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pwmin
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well then if there is no vibration then I am all good. just thought I would ask because at first you sounded all militant about it. but good thing he isn't going to need a professional to do it then, because he is more of a DIY guy I think. and no professional would ever do that for him anyway...

 

 

 

yeah f-ing right.

 

No professional and reputable shop will mount an amp to the back of a sub for the reasons I mentioned above unless the customer insists on it and signs a waiver to void the warranty for the work performed. Its a bad idea and any experienced installer will tell you its a bad idea. Doesn't have to be a lot of vibration, even a little that's directly transmitted to the amp will do, especially if its bolted right to the sub box.

 

Here, try a test. Run a 100hz test tone in your car for an entire minute every day at max volume. Let me know how long that amp lasts you. Its a bad idea. Nothing to be gained. It will be as simple as solder joints breaking down. You don't have to shake it loose with mad amounts of low excursion bass. Its the higher frequencies that cause the damage.

 

Give me one legitimate reason to mount an amp to a box. I think when there's a risk involved, it outweighs any potential benefits.

 

You will search and find plenty of people that do it, but I personally lost an amp to that kind of crap and I know for a fact it wasn't a random problem, it was vibration related and Slick confirmed it because he knew it was mounted to a box.

 

I installed professionally for 10yrs and I would recommend to NEVER mount an amp to a box. The vibrations in time will ruin an amp. You will get a cracked solder connection in time plus its easier to steal your system when they just have to pick up the box and cut wires. If you dont have the box mounted then its sliding around in your trunk which can pull the wires and you can have a short with power and ground which can damage the amp or send a short to the radio thru the remte turn on.

 

Generally it's a bad idea to mount an amp to a sub box because the vibration can damage the amp. What happens usually is the solder joints will break in places and then the amp tech has to track down the breaks and repair them. But people do it all the time and many don't have the problem. To be safe it's better to mount the amp to the vehicle and not the box. If you ever need to remove the box you wouldn't be able to easily if the amp is mounted to it.

 

noo it will damage the amplifier wait let me think again

YES mount the amplifier to the box that way when the crook steal your box we will also take the amplifier ,make easy for the thief

 

And lastly:

 

http://www.bcae1.com/amplfier.htm

 

Amplifier mounting:

DO NOT mount an amplifier on your subwoofer box. I know that there has been a great deal of discussion over mounting an amplifier to an enclosure and many people do it all of the time with no problems but those people probably build good enclosures from 3/4" (or thicker) MDF with extensive bracing. Most people (especially young impatient people) are too lazy to do that and build unbraced enclosures from 5/8 MDF. These enclosures will flex considerably more than a proper enclosure and will likely cause amplifier failure if the amp is mounted to the enclosure.

REASON:

When the woofer(s) moves in or out, the box flexes and therefore causes the sides of the box to vibrate. This vibration is transferred to the amplifier mounted to the box. All of the electrical components in the amplifier have mass. Inertia (an object in motion tends to stay in motion, an object at rest tends to stay at rest) tells them to stay at rest, the box vibration is trying to make them move. The energy from the box's vibration is transferred to the components through the electrical leads which are soldered into the circuit board. All of this will cause the components to break loose and therefore cause the amplifier to fail prematurely. Basically, the amplifier will commit suicide! :-) I'm not telling you this because someone told me it was bad. I've been repairing amplifiers since ~1985. Virtually every amplifier that's come into my shop with parts rattling around inside them have been mounted on the speaker box. It causes the legs of the semiconductors to break (which causes amplifier failure). It causes the capacitors to break off of the board (which can cause catastrophic amplifier failure). It causes solder joints to break on the semiconductors mounted to the heat sink. It causes transformer windings to grind into one another (which causes lots of smoke to pour out of your amplifier). People who repeatedly tell others to mount their amps on the speaker box because they've never had a problem remind me of people who drink and drive and say there's nothing wrong with it because they've never crashed their vehicle. Eventually, in both cases, problems will arise.

 

NOTE:

Mounting the amplifier on the enclosure also allows someone to steal BOTH your amps and speakers at the same time with no extra effort. It's bad enough to have one or the other stolen but losing amps and speakers (and anything else mounted to your speaker box) is really gonna suck.

 

Not sure if I was clear or not on the topic, so I'll summarize.

 

Do not mount the amp on the sub box!

 

Even if your box is well braced and is solid, mounting the amp to the box still poses a risk that should be avoided if at all possible. There is absolutely no reason for it. Any vibrations the box creates are fed directly into the amp, and it **will** shorten the lifespan of the amp over time. It may not happen in 1, 2, or 3 years, but it will eventually happen.

Edited by xtremerevolution
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Here's the sub I recommend:

 

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-460

 

It competes well with the more expensive IDQ V3 on a few fronts, and while it doesn't sound quite as good, its more bang for the buck for sure. Its a huge favorite on diyma and is very well built. You'll need ~350w RMS at 4 ohms to power this. If in the future you want to upgrade, you can add a second sub.

That sure is one generic looking cone, lol, but I've heard good things about them. Why not this one, although it's more money? It says 1.0cf box vs. 1.5cf box http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-414

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That sure is one generic looking cone, lol, but I've heard good things about them. Why not this one, although it's more money? It says 1.0cf box vs. 1.5cf box http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-414

 

The higher Fs is what's throwing me off a bit. It will need a larger box than the other one I showed you. Vas is not the recommended enclosure size. Vas is the amount of airspace in an enclosed container that would equal the suspension stiffness of the spider on the subwoofer. The numbers help you determine a box size, but they don't specify the box size.

 

The Titanic sub is a different sub and is geared more for output than for SQ. Both would work, although the Titanic is also out of stock. If you're looking more for sound quality, I'd go with the Dayton HF.

 

If you want more output, the dayton HO is an option as well:

 

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-462

 

Looks the same, but it has a heavier, stiffer cone that can take more power and is a more high output sub compared to the other one I sent you. Not by a lot, but they're different in their own right. The lighter the better for sound quality, and don't get the impression it won't pound, because it will.

 

The Dayton HO and Dayton HF are also built around a lower distortion motor structure, while the Titanic is not. Just something to consider.

 

As for generic looking cones, well, yeah. Some of the most expensive speakers on the market come with very generic looking, but very amazing sounding cones. Kicker CVX subs for exmaple have much prettier looking cones but don't hold a candle to these.

 

Take these for example:

http://www.greenmountainaudio.com/rio/

 

Generic looking paper cones with a $2500 MSRP. I happen to have those cones as parts for building other speakers, and I can tell you they're lighter than most any paper cones I've ever seen. They're fragile, but extremely articulate, detailed, and accurate. They would blow you away. Its not a surprise the asking price is that high.

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I didn't see any other cf numbers, so I wasn't sure what to look at. I've built boxes before trying to use the recommended size, but I've never REALLY built a box. I just want a box built to spec that will fit under the STB and be out of the way of the pass-through and I'll build a shelf somewhere else for the amp. Are you thinking sealed? I've never built a vented enclosure and don't know much about them even though i've been installing stereos for like 13 years, lol, but mostly in my own cars. I'm definitely open to either the HO or HF...just don't know much about that brand or really what I'm looking for. Up to this point I guess I've never done the proper research on what I was buying except for HU's. The price for those subs is good, I just need to match an amp now. It's going to be more money for an amp that does 350 (or 600 depending on which one I get) @ 4 ohms verses the ones I was looking at @ 2 ohms.

 

edit: looks like I can't find an amp I can afford that will push 600W, so I'll probably have to go w/ the HF

 

 

 

I don't care about the cone, just commenting.

 

amp choices?...

Cadence: ($230) http://www.woofersetc.com/p-8330-fxa-1700-cadence-1400-watt-mono-amplifier.aspx

Crunch ($190) http://www.woofersetc.com/p-8749-pzt15001-crunch-1500w-max-power-zone-series-1-channel-monoblock-amplifier.aspx...probably not enough POWAH!

Hifonics ($230) http://www.woofersetc.com/p-9395-brz12001d-hifonics-1200w-brutus-series-1-channel-monoblock-class-d-amplifier.aspx

Hifonics ($210) http://www.woofersetc.com/p-8682-hfi1500d-hifonics-monoblock-1500-watt-hfi-series-amplifier.aspx

...I'll have to look some more, but not enough time at the moment

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I didn't see any other cf numbers, so I wasn't sure what to look at. I've built boxes before trying to use the recommended size, but I've never REALLY built a box. I just want a box built to spec that will fit under the STB and be out of the way of the pass-through and I'll build a shelf somewhere else for the amp. Are you thinking sealed? I've never built a vented enclosure and don't know much about them even though i've been installing stereos for like 13 years, lol, but mostly in my own cars. I'm definitely open to either the HO or HF...just don't know much about that brand or really what I'm looking for. Up to this point I guess I've never done the proper research on what I was buying except for HU's. The price for those subs is good, I just need to match an amp now. It's going to be more money for an amp that does 350 (or 600 depending on which one I get) @ 4 ohms verses the ones I was looking at @ 2 ohms.

 

edit: looks like I can't find an amp I can afford that will push 600W, so I'll probably have to go w/ the HF

 

 

 

I don't care about the cone, just commenting.

 

amp choices?...

Cadence: ($230) http://www.woofersetc.com/p-8330-fxa-1700-cadence-1400-watt-mono-amplifier.aspx

Crunch ($190) http://www.woofersetc.com/p-8749-pzt15001-crunch-1500w-max-power-zone-series-1-channel-monoblock-amplifier.aspx...probably not enough POWAH!

Hifonics ($230) http://www.woofersetc.com/p-9395-brz12001d-hifonics-1200w-brutus-series-1-channel-monoblock-class-d-amplifier.aspx

Hifonics ($210) http://www.woofersetc.com/p-8682-hfi1500d-hifonics-monoblock-1500-watt-hfi-series-amplifier.aspx

...I'll have to look some more, but not enough time at the moment

 

Don't stress over the box, I'll design it for you and give you the dimensions.

 

I'm definitely thinking sealed. Ported boxes will always be larger for a given sub. I know plenty about the brand, and they are extremely well built subs. They're solid and worth every dollar. They compete with subs more expensive than they are, and I would not hesitate to use one myself. Don't worry, you won't be disappointed.

 

Between the HO and the HF, if you're going for sound quality, the HF is your best option. Use the coupon code PESAVE5 for an additional $5 off. You really can't beat that.

 

I still need some dimensions from you regarding how much space you have to work with.

 

As far as amps, why buy new when you can buy Boston Acoustics refurbished amps? I actually bought two for my new Regal and they're in great condition. Plus, they still come with a warranty.

 

Either of these would work beautifully.

 

http://www.bostonacoustics.com/GTA-800M-Refurbished-P691.aspx

http://www.bostonacoustics.com/GT-2125-Refurbished-P692.aspx

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hrmm....http://www.sonicelectronix.com/item_22702_Hifonics-HFi2000D.html

 

Don't stress over the box, I'll design it for you and give you the dimensions.

 

I'm definitely thinking sealed. Ported boxes will always be larger for a given sub. I know plenty about the brand, and they are extremely well built subs. They're solid and worth every dollar. They compete with subs more expensive than they are, and I would not hesitate to use one myself. Don't worry, you won't be disappointed.

 

Between the HO and the HF, if you're going for sound quality, the HF is your best option. Use the coupon code PESAVE5 for an additional $5 off. You really can't beat that.

 

I still need some dimensions from you regarding how much space you have to work with.

 

As far as amps, why buy new when you can buy Boston Acoustics refurbished amps? I actually bought two for my new Regal and they're in great condition. Plus, they still come with a warranty.

 

Either of these would work beautifully.

 

http://www.bostonacoustics.com/GTA-800M-Refurbished-P691.aspx

http://www.bostonacoustics.com/GT-2125-Refurbished-P692.aspx

Don't think the one I quoted will work w/ the HO? Those two bostons will limit me to the HF, which is fine. I've been listening to a decent amount of mathcore and progressive/technical metal, which will work well w/ the 10 and should be fine for rap, too. Which one, the HO or HF would be better for that?

 

I'll take some measurement as soon as I get a chance...hopefully tonight. I'd like to try and order the amp tonight, too. Not sure if I'll buy the sub and amp right now or just the amp.

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your yelling at me for this is only making me more skeptical. my box is the most solid part of my vehicle to mount it to is why. the bass has messed up my amp from the bass waves when it was NOT mounted to the box. the reason the box is safer is because it was built to not flex. the body panels and windows vibrate, package shelf where the 6x9's mount buzzes and rattles. explain what to do now? hell, even the dash shakes when the bass hits, but I go put my hand on the box and its dead solid. :shrug:

 

the box is the only thing DEAD solid. and according to your logic that would be the BEST spot to mount it, wouldn't it? :think: sorry, real confused, so please if you could straighten me out on this one I would really appreciate it.

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Don't think the one I quoted will work w/ the HO? Those two bostons will limit me to the HF, which is fine. I've been listening to a decent amount of mathcore and progressive/technical metal, which will work well w/ the 10 and should be fine for rap, too. Which one, the HO or HF would be better for that?

 

I'll take some measurement as soon as I get a chance...hopefully tonight. I'd like to try and order the amp tonight, too. Not sure if I'll buy the sub and amp right now or just the amp.

 

I personally don't like Hifonics amps. I've used two of them and they've been excellently reliable, but just something about them doesn't appeal to me. I have read that they are a bit overrated as well, and at least in the last few years, they haven't been CEA-2006 certified. CEA Certification confirms that an amplifier can deliver its rated power at 14.4V below a certain level of distortion.

 

The GTA-800M will power the Dayton HO sub just fine. In fact, I think it would be an excellent combination. Keep in mind that between 500 and 600W on that sub will only increase your output by about 1db.

 

your yelling at me for this is only making me more skeptical. my box is the most solid part of my vehicle to mount it to is why. the bass has messed up my amp from the bass waves when it was NOT mounted to the box. the reason the box is safer is because it was built to not flex. the body panels and windows vibrate, package shelf where the 6x9's mount buzzes and rattles. explain what to do now? hell, even the dash shakes when the bass hits, but I go put my hand on the box and its dead solid. :shrug:

 

the box is the only thing DEAD solid. and according to your logic that would be the BEST spot to mount it, wouldn't it? :think: sorry, real confused, so please if you could straighten me out on this one I would really appreciate it.

 

Its likely your box does weigh a ton and a half given it supposedly has a 5" thick baffle, which might also be doing a great job of choking the sub by blocking the air around it, unless you took the time to chamfer a few of those layers. Even so, its still impossible for absolutely no vibration to be transmitted from a 1000W+ subwoofer to an amp that's bolted directly to the box. As for everything else flexing, I don't mount my amps to any body panels. They're mounted to carpeted MDF boards, which are then mounted to the body panels.

 

So you're basically telling me that if you pushed your sub to the utter limits and picked up the box, that it would have absolutely no vibration? I find that a bit hard to believe. Try placing a bowl of water on your sub box, running several frequency sweeps or songs with a wide range of bass notes, and take a video.

 

Its always safer not to mount the sub on the box. The vibrations you feel are from the sub's movement being transmitted through the box into the rest of the car. The sub/box as one are the source of the vibration. In other words, its the worst place to mount an amp.

 

But since you don't seem to like taking my word for things when I say them, I took the liberty of calling JL Audio's tech support myself. The number is here:

 

http://mobile.jlaudio.com/support_pages.php?page_id=130

 

I told the representative I just purchased a new JL 1000.1 and a JL W7 subwoofer, and asked if it would be recommended to mount the sub to the sub box. I quote the representative:

 

"generally we don't recommend mounting the subwoofer to the subwoofer enclosure because of the resonances created by the subwoofer. It can end up vibrating the amplifier apart internally. If you have a very solid box, you might be ok, but we generally don't recommend it."

 

The representative's name was Ward, in case you want to call to verify that information.

 

Out of curiosity, how much bracing do you have inside that box?

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Get creative and make some nice amp racks! Here's a few I did (when I was an installer several years back, been 3 years since I've done anything).

 

This amp rack was a fix to what was there. I wish he would have purchased all new wiring so I could have cleaned it up, but unfortunately, I had to work with what was already there.

IMG_0005.jpg

IMG_0002.jpg

IMG_1515.jpg

IMG_1514.jpg

 

Trailblazer (calling Jeremy!). Far from perfect, but again, limited on how much he wanted to spend.

kickerpanel.jpg

infinitypanel.jpg

wholetrunk.jpg

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I never said my 1000/1 was mounted on my box. I was saying that I was worried it got messed up by the BASS WAVES. no need to call JL about it, but you should have complained on behalf of my car's sheet metal and dashboard that got all shook up... since you had them on the line. :biggrin:

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I never said my 1000/1 was mounted on my box. I was saying that I was worried it got messed up by the BASS WAVES. no need to call JL about it, but you should have complained on behalf of my car's sheet metal and dashboard that got all shook up... since you had them on the line. :biggrin:

 

Bass waves (technically low frequency sound waves) don't mess up equipment. Its the direct vibration and shocks that mess up equipment, and improper installations.

 

I assumed you had yours mounted to the box given you appeared to disagree with me and claim that there was nothing wrong after I had explained it a few times.

 

Mount the amps to boards, and the boards to the car. If you're still worried about it, use rubber isolators.

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it messes up my equipment. the rearview mirror falls off. the keyfob brain rattles on the package shelf, the whole panel there warps violently. the 6x9's get messed with. other's cars around me visibly shake as well. I have to turn it way down to be not considered an ass hole at stop lights, while others taunt me to turn it up. its vicious. rubber isolators would be a drop in the bucket.

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Get creative and make some nice amp racks! Here's a few I did (when I was an installer several years back, been 3 years since I've done anything).

 

I made some pretty nice amp racks for my 96, but I probably don't feel like dicking with it too much, so a simple semi-hidden one is probably what I'm looking for.

 

nice installs, too

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I personally don't like Hifonics amps. I've used two of them and they've been excellently reliable, but just something about them doesn't appeal to me. I have read that they are a bit overrated as well, and at least in the last few years, they haven't been CEA-2006 certified. CEA Certification confirms that an amplifier can deliver its rated power at 14.4V below a certain level of distortion.

 

The GTA-800M will power the Dayton HO sub just fine. In fact, I think it would be an excellent combination. Keep in mind that between 500 and 600W on that sub will only increase your output by about 1db.

cool, I'll probably go with that then. I'll LYK if I decide to order the sub and amp or just the sub and some trunk dimensions. Thanks.
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it messes up my equipment. the rearview mirror falls off. the keyfob brain rattles on the package shelf, the whole panel there warps violently. the 6x9's get messed with. other's cars around me visibly shake as well. I have to turn it way down to be not considered an ass hole at stop lights, while others taunt me to turn it up. its vicious. rubber isolators would be a drop in the bucket.

 

Video or it didn't happen.

 

6x9's are very obviously in the range of damage from trunk pressures. AS for rearview mirrors falling off, I REALLY want to see this. I can yank on mine with all my might and it won't come off. A sub in the trunk isn't going to change that.

 

Its higher frequency induced vibrations that cause the most problems.

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One of my clients lost his rearview from 2 12s off 400w. its more in the mirror than the bass :lol:

 

Must be shitty mirrors. I had a 15" hifonics 1600w sub in the trunk for almost a year and my mirror is still intact.

 

Sent from my HTC Awesome using Tapatalk

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there you go, I don't need a video for proof. my girlfriend just walked by and confirmed it, she was there. she has been with me since I had the 1000/1 and w7 back almost 10 years ago. I use her memory sometimes because its much better than mine.

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Andrei, I attached a "drawing" of the dimensions of the spot where I want to put the sub box. I'm hoping there's enough room there to work with. I'd prefer to keep the front flush with the STB, but it's not completely necessary. IDK if the side needs to be trapezoidal or not.

post-738-143689069769_thumb.jpg

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Must be shitty mirrors. I had a 15" hifonics 1600w sub in the trunk for almost a year and my mirror is still intact.

 

Sent from my HTC Awesome using Tapatalk

 

That's my thought. Bad glue or something.

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Andrei, I attached a "drawing" of the dimensions of the spot where I want to put the sub box. I'm hoping there's enough room there to work with. I'd prefer to keep the front flush with the STB, but it's not completely necessary. IDK if the side needs to be trapezoidal or not.

 

That's confusing to look at, lol. Is that while looking into the trunk? Why did you make it trapezoidal at all? Give me a max height up to the strut tower bar, max width to the ski pass, and max depth.

 

Sent from my HTC Awesome using Tapatalk

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