is facing outwards into the room!