I am about to build my first diy sub. I will be building a sealed unit (mostly since that is what all the advice says I should do for a first project).
All the projects that I have seen have a side firing driver. I seem to remember hearing that having a downward firing driver was also possible. Is that right? What are the pros and cons?
I would like to have it firing down if possible, since that will provide maximum protection for the driver from accidental damage (Kids running about).
Any advice?
Thanks
James
All the projects that I have seen have a side firing driver. I seem to remember hearing that having a downward firing driver was also possible. Is that right? What are the pros and cons?
I would like to have it firing down if possible, since that will provide maximum protection for the driver from accidental damage (Kids running about).
Any advice?
Thanks
James
Most subs like to be faced sideways i think, generally when theyre faced down you can have problems with the distance it is off the floor etc. Also having it facing down will also eventually make the cone sag out of its natural position. The first sub i built is downward facing and its still going strong.
Hello,
There are plusses and minuses to both side/front firing and down firing.
Down firing pluses:
-Your cat or young child cannot easilly damage the cone of the driver or the grille.
-The driver will load off the floor giving your more output.
-aesthetics are not as important as you will not see the front baffle as it will be facing the floor.
Down firing minuses:
-may sound a bit boomier than a front firing because it is firing off the floor.
-the sound will change somewhat depending on floor covering material. Carpet, tile, wood etc.
Front firing pluses:
-you can tune the woofer & your room by loading the woofer off a wall, into a corner or letting it fire straight into the room.
Front firing minuses:
-can be damaged by pets/kids.
-you better make it look good because you will be looking at it.
As far as the cone sag goes, it does not happen. It is only the weight of the cone on the surround and spider. You would do more damage to your woofer by having your dog fart on it.
As long as your downfiring woofer is about 3 inches from the floor, you will have no problems.
Thanks
KevinLee
There are plusses and minuses to both side/front firing and down firing.
Down firing pluses:
-Your cat or young child cannot easilly damage the cone of the driver or the grille.
-The driver will load off the floor giving your more output.
-aesthetics are not as important as you will not see the front baffle as it will be facing the floor.
Down firing minuses:
-may sound a bit boomier than a front firing because it is firing off the floor.
-the sound will change somewhat depending on floor covering material. Carpet, tile, wood etc.
Front firing pluses:
-you can tune the woofer & your room by loading the woofer off a wall, into a corner or letting it fire straight into the room.
Front firing minuses:
-can be damaged by pets/kids.
-you better make it look good because you will be looking at it.
As far as the cone sag goes, it does not happen. It is only the weight of the cone on the surround and spider. You would do more damage to your woofer by having your dog fart on it.
As long as your downfiring woofer is about 3 inches from the floor, you will have no problems.
Thanks
KevinLee
jshammond,
It depends on whether the particular sub driver has been designed for down firing. All drivers can be side firing. Downfiring a sub driver that has a loose suspension can cause damage as it will be more likely to reach mechanical excursion limits than if it is mounted side firing.
Adire Audio has a good page explaining (mathematically) the amount of sag caused by gravity, and calculating using the specs of your driver, whether this will be a problem - see: http://www.adireaudio.com/tech_papers/driver_orientation.htm
If you do the math you find:
'If the sag is more than 5% If the sag is more than 5% of the Xmax of the driver, then it's not meant for horizontal (downfiring) mounting."
I prefer to side mount (I believe the driver will last longer).
Hope this helps,
David.
It depends on whether the particular sub driver has been designed for down firing. All drivers can be side firing. Downfiring a sub driver that has a loose suspension can cause damage as it will be more likely to reach mechanical excursion limits than if it is mounted side firing.
Adire Audio has a good page explaining (mathematically) the amount of sag caused by gravity, and calculating using the specs of your driver, whether this will be a problem - see: http://www.adireaudio.com/tech_papers/driver_orientation.htm
If you do the math you find:
'If the sag is more than 5% If the sag is more than 5% of the Xmax of the driver, then it's not meant for horizontal (downfiring) mounting."
I prefer to side mount (I believe the driver will last longer).
Hope this helps,
David.
Yeah, I saw your other thread after I saw this one. 
You know, when I was 17 (way too long ago) I took a cab my father already had, tried to duplicate it using scrap plywood in his worshop (3/4 inch at any rate, but with way too many voids) and then dropped a couple of Radio Shack 15" woofers, 8" midranges and horn tweeters into both boxes. Crossover was straight off the shelf as well. Damn I thought those things sounded good!
You're way ahead of me on the curve at that age. Of course, back then no one had too much other than RS. I'm not sure Speaker Builder magazine was even around at the time. Keep working at it (and drop a Shiva or Tempest in that box when you get a chance!)
You know, when I was 17 (way too long ago) I took a cab my father already had, tried to duplicate it using scrap plywood in his worshop (3/4 inch at any rate, but with way too many voids) and then dropped a couple of Radio Shack 15" woofers, 8" midranges and horn tweeters into both boxes. Crossover was straight off the shelf as well. Damn I thought those things sounded good!
You're way ahead of me on the curve at that age. Of course, back then no one had too much other than RS. I'm not sure Speaker Builder magazine was even around at the time.
Keep working at it (and drop a Shiva or Tempest in that box when you get a chance!)
well, folks, I'm 19, living at home, and I'm just building my first pair, and I have to say, they're horrid!
The 15"ers on them have very limited excursion, so low bass above 2 watts causes the woofers to bottom out (Waah!) and make this horrible banging noise... the tweeters are not bad, peizo, and the 2.5-way config I've got them in is actually fairly nice to listen to... it's a sealed box so the bass is 3dB quieter than I'd like, but with a little EQ it's just fine.
I want to sell the boxes as fast as I can once I get the finish put on them, so I can build some better ones.... already plans are in the works for a 3-way completely amped speaker pair (VERY ambitious) so all you need is wall current and a line-level signal...
anyway... I feel pretty good for being 19.
The 15"ers on them have very limited excursion, so low bass above 2 watts causes the woofers to bottom out (Waah!) and make this horrible banging noise... the tweeters are not bad, peizo, and the 2.5-way config I've got them in is actually fairly nice to listen to... it's a sealed box so the bass is 3dB quieter than I'd like, but with a little EQ it's just fine.
I want to sell the boxes as fast as I can once I get the finish put on them, so I can build some better ones.... already plans are in the works for a 3-way completely amped speaker pair (VERY ambitious) so all you need is wall current and a line-level signal...
anyway... I feel pretty good for being 19.
Really? Hmm...
At 1 watt, it gives quite a bit of excursion (~1/2") at the low frequencies without any unpleasant noises... when turned up much higher, there is a new sound accompanying kick drums that sounds, by my intuition, like the voice coil hitting the back plate. Guessing by where I see things, I think this is a real possibility...
anyway, I didn't mean to hijack the thread like that... please resume normal discussion.
I'd heard that by making a sub down-firing, it eliminated an unpleasant artifact of PA speakers where, if you're just the wrong distance away, the bass is really weak... this being undesirable, down-firing woofers were developed in order to reduce or eliminate the effect.
Anyone know about this?
At 1 watt, it gives quite a bit of excursion (~1/2") at the low frequencies without any unpleasant noises... when turned up much higher, there is a new sound accompanying kick drums that sounds, by my intuition, like the voice coil hitting the back plate. Guessing by where I see things, I think this is a real possibility...
anyway, I didn't mean to hijack the thread like that... please resume normal discussion.
I'd heard that by making a sub down-firing, it eliminated an unpleasant artifact of PA speakers where, if you're just the wrong distance away, the bass is really weak... this being undesirable, down-firing woofers were developed in order to reduce or eliminate the effect.
Anyone know about this?
Yeah. I just don't buy 1W for a whole half inch...sure you didn't mean half milimeter? 
Thread hijack my butt.. (oops ) this thread's had no strictly-on-topic posts since Dave Bullet. Besides, this refers to bass speakers, that's what the thread was originally about so it's not too far off
Tim
Thread hijack my butt..
(oops ) this thread's had no strictly-on-topic posts since Dave Bullet. Besides, this refers to bass speakers, that's what the thread was originally about so it's not too far off Tim
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