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Chrono
03-03-2004, 02:34 PM
Is there any benefit in having a down firing sub vs. a front firing sub?

Thanks

Sir Terrence the Terrible
03-03-2004, 02:46 PM
Is there any benefit in having a down firing sub vs. a front firing sub?

Thanks

I am not aware of any. Doc Greene, oh Doc Greene......I know you are out there dang it!!!

spacedeckman
03-03-2004, 06:02 PM
a downfiring woofer would be a little less sensitive to a crossover slope that was too shallow. But just a little.

Out and out performance, nothing that I can think of.

r3Wind
03-03-2004, 08:31 PM
Audio wise I'm not so sure, but I would imagine that a downfiring sub would be a little better at getting the floor rumbling during explosions :cool:

markw
03-04-2004, 03:50 AM
Audio wise I'm not so sure, but I would imagine that a downfiring sub would be a little better at getting the floor rumbling during explosions :cool:

.. .and would do a better job of pissing off the downstairs neighbors. :)

wasch_24
03-04-2004, 05:22 AM
I don't think that there is any affect on sound output. Think of this though, over time the whole diameter of the woofer is helping to support the weight of the sub in a down firing woofer as opposed to the top and bottom edges in a side firing model.


Is there any benefit in having a down firing sub vs. a front firing sub?

Thanks

nightflier
03-04-2004, 09:41 AM
...over time the whole diameter of the woofer is helping to support the weight of the sub in a down firing woofer as opposed to the top and bottom edges in a side firing model.

...Not to mention the sides having to support the driver. Some sub drivers are 15" wide or more and weight substantially more than standard speaker drivers so this could definitely be a factor. I didn't consider this when I purchased my sub and it's an interesting point. Since the driver typically will move substantially more during use than a typical speaker driver, I can imagine that a fragile material like rubber-coated paper would eventually develop folds or tears and distort the sound. Based on this, a down-firing sub would probably last longer.

Another important factor when considering whether to purchase a down-firing sub, is what your floor is made of. Most down-firing subs don't include a base-plate so putting such a sub on lush carpet, even with spikes, would produce a significant amount of damping. If that is your situation, you may want to make sure you purchase one with a base-plate. Of course, the sound waves would still be affected once they pass the base-plate, but I imagine this would be the same situation with a side-finring sub. Then again, much of this is dependent on how directional the driver is and as freqncies reach lower Hz. , the directionality of the soundwaves is less discernable.

So, to make a long story short, I think the primary factor is the quality of the driver. A company that takes great care to select the most solid and reliable drivers will produce a much better sub. This would also imply that a side-firing driver should be made differently than a down-firing one because of the wear & tear factor. When you shop around, be sure to find out as much as you can about the drivers.

Richard Greene
03-04-2004, 11:51 AM
I think it's very important that with all other speakers tiurned off, you cannot hear male voices from your subwoofer. That means little output above 80Hz. which makes a subwoofer much more likely to be sonically invisible which it should be.
(Don't test with deep bass voices such as Barry White)
A subwoofer is meant to extend the frequency response of your other speakers without acting as a separate sound source -- it should not be noticed until you shut it off.

You know the subwoofer-satellite speaker is good when friends say things such as:

"I never heard such small speakers produce such deep bass."

and then you say to men:
(1) "That 48" by 18" tube is my DIY subwoofer"

to which he'll respond:
(2) "Oh I thought that was a bass trap"
.
.
or to women:
(1) "Those small speakers have built-in activated servo-deregulators and
teflon dielectrics -- they're NOT ordinary speakers like most people have."

to which she'll respond:
(2) "You're so knowledgable about electrical things ... are you single?"



If you use a crossover that allows the lowest frequencies (over 80Hz.) of male voices to be heard from the subwoofer (not a good idea) then a downfiring driver aimed at thick carpet and padding (or 4" Sonex sound absorbers) will mechanically filter a little of the upper bass.

A downfiring driver will make a floor rattle louder than a near-the ground front-firing driver will (for those floors, mainly plywood, that rattle). Of couse some surround sound videophiles like vibrating floors, but two-channel audiophiles don't.

You can mechanically filter even more upper bass over 80Hz. by facing a driver away from your ears, but not if doing so will fire the driver directly into a wall behind the subwoofer(which may rattle).

A driver's cone will sag 0.5 to 1.0mm from gravity when downfiring unless specifically designed to be downfiring (cone mounted off the center of the stroke as a gravity offset)
but will subwoofer manufacturers pay driver manufacturers extra for that custom
design so you don't lose 5% to 10% of your displacement due to cone sag?

After many years the downfiring cone will sag a little more than when it was new.