Hey it's been awhile since I've posted here. How is everyone? Of course I need you guys to give some input. I'm building a fiberglass enclosure for my corolla. I taped the entire trunk with the blue painters tape, I've spray glued layers of foil over that. I lightly coated it with vasoline and layed a couple layers of mat and resin down. How do I know when to pull the form out of the trunk? How many layers of mat should I use? It's hard to tell how thick it is everywhere. Any suggestions would be appreciated.
Replies (11)
ravin on 08/10/2007 14:10:58
No worries I managed to get the forms out safely. I was having one of those "oh s*$t" moments. This is my first fiberglass project and mid way I think I scared myself. All good now. HAPPY
swez on 08/10/2007 16:01:04
That's good as our resident glassing experts are off on vacation at the moment. Thickness, I believe for subs, a 3/8" thickness or a tad more is usually sufficient.
Swez
ravin on 08/10/2007 17:59:55
Thanks Swez. I still have a lot of work left to do. I'm building two sub boxes on the opposite sides of the trunk. They will hopefully be removable so I can utilize that space when necessary. Thanks for the info. I may post some pictures when finished.
swez on 08/10/2007 20:58:57
Ravin,
As you fabricate, think about the firing angles of your subs. If at all possible, fire them toward the front of the car and not directly toward each other.
Subs that fire at each other, tend to cancel each other out.
Comments,
Swez
Ash on 08/10/2007 21:44:42
He is right about the cancellation. A friend insisted I install his subs the same way. The results weren't good in my eyes (or ears perhaps). The trunk still pressurized, but it wasn't a smooth sound in the cabin. There was more goings on in the trunk than there was bass in the car itself.
Someone stole that setup (trunk rattle advertising), and do you know that fool still wants the same thing!
ravin on 08/11/2007 00:10:46
I was planning on angling them slightly towards the rear and maybe a little up. Would that be okay? I was going to angle the port towards the rear as well. If you have any ideals of what would be better let me know. Thx!
swez on 08/11/2007 00:24:04
My gut reaction is to suggest using only one strong sub for this small car. That's cheaper, less work and no cancellation problems to deal with.
With the plan you have now, you won't know how good/bad dual subs sound in this project until it's too late. (Bought 2 subs, fabricated a lot and results are iffy at best.
Here, a few pics or a diagram of your proposed intall would be most helpful. One cannot post them directly to this site, but can be done using Power Point or MS Paint and shared via e-mail or other sites that allow such things.
If you must use dual subs, we really need a better picture than words can deliver. One thing you will want to avoid is subs facing each other and firing right at each other. <.................> Terrible cancellation issues are likely.
Swez
ravin on 08/17/2007 13:52:21
Sorry its taken so long to update. Here are some pics on my cardomain. I have committed to the speaker angle and port angle on one box and right now only have plans on finish it first before beginning to finish box two. I will add some newer pics to show the angles I have committed to if you can help me decide on angling for the other box.
http://www.cardomain.com/ride/2476188/2
swez on 08/17/2007 16:03:26
Nice masking job so far and that port is awesome. So far, so good.
In the pictures, I can't get the bigger picture on the sub firing angles you have planned. As you get the 1st side done, try to aim the sub toward the upper center of the rear trunk lid. (Just above the trunk latch should be good) If you can get that angle on both sides, it should work out well for you.
Tech Tip: When doing cross-firing/angle-firing sub installs, we know we have a good install when we only use 1 sub to reference and then add the 2nd one in unison. If we note fuller, deeper bass than with just 1 sub playing, it's been done well. If bass dB's drops or it sounds hollow and not as strong, this is evidence of severe cancellation problems and need to be corrected.
Keep us posted on your progress OK?
Swez
ravin on 08/18/2007 11:51:53
I will keep you posted. I'm going to try the firing angles that you mentioned. So I should aim them slightly up but more to the back center of the trunk just above the latch right? I will mock up my rings and post new pics.
swez on 08/18/2007 16:33:32
Try to aim them low on the trunk lid and right at the latch if possible. That's a good focal point reference as both subs will be in phase and minimal cancellations that way.
Have noted that the truck lid is a lousy reflector and will rattle a lot if not well matted too. Rattling trunk lids sound like hammered poop and we lose a lot of SQ bass in the process too. You may need to add matting and dampening materials anyway, (trunk lid) but that all depends on the resonance and how the trunk lid is braced.
Keep us posted on your progress,
Swez
Replies (11)
ravin on 08/10/2007 14:10:58
No worries I managed to get the forms out safely. I was having one of those "oh s*$t" moments. This is my first fiberglass project and mid way I think I scared myself. All good now. HAPPY
swez on 08/10/2007 16:01:04
That's good as our resident glassing experts are off on vacation at the moment. Thickness, I believe for subs, a 3/8" thickness or a tad more is usually sufficient.
Swez
ravin on 08/10/2007 17:59:55
Thanks Swez. I still have a lot of work left to do. I'm building two sub boxes on the opposite sides of the trunk. They will hopefully be removable so I can utilize that space when necessary. Thanks for the info. I may post some pictures when finished.
swez on 08/10/2007 20:58:57
Ravin,
As you fabricate, think about the firing angles of your subs. If at all possible, fire them toward the front of the car and not directly toward each other.
Subs that fire at each other, tend to cancel each other out.
Comments,
Swez
Ash on 08/10/2007 21:44:42
He is right about the cancellation. A friend insisted I install his subs the same way. The results weren't good in my eyes (or ears perhaps). The trunk still pressurized, but it wasn't a smooth sound in the cabin. There was more goings on in the trunk than there was bass in the car itself.
Someone stole that setup (trunk rattle advertising), and do you know that fool still wants the same thing!
ravin on 08/11/2007 00:10:46
I was planning on angling them slightly towards the rear and maybe a little up. Would that be okay? I was going to angle the port towards the rear as well. If you have any ideals of what would be better let me know. Thx!
swez on 08/11/2007 00:24:04
My gut reaction is to suggest using only one strong sub for this small car. That's cheaper, less work and no cancellation problems to deal with.
With the plan you have now, you won't know how good/bad dual subs sound in this project until it's too late. (Bought 2 subs, fabricated a lot and results are iffy at best.
Here, a few pics or a diagram of your proposed intall would be most helpful. One cannot post them directly to this site, but can be done using Power Point or MS Paint and shared via e-mail or other sites that allow such things.
If you must use dual subs, we really need a better picture than words can deliver. One thing you will want to avoid is subs facing each other and firing right at each other. <.................> Terrible cancellation issues are likely.
Swez
ravin on 08/17/2007 13:52:21
Sorry its taken so long to update. Here are some pics on my cardomain. I have committed to the speaker angle and port angle on one box and right now only have plans on finish it first before beginning to finish box two. I will add some newer pics to show the angles I have committed to if you can help me decide on angling for the other box.
http://www.cardomain.com/ride/2476188/2
swez on 08/17/2007 16:03:26
Nice masking job so far and that port is awesome. So far, so good.
In the pictures, I can't get the bigger picture on the sub firing angles you have planned. As you get the 1st side done, try to aim the sub toward the upper center of the rear trunk lid. (Just above the trunk latch should be good) If you can get that angle on both sides, it should work out well for you.
Tech Tip: When doing cross-firing/angle-firing sub installs, we know we have a good install when we only use 1 sub to reference and then add the 2nd one in unison. If we note fuller, deeper bass than with just 1 sub playing, it's been done well. If bass dB's drops or it sounds hollow and not as strong, this is evidence of severe cancellation problems and need to be corrected.
Keep us posted on your progress OK?
Swez
ravin on 08/18/2007 11:51:53
I will keep you posted. I'm going to try the firing angles that you mentioned. So I should aim them slightly up but more to the back center of the trunk just above the latch right? I will mock up my rings and post new pics.
swez on 08/18/2007 16:33:32
Try to aim them low on the trunk lid and right at the latch if possible. That's a good focal point reference as both subs will be in phase and minimal cancellations that way.
Have noted that the truck lid is a lousy reflector and will rattle a lot if not well matted too. Rattling trunk lids sound like hammered poop and we lose a lot of SQ bass in the process too. You may need to add matting and dampening materials anyway, (trunk lid) but that all depends on the resonance and how the trunk lid is braced.
Keep us posted on your progress,
Swez
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