Car audio gurus help a noob please

2k4_8

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So in this new durango there was an existing system minus the sub. I am in the middle of finding out what the hell everything is and what they run power wise etc so I can get a sub for her b day which is only about 2-3 weeks away.

So far I know it has an Alpine 98xx head unit, a rockford fosgate digital capacitor, 2 of these http://www.alphacaraudio.co.uk/images/OLDSITE/Hex600Family.jpg crossovers, and a kicker kx700.5 amp. The amp is what really has me fuggered up. I can't find out the output on this thing. It has six knobs on it and it says amp 1 and amp 2 for each of the three adjustments per amp. I pulled off the protective cover and it would seem that one of them is supplying the speakers and one is supplying the subwoofer that is no longer there. I finally found the amp http://www.lightav.com/car/kicker/amps4.html It's the one on the bottom. So what kind of sub does this amp run best as far as power? I am...as posted....a noob when it comes to audio so thanks for any help! :thumbsup:
 
Looks like it's a 5 channel of which 4 of the channels could be bridged down to 2 channels. The 5th channel would be the one to use for the sub (1x400w RMS). I would look for a sub that is advertised for that range (400w RMS), which is pretty healthy and should get you some good rattling going on. I prefer sealed enclosure subs.

good luck

P
 
I apologize I still don't 100% understand....are you saying it could be hooked up to the car speakers and STILL run the sub at 400 rms or is that if it is all hooked up to just the sub?
 
The sub channel is 400watts @ 2 ohms. Make sure you either get a sub that has a single, 2 ohm voice coil, and is rated at 400watts; or one with dual 4 ohm coils and is rated for 400watts @ 2 ohms. If you get a dual 4 ohm coil sub you'll have to wire the coils in parallel to drop the ohms down to 2 to get the most bang for your buck. You can leave it at 4 ohms, but you'll only be getting 200 watts worth of power.
 
I apologize I still don't 100% understand....are you saying it could be hooked up to the car speakers and STILL run the sub at 400 rms or is that if it is all hooked up to just the sub?

That's correct. The sub channel alone is a 400 watt @ 2 ohm mono channel. It is it's own channel. The other 4 are for the interior speakers, and the one is for the sub.
 
Thanks a million guys, I finally see the light! :cheerleader::lol::thumbsup:

Lol, no problem. Glad I could help. I'm in the process of upgrading the sound system in my car right now. Actually, all I'm doing is changing the sub enclosures. The ones that were in there were WAY too small, so I'm making some custom fiberglass ones. Just gotta get the body filler and paint done now. Do you know what speaker you're going to go with?
 
You would be better off getting a quality speaker that is rated at 300 RMS. You will go deaf before you kill the speaker. I would rather max out a speaker with clean sound, than destroy it with distortion because the amp ran out of juice. I have built a couple of extremely high end systems following this method. It has served me well.

BTW. A sealed box/speaker will give you bass with a more snappy impact. An open air type sub will give less accurate more boomy response. Open air is perfect for rap and most hip-hop. Almost everything else will sound better with a speaker enclosure.
 
You would be better off getting a quality speaker that is rated at 300 RMS. You will go deaf before you kill the speaker. I would rather max out a speaker with clean sound, than destroy it with distortion because the amp ran out of juice. I have built a couple of extremely high end systems following this method. It has served me well.

BTW. A sealed box/speaker will give you bass with a more snappy impact. An open air type sub will give less accurate more boomy response. Open air is perfect for rap and most hip-hop. Almost everything else will sound better with a speaker enclosure.

Why would someone who says they've built extremely high end systems say that a sub in the open air is just fine? I've never seen anyone use a sub in a car without a box, and I can't imagine it sounding very good at all. All car audio subs should be in a box. Sealed or ported will depend on the sub, but all subs that I can think of should be in a box. Also, the system will be just fine with a 400 watt sub. If that's what the amp can produce RMS you'll be fine. You won't get any clipping, and if you do, it won't be untill you get up toward the max output of the amp (the highest volume level of the head unit, if the gain is set properly) which you really probalby don't want to be at anyway. I'm running 2 subs each rated at 1100 watts RMS and 2200 watts peak with my amp bridged at 2400 watts @ 1 ohm mono. That means each sub is getting 1200 watts, and I've had no problems. I've also had the system for about 6 years.
 
Oh, and clipping (distorted sound) isn't caused by the amp not keeping up with what the speaker wants to do, it's caused by the amp being pushed too hard and creating square shaped wave instead of the sine wave (clean sound). The square wave puts double the power into the speaker, but the speaker isn't actually moving any more than normal, so it doesn't have any more airflow across the voice coil. This causes the voice coil to overheat and damages the speaker. The closer you get the speaker to the output power of the amp the lower your risk of damage will be. There's a website that explains this very well, but here is a little clip from it. It's from bcae1.com:

If your speakers are capable of handling significantly more than your amplifier can produce, driving them with a clipped signal will not likely hurt them.
If the speakers can handle 3 or 4 times the power that your amplifier can produce, there's virtually no way to damage your speakers (no matter how clipped the signal is).
If your speakers are rated for the same power handling as your amplifier is capable of producing cleanly, driving them with a clipped signal for extended periods of time may cause speaker damage and/or premature failure.
If your speakers are rated for the same power handling as your amplifier is capable of producing cleanly, driving them with a square wave signal for extended periods of time will likely cause speaker damage.

So basically, as long as you don't run the amp as hard as you possibly can, all the time, you'll be ok.
 
get a kicker sub. they are some of the best. that amp is great but i didnt know kicker make a 5 ch amp. as far as "open air" i believe he is referring to a ported box or a bandpass box which is probably what u will need since u dont have a trunk
 
"Open air is perfect for rap and most hip-hop. Almost everything else will sound better with a speaker enclosure."

He didn't say sealed enclosure. Also, being as he's installed a couple "extremely high end" systems, I'm sure he knows the lingo.
 
get a kicker sub. they are some of the best. that amp is great but i didnt know kicker make a 5 ch amp. as far as "open air" i believe he is referring to a ported box or a bandpass box which is probably what u will need since u dont have a trunk

That amp, from what I can find has actually been discontinued, so they may not still make a 5 channel. As far as the box goes, it's completely dependant on the sub and the frequency response that you want. Not the vehicle. Sealed boxes are smaller in size, and will hit a fairly good frequency range, but they won't go as low. A ported box will give more on the low end. A bandpass box can sound good and give a flat response, but most do not. They're designed to impress you in the store meaning they'll give a large peak at around 60hz. If she ONLY listens to rap, it will work ok, but won't sound good with anything else. When you get your sub it will have enclosure information such as, type (ported or sealed), sub displacement, port size and displacement(if aplicable), and cu ft of volume needed so that you can build it to make the sub sound it's best. If you don't have time, or don't feel like building one you can go to any car audio installation shop and either buy one outright or have them build you one to your speaker's specs.

and spend the money for really good rca's, gound, and power wires

+1 on this, but from your first post it sounds like everything is already wired, you just need the sub, right?
 
Pardon my typing if I poorly worded my first post. I didn't realize the internet police were that bored tonight.

When I say "open air" I mean the speaker, not the enclosure type. All open air speakers need a lot of air movement to operate as designed. The reason why you don't see them much in high-end car systems is because they require more air space to operate than most cars can provide. They also are built with a more rigid surround and cone to prevent damage from excessive travel. Go look at concert speakers that have a folded duct, and are not sealed enough to support for the more flimsy sealed box speakers.

Sealed (includes ported boxes) speakers will always outperform open air speakers in a car because they require less space to perform as their best. In a conventional box they do pretty well if they have enough volume of space to travel enough, but not big that they don't build enough back pressure or vacuum to keep from running beyond the designed travel. The biggest problem most installers make is putting a speaker in too small of an enclosure. You need to over-drive the speaker for it to sound decent.

As far as ported vs sealed, a ported box is a sealed box with a tuned "leak". You tune the box by the port size and length in relation to the volume of the sealed enclosure.

Now let's discuss amps. When you see an amp rated at 400 watts RMS, what is the amount of distortion when it reaches 400 watts? You will get the lowest distortion in the first 80% of all solid state amps. Look at the distortion graph from a reputable manufacture and you will see what I mean. That is why I suggest the lower powered speakers. When you reach the speakers maximum you should not hear any audible distortion.

The head unit, pre-amp crossover (if used) and interconnect wires are also very important for sound quality. Your sound system will only be as good as the dirtiest sounding component.

And by high-end systems, I mean award winning ground-pounders that could pump out a deafening 145+ db SPL (sound pressure level). I designed and built one system with two 10" subs (120 watts RMS) in a custom box, powered by an amp bridged mono with an output rating of 320 watts RMS @ 2 ohms, producing 136 db SPL @ less than 2% distortion at a car stereo sound off in Colorado Springs. I have built many more systems to the customers specifications that sounded like garbage compared to a properly though out system.
 
A local audio shop gave me a quote for a powerbass 12" (since she mainly listens to hip hop and some dance technoish music...primarily the top 100 hip hop type stations and 80's music) in a box, installed and tuned for like 150...and I think it was a 300 or 350 rms sub? But I kinda had settled on a 12 since she doesn't listen to rock or anything.

Oh, and as far as wiring goes, it appears to have quality RCA, they look like a good quality solid set at least.
 
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who needs amps and speakers I listen to my car... 67 PLymouth Valiant 408 C.I. Headmen Headers Flowmaster Exhaust..yeah baby!!! the one doing the wheel stand is not mine but but my friends, I'm standing next to mine

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A local audio shop gave me a quote for a powerbass 12" (since she mainly listens to hip hop and some dance technoish music...primarily the top 100 hip hop type stations and 80's music) in a box, installed and tuned for like 150...and I think it was a 300 or 350 rms sub? But I kinda had settled on a 12 since she doesn't listen to rock or anything.

Oh, and as far as wiring goes, it appears to have quality RCA, they look like a good quality solid set at least.

From what I can tell, that sub seems to be a decent sub. That's a good deal at 150 for the sub, box, installation, and tuning. I think she'll be pretty happy with that setup. As far as RCA's, as long as they're designed for car audio and not home audio you should be fine. The person that originally installed the system most likely purchased an amp kit with it (which would include all the power, ground, remote, and RCA's) so you should be fine with that.

TruWrecks:
I wanted to apologize for a couple of my posts last night. You obviously have a lot of experience with this stuff and my "bashing" you, if you will, wasn't neccissary. I missunderstood what you had said, and so I thought you were wrong. I was tryin to use some of the knowledge I've gained over the years to help him out. I re-read my posts today and I see now that I kinda came across as an azzhat. It was late and I was tired and a little frustrated at the time. So for my posts last night that may have made it sound like your (or anyone else's) posts were insignificant... I apologize.
 
TruWrecks:
I wanted to apologize for a couple of my posts last night. You obviously have a lot of experience with this stuff and my "bashing" you, if you will, wasn't neccissary. I missunderstood what you had said, and so I thought you were wrong. I was tryin to use some of the knowledge I've gained over the years to help him out. I re-read my posts today and I see now that I kinda came across as an azzhat. It was late and I was tired and a little frustrated at the time. So for my posts last night that may have made it sound like your (or anyone else's) posts were insignificant... I apologize.

It's all good! :beerchug:
 
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