Does anyone have any actual proof on what the difference it when the sub is downfired rather that flush mounted? More specific, what happens to the bass and the clairity when the sub is downfired?

Thanks,
-Kevin

 

Go here..... Read.... Learn

www.installer.com/tech/aiming.html

AJ

 

Thanks, That was interesting info, but it really didn't help. That page was talking about in a car with a trunk aim the whole box either forwards or backwards. I want to know is up or down, while keeping the box the same, in a hatchback car.

 

Just have it firing up.....

 

If you would read the THEORY, and not the actual application, it would help you a lot.

Basically the guy's saying that the best way to fire the sub IN ANY CAR is toward the rear. Ask Jim85IROC. He's put a few (from what he's said and shown) facing the rear of the car and he says it worked very well (in the well ).

I can't see how it would make a huge difference in our cars wether it was facing up or toward the rear just because even facing up, there's not a lot of room from the speaker to the rear of the car for any "out of phase" sound waves to develop.

Although I have to say that facing them DOWN would be a real chore. You'd have to leave room (a gap) for the sound waves to get out of the well. That would only further limit the size of box which you could use. Plus I can tell you that I've tried it. I had a small truck style box with one 8" in it. I tried all different positions and the only one that sounded good was facing the rear. It may have sounded good facing up, if the well was covered somehow to keep any out of phase shift from developing.

I hope this helps more. Good luck.

AJ

 

I don't think you know what downfiring a sub means. Attached is a picture of normal flush mount(facing UP, not forwards or backwards) in my custom box. If I leave the box in place and hook up the sub facing DOWN (not forwards or backwords), that is called downfiring. I did read the theory also, and it does make sense to me, but does not apply to my specific question. I appreciate you trying to answer my question.

 

No. That's called inverting a sub.... I have a downfiring sub in my house. It fires toward the floor. That's why they call it a "downfiring" sub.

The only advantage to doing that would be increasing the interior volume of the sub enclosure. I don't think it'll sound any better or worse. IMO it may not be as loud, or as accurate simply because you are covering the side of the cone which is firing into the listening area with the basket itself. Just my 2cents.

I don't know. How about trying it. That's the only real way to tell.

AJ

 

Downfiring a sub increases db's by approx 3, but decreases clarity. Upfiring looks better and sounds ALOT better.

 

But if you REALLY want your sub to pound, face it towards the back of the car (in the well). It works really good, makes it a little bit more of a steath system, and I think it sounds better than with it facing up.

 

Do you mean his version of downfiring, or mine? :sillylol:

Seriously, the only things that are gonna give you a 3 dB increase are

1.Double the power going to the subs

2.Sometimes a ported enclosure, but only if it's designed right, and even then it'll only be a 3 dB increase at a certain frequency

3.Double the amount of subs you have.

4.Changing to a sub that has a higher sensativity level (IE spl@1w/1m).

That's it.

AJ

 

Jim85IROC knows alot about this stuff......you might try to PM him....

 

Downfiring isn't going to give you a 3db gain....as said above the only theoretical way to do that is double the power going to the subs (assuming you have more 'throw' left in the sub) or double the cone area.

 

Next time you get a db meter, put two 10's facing up in the well, the down fire and see what happens.

 

Next time you're at the drag strip, turn your engine upside down and see if you shave .3 seconds off your ET, OK?

Or better yet, go down the strip in reverse with the engine upside down!! That should shave off at least .6 seconds then, right?

Then after that bolt your wheels on so they're sticking out the fenders....



AJ

 

Here's a discussion on another message board about what "Downfiring" a sub is, how to do it, and what advantages it has.

»»» • «««

Just click on the dot above and you'll get the "POINT"!!!

AJ

 

It is a proven fact that facing a sub toward a wall creates extra decibles, it is also said that below 80 hz, ai thinks it's 80, that bass is non- directional, that is correct for home theatre but not for car audio. It is also a proven fact that the longer that it takes the bass wave to reach the front cabin, the better the SOUND QUALITY IS.

However, firing your subs upward almost has the same effect as facing them downward although the soundwaves will be a bit loneger if you downfire them.

There are other ways to get more db's without downfiring. It's called compression loading. This is where you build a box that has another wall of wood in front of the subs. the subs must be angled though or else the waves will bounce back off of the wood and cancel and you'll have crap. You have to have at least a 20 degree angle to make this work, and let me tell you, it works. If this still sounds weird picture this:

A box 3 feet wide and 1 foot tall. 3 pieces of wood, the one in the middle os angled upward and has the subs on it. So ther is an opening 3 feet by approx 4 or 5 inches with the subs resting in there.


I have the loudest camaro I have ever heard and My box is angled so that the subs face the hatch window but are also angled to lenghten the soundwaves and the the other bix boounces right off the glass.

Here's what I got:

2 Kicker Solo Baric 12's ( old style with the 'K' on them)
2 Rockford Punch 10's
Rockford amp for the 12's and an Alpine amp for the 10's

Boston acoustics highs, Pioneer head unit and a clarion EQ Hig output ALT. and a 1.5 farad cap

Don't bash me for saying I have the loudest camaro ever or something, This car is in Hawaii and thus far I have not heard a camaro that comes close.

 

If you down fire a sub, and there is the same distance between the all four corners of the box and the floor, you will get less db's beceause the waves will cancel each other out. Also carpet absorbs sound waves. That is why compression loading works best, the wood makes the soundwaves even stronger.

 

Actually, a sub mounted in a box, whether it be basket first, or cone down, the airspace is the same. It has to compress, or use the air volume in the box. Just come facing is the biggest difference. Bass is non-directional, but for max output, woofer placement is a science. some cars you can be louder by facing towards the trunk lights, or some towards the seat. (trunk cars)
But for these cars, you can fire the subs up, or at an angle towards the glass for most output IMHO.
By facing a sub down, in no way, shape or form will ever gain you 3 dbs.....

 

I was talking about the volume of area that the basket consumes. If you invert a sub, the space that the basket was taking up, will now be added to the internal volume of the enclosure.

For instance....The average 12" woofer takes up .12-.15ft³ of space in the box. If you build a box that has 1.5ft³ and put the woofer in the box like usual (using a .15ft³ woofer), you now have a box that's 1.35 ft³. If you mount it so it's firing into the box, and mount it so it's sitting outside the box, you are now back to 1.5ft³ of internal volume.

This may not seem like a big deal, but some 12" subs are made for a 1ft³ sealed enclosure (or sometimes smaller), and you're usually allowed ±10% before it'll really start to change the SQ. But .15ft³ is 15% of 1ft³. That's enough to change the characteristics of the woofer, whether it be SQ or SPL.

That's all I was trying to point out. Removing the woofer from inside the box 'may' give you the extra space you need because you had to build the box smaller due to a confined trunk/hatch.

AJ

 

BTW, What did you mean to type there?

That sounds a little too pornographic for me to understand what you were really trying to say.

AJ

 

One more thing. The reason I posted that link was to show 5.0L1992RS that he was using the wrong term for inverting a sub (aka reverse firing). He was calling it "Downfiring". I was trying to explain what Downfiring actually IS, and he seemed to think that I was a moron.

You've got to now the lingo otherwise people are going to misunderstand your questions. Kinda like I did.

AJ

 

Sorry, typo...meant to say 'cone' facing....