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Discussion Starter #1
Can one of you audio guru explain the ohms issue as it applies to stereo and speakers.

I know that my stock system has 2 amps located in the trunk fastened to the top. One for the front and one for the back.

They are made by Clarion I believe. My stock speakers are also Clarion. I ordered new one last year from the Dealership and the sounded great compared to the worn one I had before.

One of the back speakers is rattling becuase it is cracking or has a hole I believe. My front speakers sound ok but like the bass of the back. ( I guess becuase they are 4x6 vs 6.5 )

My head unit is a Rockford Fosgate that plays great. Should I :

1)Find better 2 ohms aftermarket speakers
2)Get new amp and all new 4 ohm speaker
3) Listen to my mp3 player with my headphones

I am not looking to rattle the block just clean sound that I can hear with the windows down driving 55 mph


Thanks
 

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Discussion Starter #2
I did the front door conversion from stock 4x6 to Kenwood 6.5's. It sound very weak. I suspect this is because the stock amp is 2 ohms and the stock speakers were too.

The sound much more clear with high but it lack punch big time ....
 

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yeah your probably right, because Tweeter tested my stock bose system and it showed that my system was a 2 ohm system. so that means the amp was also pushing 2 ohms. so basically putting those 4 ohm speakers in, its not pushing its rated power. so basically you got 2 options...

1) keep your stock amp and get all 2 ohm speakers. theirs a few companies out there that provide these. which means selling your current kenwoods or...

2) just get a decent 4 channel amp to push all your speakers. like a kac-649, kac-749 or kac-849 for instance, if you wanna stay with kenwood.

i'd go #2

btw, what model kenwood speakers did you get? and is it just the fronts you got or all 4? :asian:
 

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Discussion Starter #4
I have the KFC-1677 Kenwoods only for the front but I now can hear all the speakers going bad .... man I am not an audio buff but the cracking back speakers now really sound like crap.....

I guess I need to find a 4 ohm amp and new speakers for back.

How hard its it to change the amp in P10 ? I need some simple plug and play thing else Circut City is going to get my money ...

http://www.epinions.com/613522_Kenwood_6_2_Way_Speakers_KFC_1677
 

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You guys are missing a few other options here...

First, i think he may need a little more clear explanation of how Ohms affect car audio to make an informed choice.

Bascially, every speaker has an electrical impedance measured in Ohms (named after the guy who figured this stuff out). Most home speakers are 8 Ohm and most car speakers are 4 Ohm (i don't know about the stock P10 system). Also, amplifiers have an Ohm rating as well. The rating on the amplifier isn't how much impedance it has, but how much impedance it is designed to deal with. Some amps will allow you to run them lower than their rated Ohms. Some very high quality amps let you run down to 1 Ohm or even .5 Ohms. The adavantage of doing this is, as Ohms go down, power goes up. An amp rated at [email protected] Ohms will run [email protected] Ohms (assuming the amp can handle 2 ohms without frying). So, an amp with a 4 Ohm rating is designed to have a 4 Ohm load (but *may* be able to handle a lower impedance). Generally, that means that you hook up one 4 Ohm speaker to each channel.

However; there is another option. If you wire two 2 Ohm speakers in series, you get 4 Ohms. If you wire two 8 Ohm speakers in parallel, you get 4 Ohms.

So, assuming the comments on here are correct, and the P10 stock amps are designed to run 2 Ohms, you have several options.

1) Find some 2 Ohm speakers to replace the 2 Ohm speakers that are blown.
2) Get some 4 Ohm speakers (two for each one you are replacing) and wire them in Parallel.
3) Replace your amps AND speakers (and probably head unit)

#2 will be the cheapest and easiest. Instead of just replacing your stock 2 Ohm speakers with aftermarket 2 Ohm speakers (which you're going to have a very hard time finding anyway), replace them with 4 Ohm speakers. Then, wire up another 4 Ohm speaker/sub in parallel. That way you're still running 2 Ohms, but you're getting more sound because you've got twice as many speakers running. The only real drawback to this is that you're dividing the wattage. Assuming the stock amp is 25W/channel (i don't know how much it is, this is just a guess), you're sharing 25W between two speakers. The stock setup runs 2 Ohms, and sends 25W to each speaker. The setup i've just described with two 4 Ohm speakers would be running 2 Ohms, just like stock, but would be sharing 25W between TWO speakers. That should still be enough wattage for the system to sound similar to stock. Also, if you get speakers that have a high sensitivity rating, you'll get more sound out of each speaker than the stock system.

The big advantage to going this route is price and ease of installation. You only have to buy 4 speakers (even relatively inexpensive ones will do) and a little wire. And there is almost no wiring to be done. Just hooking up the speakers in parallel. You don't have to buy a new amp (or go through the nightmare of powering and wiring it).

Of course, you could always just post in the Classifieds section and buy someone's stock speakers for cheap.
 

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Discussion Starter #6
Wow thats alot of information thank you.

If I do option #2 and run 2 speaker in parallel for both the driver side and passenger side, where am I going to place these extra speakers ?

Should I just screw them in the door panels ?

The back speaker are blowing surely too becuase I can hear the rattleing starting. Can i just run wire to a sub from under the trunk ?

( ps I had all new stock speakers installed less than year ago, Spounded great at first and now so no one else go this route on a P10 )

Sorry if this seems like dumb questions ,,,,
 

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your right 2 speakers take up too much space and will probally demand more power than the wimpy stock amp can give. BUT..remember tweeters are low wattage drivers too. You can buy some tweeters and float each tweeter by a speaker and wire them in parallel. This should give you a 2ohm load and won't ask for as much power as 2 fullsize speakers per channel. I used to know of a way to accurately measure the ohm load...I remember using a basic multimeter used for checking voltage etc. and setting it to the ohm setting connecting it to the speakers as if the meter was powering them and gently pushing on the cone. I think a 2ohm load will fluxuate from -2.0 to 2.0 on the reading. I think thats right...can someone confirm that. You'll be suprised how a little wiring can make a big difference in output. U.S. Amps makes a tiny high current amp thats can run a 1/4ohm load stable pushing close to a 1000watts but if you just hooked up some standard 4ohm speakers to each channel it only puts out 12.5watts. Well, IMO go option 2 route. You can do it on a budget by buying an used quality amp in a local recyler and buying some entry line aftermarket speakers at a chain store like Good Guys with an extended warrantee so you can abuse the heck out of them for years.
 

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Discussion Starter #8
Thanks again for all the information.

I actually work in a nuclear power plant on occasion and there is less information to diseminate there than to wire a stereo in a G20 ...lol.

So with option #2, I need to by tweeters ( ps what about the one in my pillars built it ). And I still need extra tweeter for the back also ?

I have a nice Rockford Fosgate Headunit that pushed like 4.5 volts to the amp I believe. It is rated at 40 watts per channel. I like it and dont want to part with it.

Considering that I already have the 4 ohm Kenwood for the front ( ps they sound bad ass in my girlfriend Altima ) what is the fastest cheapest way to get my stereo sounding good for under $ 200 ?

Thanks again guys....
 

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Remember that you don't HAVE to run your stock amp at 2 Ohms. If you don't it'll still work, you'll just be pushing 1/2 as many watts as the amp is rated at. So, if you want to save some money, you can just use 4 Ohm speakers. But if you use two sets of 4 Ohm speakers, you'll be able to play it louder because you'll have twice as many speakers, even though each speaker will be running 1/2 as many watts as the stock system.

Here's an option if you want new speakers and want to make sure you're running the stock amp at it's fullest:

Get two 4 Ohm speakers for the rear deck
Get one dual-voicecoil sub for the rear
Use your two existing 4 Ohm Kenwood speakers in the front
Get two 4 Ohm tweeters for the front (assuming the stock ones aren't 4 Ohms).

Wire the Kenwood door speakers in parallel with the tweeters (that will give you the desired 2 Ohm load).
Wire the new 4 Ohm rear speakers in parallel with the sub (again, you'll be running the desired 2 Ohm load).

I'm not sure how many watts the stock amp is rated at, but let's assume it's 25w X4 channels @ 2 Ohms (someone correct me if i'm wrong). If you wire things as i stated above you'll be running ~12 watts to the front tweeters, ~12 watts to the front door speakers, ~12 watts to the rear deck speakers, and ~25 watts to the sub (12w per voice coil). That's not a whole lot of wattage per channel, but it's enough to sound okay at "normal" levels. And you could always upgrade to a bigger amp down the road (assuming your speakers can handle the additional wattage). This is a relatively low wattage system, but it should still sound decent as long as you don't try to push it too loud. The sub will help fill in the low range, but don't expect too much punch with only 25 watts (and make sure you get someting with a very high efficiency).

Basically, you've got a LOT of options here. It all comes down to budget, really.

If you only have $200 to spend, i'd suggest you buy new rear speakers to replace the blown ones, some decent speaker wire, a soldering iron, solder, flux, and shrink tubing. If you have any money left save it to go toward a small subwoofer (8" or 10" maybe) or tweeters.

I would double-check the tweeters to see how many Ohms they are. It's possible that the stock system uses 4 Ohm speakers in the front (since there's two pairs) and 2 Ohms in the rear. Again, i'm not sure of the specs on the stock system but it's better to double-check and not spend money on new tweeters if you don't need to.

It would be great if we could find out the exact Wattage of the stock amp, the exact Ohms of all the stock speakers, and how the whole system is wired. That would make all of this a lot easier and would be great FAQ material.
 

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Discussion Starter #10
Wow, that very helpful. I wish I knew what the stock amps pushed. I will see if is in my FSM
 

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Discussion Starter #11
I moved this over from Classifieds so I would mess up his post :

Yes, this will work with the stock system. It has it's own built-in 100 watt amplifier so you don't have to rely on the stock amp. I'm currently running the stock '99 Bose stereo with this 10" Bazooka added on.

This would definitely add some bass to your stock setup, but i think it's going to really overpower your system since you'll be running 4 Ohm speakers (only ~12watts per speaker). Until you get your system fixed and putting out decent sound, this bazooka will be overkill.

Since you said you only have $200 to spend on your stereo, i'd recommend you replace your blown speakers first, then worry about getting more bass. No sense in having a lot of boom if you can't even make out the rest of the music.

You might be better off buying a non-amplified Bazooka (or other dual voice-coil sub) and powering it off the stock amp. It won't have nearly as much wattage, but it'll be cheaper and will have less of a chance of overpowering your current system. Then you can buy a bigger amp later if you want more volume.



If I go back to all stock and use the Bazooka it will over power my system ? How much is a non powered one ? And where can I get one ? Do I just run the wire up to one of the amps ??

Thanks again ...
 

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Dang on a 2bill budget I'd just buy some decent rear fill speakers. Power the front stage components off one stock amp, power the rears off the head unit and bridge the second amp to a 10DVC sub set up for 2ohm load. I don't know if the those little amps can hang. Many years ago, I bought one of RF punch40 for 40bucks off a coworker. That little thing was amazing I don't think fosgate puts the same quality in their products because they sell them everywere so they must have sent the construction overseas with cheaper parts.

My back speakers blew really quick. I listen to variety of tunes but I think my jungle, trance, D&B, electronica etc. has insane synthetic overlapping bass notes that can be torture on speakers. I found some oversized 6.5" at an overgoods electronic wherehouse for 12 bucks each. I bought them because the construction looked awsome and they are made by a company called Peerless out of Denmark. Peerless makes drivers for really nice homeaudio stuff but they just put a different tag on them. I did a little homework and these are car audio speakers. Dynaudio does the same thing but a different company. Most really nice car audio speaker are made out there in europe and you can find some sleeper speakers if you know were to look. I've got a set of 98' Diamond Audio hex three ways (not installed yet) but those were made in Germany by a bunch of ex-mb quart designers who wanted to make a higher quality speakers but now I think they are made in China now too. I mounted an a pair of old JBL GTi tweeters with the peerless drivers and they spank the crap out of the factory Clarions. But I'm taking them out once I put in the Hex's.
 

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Discussion Starter #13
THanks G. I think my speaker in the bacl blew becuase like you I listed to House music one minute then trance then Sinatra then Timbaland.

I need gues maybe I' hope someone has an extra decent amp sitting around they want to donate to me and buy some decent back speakers too. The ohms shit is driving me nuts. I just want to listen to Prodigy on the way home from work ...lol
 

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simple solution...for ~$200 this is what i would do

get one of these http://www.sounddomain.com/sku/USAUSX4065 ~$130
then get a set of these http://www.sounddomain.com/sku/BLAPCCI650
or these http://www.sounddomain.com/sku/ULTTC650
for the front stage, i'd got for the second set(the ultimate's, better SQ), then put your kenwoods in the rear and be done with it. of course, you gotta get a amp kit(rca's, power wire,etc.) so lets say under $275 for everything installed yourself...

later if you want to add a little boom in it, run the rear speakers directly off the Rockford HU and then bridge the rear channels on the amp into mono for the sub. this should be plenty of juice.

remember, this is what i would do...i'm not telling you this is final lol

also here's some word of advice..."you are only as strong as your weakest link" in which case i feel your amp is the weak link here, my advice to everyone, the first piece of car audio equipment you should upgrade(if you want) is your amp, its the backbone of your system...your stock amp is a weak 2 ohm amp obviously and its making your mind boggle if with a lot of nonsense setups i would never even think of doing...keep it plain and simple...that way, your "doing it right the first time" rememeber, all i've said is strictly opinionated...good luck :)
 

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Discussion Starter #15
Man, thanks again. you said I would need an amp kit. Is this becuase the wire I have running now are not compatible ?

I think I have a much clearer direction of this whole thing thanks everybody for your help. I will be back to bother you guys later I am sure:cheeky:
 

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I would generally agree that the amp should be the first thing that gets upgraded. But in this case, the problem seems to be that his speakers are blown (he stated in his original post that one of the speakers was rattling).

So, the first priority here is speakers to replace the blown rears. Now, he could buy a cheap set of speakers, then have enough money left over for a cheap amp, but i think he'd be better off sticking with the stock amp for now and buying better speakers. Also, because he's going to have to splice the new amp into the high-level inputs, i think the sound quality will be not too hot.

Of course, i don't think he's shooting very high for his SQ/SPL requirements, so maybe a cheap amp would do the job. Maybe he could split the difference and buy a set of decent speakers for the rear (maybe even a set of separates) and a used ~200w 2/4ch amp (2ch with a bridgable channel would be great).

I also had a Punch 45 long ago. That amp just rocked. I had it running two door speakers and a 12" Rockford sub and it just pumped out the power. Their old stuff was great. Not too sure about their newer amps/subs.
 

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poppy_morenito said:
Man, thanks again. you said I would need an amp kit. Is this becuase the wire I have running now are not compatible ?

I think I have a much clearer direction of this whole thing thanks everybody for your help. I will be back to bother you guys later I am sure:cheeky:
usually when installing an aftermarket amp, you'll need some thicker power wire, an inline fuse, some ground wire, a set of RCA's, a remote turn-on wire and a buncha little connectors, crimps and whatnot. an amp kit should include all or most of these. you should also shop around and see if you can find a pro to install it, if you dont feel confident. that way you can always take it back to them if something goes wrong.

but the complete easiest cheapest route,(last option i've giving you lol) get an inexpensive set of (4 ohm) components for the fronts, and put the kenwood's in the rear and bypass your stock amp completely and run straight HU power (no external amps) run wire directly from the rockford HU to your speakers. should sound nice and clean. should cost about ~$100, if you get a set of the Ultimate components, some speaker wire and a little time, good luck.
 

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Cue-Ball said:
I would generally agree that the amp should be the first thing that gets upgraded. But in this case, the problem seems to be that his speakers are blown (he stated in his original post that one of the speakers was rattling).

So, the first priority here is speakers to replace the blown rears. Now, he could buy a cheap set of speakers, then have enough money left over for a cheap amp, but i think he'd be better off sticking with the stock amp for now and buying better speakers. Also, because he's going to have to splice the new amp into the high-level inputs, i think the sound quality will be not too hot.

Of course, i don't think he's shooting very high for his SQ/SPL requirements, so maybe a cheap amp would do the job. Maybe he could split the difference and buy a set of decent speakers for the rear (maybe even a set of separates) and a used ~200w 2/4ch amp (2ch with a bridgable channel would be great).

I also had a Punch 45 long ago. That amp just rocked. I had it running two door speakers and a 12" Rockford sub and it just pumped out the power. Their old stuff was great. Not too sure about their newer amps/subs.
you gotta remember, he does have an aftermarket deck already that has 4.5v pre-outs, and it has power 40x4 if i'm not mistaken...so theirs no need to splice anything, run straight rca's from the back of the deck directly to the amp, if he decides to get an amp...but then again, he doesn't even need an amp at all, just run straight deck power and bypass the stock amp completely. i dont know, but what ever you decide let us know :)
 

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Discussion Starter #19
Is there a way I can just turn off the amp and have the power from my HU go straight my speakers ?

Will I have to pull abunch of wire to do this ? How will I get the speaker wires to run directly into unit ?

Long story :

I used to have a crappy no name HU in first car ( mazda glc rip) that had no amp at all. I bought at one of those places where they ask how much yo got to spend today places. It said it was 50 watts per channel.

I installed it and two hours later ( becuase I had no idea where the wiring was going becuase the directions where in Korean ). I actually had sound to my stock speakers but they sounded like crap but better crap than I had.

I used to work for PageNet, the beeper company and one one my resellers sold car audio stuff. I asked him to take a look at my setup. After he finished laughing at my car. ( it still hade those dancing greatfull dead bears stickers all over it ) He said he would make me a deal if I knocked $100 off his bill he would get me new speakers. I used to look at peakers prices out of JC Whitney so I though that price was outrageus ...lol

I said are they at least Pioneer. He said no " better " . He put these " no - name " speakers in and BAM the car was rocking !!!!

Flash foward 2 years later, I am trading in ...lol my my 1983 Mazda GlC with 214,000 on it for a 1991 Celica the dealer offers me $500 for the car. I paid $800 for it so I am happy.

The first thing they do is rip out my stereo and speakers and a tow truck takes my car. The manger told me he did not give s shit aout my car, he was donating to his son's HS shop class. He bought my HU and and Infinity Kappa speakers....to intall in another car ...lol:

I know it can be done .....

Thanks again you guys.. you are like car genius' I never really cared unitl now ... Active Directory in Win2k is easier than this ....
 
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