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Main => Driving & Racing Cabinets => Topic started by: Howard_Casto on April 16, 2016, 08:38:55 pm

Title: Question about modifying a sub-woofer.
Post by: Howard_Casto on April 16, 2016, 08:38:55 pm
Ok so I picked up a 2.1 audio system for my rig.  It was marked down to 20 bucks because it was missing a cable or something stupid like that.  Anyway the sound is great, but the only problem is the sub woofer is too big.  It's one of those popular with pcs that has the little feet on the bottom.  It's a couple of inches too tall, not counting the feet. 

This isn't a super high end set or anything so the question is, how much is it going to alter the sound if I modify it?  The controls are in the sub as well, which is super annoying.  I'm going to take them out and mount them somewhere more convenient. 
Title: Re: Question about modifying a sub-woofer.
Post by: BadMouth on April 17, 2016, 10:40:10 am
Calculate the internal air space of the sub enclosure in cubic inches.
Make a new sub enclosure with different proportions, but the same amount of internal air space.
Reuse the air port out of the original.
Except for very narrow (like the speaker magnet is almost touching the back) enclosures, it should sound nearly identical to the original.

EDIT: if you want to just hack one side off the original enclosure and close it back up, the result will be a higher resonant frequency = bass won't be as deep.  You might be able to counteract this a bit by moving the port outside the enclosure, since it's volume is considered to be cutting into the volume of the enclosure.
Title: Re: Question about modifying a sub-woofer.
Post by: Howard_Casto on April 17, 2016, 12:17:40 pm
Ok so it's the volume.  That's what I needed to know.  I should be good then because a good 3rd of the cube is taken up by the amp and controls which are housed inside the sub.  I'm moving those to my control panel where all the knobs are handy. 

I guess the question then is where to mount it.  I have room in the slide out floor, but I'm also toying with the idea of putting it inside the seat.... with the horn sticking out the back.  I just wonder if the seat would absorb too much sound. 
Title: Re: Question about modifying a sub-woofer.
Post by: Howard_Casto on April 17, 2016, 04:39:31 pm
Thanks for the advice.  I messed around with it a little today and found with a slightly larger volume cube, the thing sounds much better than it does by default.  So I found a long flat box to test it in.... an old laptop box and it sounds so good I doubt I'll bother with making a wooden one. 

I went through my junk and man... I've got a ton of these 2.1 systems.  It's probably from when I used to do Halloween really big.  Every time I passed cheap speaker sets I would pick them up to use in props.  One of them has a super cheap sub in it, so I'm thinking of converting it to a butt-thumper. 
Title: Re: Question about modifying a sub-woofer.
Post by: BadMouth on April 18, 2016, 11:30:43 am
I guess the question then is where to mount it.  I have room in the slide out floor, but I'm also toying with the idea of putting it inside the seat.... with the horn sticking out the back.  I just wonder if the seat would absorb too much sound.

The Sega cabs had a little (4"?) woofer firing into the bottom of the seat.  It was about flush with the seat base, so there was a gap equal to the height of the seat sliders for the sound to escape.  Of course that was going into a plastic seat base.

IMO, your options are under the seat firing upward for the butt feel, or firing into the footwell for sound quality and deeper bass.
(the enclosed footwell will reinforce the sound and direct it toward you, much like the back window of your Camaro  ;D)

In your case, I'd probably just go with under the seat if that's where the most space is available.


.....AND DON'T SETTLE FOR A CARDBOARD BOX!
 
Title: Re: Question about modifying a sub-woofer.
Post by: Howard_Casto on April 18, 2016, 03:53:39 pm
I'll most likely do both.  I've got enough of the cheaper ones... time to get rid of some.  I'm honestly not sure if making a box is worth it.  The whole base is an enclosed wooden box.  I'm thinking of using a divider partition and just convert the back of the floor into a sub.  I'm going to put some kind of transducer in the seat as well.  I haven't decided if I'll have audio control it, or I'll hook it up as a rumble motor. 
Title: Re: Question about modifying a sub-woofer.
Post by: ant2 on April 22, 2016, 04:03:42 am
Once you transducer,  you never look back.