Car Audio

[mootsfox]

Alishe, that's excessive. I'll post pictures of my truck, and a proper stereo system.

[Valor]

[QUOTE=Alishe;2702459]Kenwood 6.5in components; Rockford Fosgate 400watt 4channel amp.
You'll love it.

This is what I have;
http://i2.photobucket.com/albums/y1/...s/IMG00071.jpg

Please tell me that isn't your amp mounted to the sub box... Maybe I'm tired and I can't see straight but that's what it looks like...

As far as amps go, I've had great luck with zapco and arc audio. They are both products of Robert Zeff, an epic automotive amplifier engineer, and are made in the U.S.

You can also get some decent bass to balance out the mids/highs with something as small and compact as a well powered 10" sealed woofer. I even have a friend who runs a pairs of 8" subs and his setup sounds amazing. It's very precise and accurate and is not boomy at all. Pretty much what people said above is true as well. A decent set of components and a 4 channel amp will make a noticeable improvement.

[Kyten]

What's wrong with the amp on the box?

[Cyn]

What's wrong with the amp on the box?

Thieves get a hard on for amps mounted to boxes instead of bolted to the car for one.

[Valor]

What's wrong with the amp on the box?

Would you mount any other piece of electronic equipment to a surface that vibrated and shook as much as a sub box does? Electronic devices (even the ones designed for cars) are not designed to tolerate extended periods of vibration and stress that comes from being mounted to something like this. Never... never... never... mount an amp to a sub box... unless of course you are happy replacing your amp whenever it goes out.

[Cyn]

Would you mount any other piece of electronic equipment to a surface that vibrated and shook as much as a sub box does? Electronic devices (even the ones designed for cars) are not designed to tolerate extended periods of vibration and stress that comes from being mounted to something like this. Never... never... never... mount an amp to a sub box... unless of course you are happy replacing your amp whenever it goes out.

That's true in most situations, but if the box is good and it's going into a pickup truck (where you'd be screwing it into sheet metal right beside the box anyways), doesn't really matter much.

But yeah, still shouldn't mount to the box if you can avoid it, makes it much easier to steal both components.

[Valor]

That's true in most situations, but if the box is good and it's going into a pickup truck (where you'd be screwing it into sheet metal right beside the box anyways), doesn't really matter much.

But yeah, still shouldn't mount to the box if you can avoid it, makes it much easier to steal both components.

This is actually a little incorrect. The problem with the box itself is that it not only vibrates, but the wood (or fiberglass or whatever) actually flexes and changes shape. The sheet metal, while still vibrating some, will NOT flex in the same way that the wood will. Most boxes aren't any thicker than 3/4" and actually have a pretty noticeable amount of flex. I also don't recommend mounting directly to the sheet metal either. I typically use a sheet of mdf to mount the amp to and then make some brackets to mount it to the sheet metal with some small rubber bushings in between the wood and the body.

You can also think of it like standing beside your dryer in your house. If you sit on the dryer while it is on, the vibration is much more than if you sit on the ground directly beside it. Admittedly, there are some problems with this model, but it is the simplest one I can think of right now. The idea is to have the amp mounted to something with as little vibration as possible while still being as close as possible to the woofer. In tight areas this becomes very tricky. However, coming up with a solution without mounting to the box is ALWAYS the preferred solution. Many amp manufacturers won't even warranty their amps if they know you mounted it to the box.

[Gadritan]

^

This man speaks from experience.

On a side note, coating the interior of a wood box with a 1/4" layer of fiber glass helps reduce some of that flex in boxes. It improves the response quite a bit, which in turn increases the overall quality of the sound.

One of my buddies showed me that years ago. It's the only way I build them now.

[Valor]

Is it bad when I can smell resin whenever people talk about fiberglass?

Yes, coating a box in fiberglass can definitely help response, especially if your box is a bit further out of spec than it should be. I used to be one of those people that just built the boxes however I thought they would sound best, but over time I've come to realize that the people who make the speakers probably know what they are talking about, lol. I try to hit the specs as dead on or as close as possible and usually double baffle the front of the box if there is room.

If you do the fiberglass shell, you definitely have to make it thick. I always try to make the fiberglass thick enough so I could hypothetically stand on it. I'm sure it's a totally arbitrary depth, and I'm sure it is totally overkill, but once you have something you built, sanded, prepped, re-sanded, primed, and painted crack, you start getting paranoid. Lol. I've heard that some people even use kitty hair (silly imo) to do the whole shell if just coating a wood/mdf/etc box. *shrug*

Edit: Also, I find doing a shell turns out much better if I staple the first layer to the box at regular intervals using a pretty stout staple gun so they go in all the way or very close. MDF can be tough on staples, lol.

[Gadritan]

Yes, coating a box in fiberglass can definitely help response, especially if your box is a bit further out of spec than it should be.

That's exactly why I started doing this. Most people want custom boxes that look the way they want, and don't understand that the dimensions of the box are absolutely critical to the sound since the speakers are designed for a specific amount of air space.

So a fiberglass shell was a nice compromise to keep the customers happy with a great look while maintaining great response.

[Valor]

Customers are exactly why I don't do this kind of work professionally any more. I have a very very low threshold for stupidity and there are a limited number of times I can build "a box to hold 8 'by-nines' for my back seat." It's just not worth it for me. I'd rather do something different than build crap, lol.

[Cyn]

^

This man speaks from experience.

On a side note, coating the interior of a wood box with a 1/4" layer of fiber glass helps reduce some of that flex in boxes. It improves the response quite a bit, which in turn increases the overall quality of the sound.

One of my buddies showed me that years ago. It's the only way I build them now.

That's a technique from pro audio, you line subwoofer boxes with like R33 or something to increase response and reduce vibration. The funny part is that I've seen many situations where a 2x18" box is actually vibrating significantly less than the closest wall.

3/4 MDF is pretty stout though, and as long as you don't do anything silly like mounting the amp in the dead center of the largest side (where it will flex the most), a couple 12"s are not really going to eat the amp alive like you're suggesting. In fact, self powered professional speakers (like JBL Eons etc) ALL have amps mounted either inside the box or in a recess on the box, subs included.

But it's moot, I definitely agree that you shouldn't be mounting to the box in a car either way.

[Gadritan]

Yeah. I quit doing it when I was 20.

The last straw was when I had a jackass cuss me out because the wires were "showing" from the amp and he wanted them all hidden. He was talking about the roughly 1/2" amount of wire that connects to the amp itself. Not to mention this was after he refused my suggestions on hiding the amp from view entirely. He wanted people to see it to show off. Idiots like this are the ones who get all their shit stolen and wonder why. Not to mention he was 16yrs old spending $3k of his daddy's money on the Escalade his fucking daddy bought him.

[Valor]

That's a technique from pro audio, you line subwoofer boxes with like R33 or something to increase response and reduce vibration. The funny part is that I've seen many situations where a 2x18" box is actually vibrating significantly less than the closest wall.

3/4 MDF is pretty stout though, and as long as you don't do anything silly like mounting the amp in the dead center of the largest side (where it will flex the most), a couple 12"s are not really going to eat the amp alive like you're suggesting. In fact, self powered professional speakers (like JBL Eons etc) ALL have amps mounted either inside the box or in a recess on the box, subs included.

But it's moot, I definitely agree that you shouldn't be mounting to the box in a car either way.

Yeah... acoustics is a very interesting subject. I actually considered going for a masters in acoustics at one point, but I couldn't really find enough jobs out there to justify it. Self powered speakers have always been somewhat of a mystery to me. They violate everything my logical engineering brain says is "right" about designing things to last. I've never taken a modern one apart before, but perhaps they have some sort of floating mount setup inside the case for the amp. Or, maybe they don't have a lot of non-integrated pieces to rattle off. Once again, I have to defer to the experts on this one. They do this for a living, so it must have a low enough failure rate in the warranty period to be acceptable. Personally, I like to have very nice equipment that I never replace. I'd rather spend 1k bucks on a Zapco and never replace it than 300 bucks a pop on something that is made with less precision or out of lower quality components. (I also like that you can get these people on the phone for support and custom amplifiers). Sure, mounting it to the box is acceptable in the sense that it will work and it might work for a while. I'm just cranky and set in my ways about the "right" (and somewhat subjective) way to do things. I also hate to not say something and then hear about people having to replace things prematurely. It makes me a sad panda by proxy. Lol

[Kyten]

The only place I had to put my amp was on my box because my trunk is so small.

[Valor]

The only place I had to put my amp was on my box because my trunk is so small.

Or... just to be a dick here... your box is too big. Also, you can many times find mounting spots underneath seats and whatnot. I've even seen some pretty nice installations underneath the front dashboard. Small spaces are tricky sometimes, but if I can manage to fit 2 8" subs, a set of components w/ crossovers and two amps into a lotus esprit w/out mounting anything to the sub box (which btw was inside the passenger cabin w/0 loss of space), it can be done. It just takes some ingenuity.

[Kyten]

My trunk is stupid small, and my box isn't all that big either. But fuck it too lazy to move that shit.

[Gadritan]

Yeah. Sometimes you just gotta' think outside of the box. Literally and figuratively. lol

[Kyten]

When I get a new vehicle though, gonna make sure the trunk is a decent size haha.

[Cyn]

Hell, underneath the seat is like the best place ever for a 4way running your mid/highs. And using that spot for subs is easy, either way you're running wires from the front of the car to the trunk, doing it under the seat just changes it from power and signal to speaker wire.