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Old 12-27-2001, 06:58 PM Thread Starter
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Someone explain Ohms to me...

What should I look for when buying subs? 2ohm, 4 ohm, 8 ohm?
What is the differance?
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Old 12-27-2001, 07:35 PM
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ohms

Ohms means resistance.
On a sub the higher the resistance the better quality sound, thus 8 ohms is high quality but you need major amperage to run them, 4 ohms does well for most people and alot of people that are just looking for thump goto 2 ohms or even 1-ohms.

If you want more info pm slow90vert, he does car audio stuff so he knows more than me
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Old 12-27-2001, 09:09 PM
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Ohms is a measure of resistance,

but an just because a speaker is rated at 8 ohms, does not mean it will sound better than a 4 ohm speaker.

I think what you are reffering to is:

when an amplifier is bridged or is run into a lower impedance you lose some dynamic range

this is really not important in the lower frequences of a sub


As for the orginal question,

You should pick your subs Ohms base on the number of subs you want to run and the capabilities of your amp.

Most amps are 2ohm stable.

If you are going to bridge a 2 channel amp, and run a pair of subs, I reccomend 8ohm subs wired in parallel.
Wiring the subs + to+ and - to- will give you a 4 ohm load.
Any bridged amp wil "see" half the load you put on it, hence 2 ohm load.

If you are going to one run one sub and a 2 channel amp, get a 4 ohm sub.

If you are going to run a mono amp, mutipule subs, etc...
E-mail me

James
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Old 12-27-2001, 11:04 PM
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I cant say anything these guys said.

Its just resistance.

Say you have an amp that pushes 500w at 4 ohms.
Put a dvc 4 ohm speaker on that amp (wich lowers resistance by 1/2) so the amp can make more power with less resistance.

Ex: My rockford BD1000.1 is rated at 500w at 4 ohms.
With a dvc 4 ohm solobaric, the amp is putting over 1100w out.
Just make sure your amp is 1-2 ohm sable or youll burn that bitch up!
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Old 12-28-2001, 01:35 PM Thread Starter
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So, I should just get 8 ohm subs?

I am planning on running 2 10" subs. Not sure about the amp yet. But, I want more power than I have now.

Profile 400sx with 2 Rockford Fosgate 10" 100w subs(I think they are 4 ohms).
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Old 12-28-2001, 01:53 PM
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Run 2 8ohm subs wired in series to drop the resistance to 4ohm. Find an amp rated for equal max of the subs at 4ohm mono bridged. Even though some manufacturers rate their amps 2ohm stable they heat up very quick and shut off. Been there done that.
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Old 12-28-2001, 02:02 PM Thread Starter
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Thanks Oxidizer. Any deals on the N20 kit yet?
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Old 12-28-2001, 02:24 PM
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They are taking orders on them now. I have talked to Mike Wilson at DMP already and he said he would take care of anybody I refer to him. They usually sell their stuff less than Summit and Jeg's.
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Old 12-28-2001, 08:51 PM
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Quote:
Originally posted by Oxidizer187
Run 2 8ohm subs wired in series to drop the resistance to 4ohm. Find an amp rated for equal max of the subs at 4ohm mono bridged. Even though some manufacturers rate their amps 2ohm stable they heat up very quick and shut off. Been there done that.
If you series wire two 8 ohm subs you will get a 16 ohm load.

Remember, when you bridge an amp it will "see" half the load you put on it. So, if you paralell two 8 ohm subs (equals 4 ohms), then put this load on a bridged amp, the amp will "see" a 2 ohm load.

n737nc,

I would base what impedance subs you buy, on which amp you have or will have for the subs.

What is nice, bass is very forgiving, it is not nescessary to spend $$$$, it is more important that you match your amp, subs and enclosure (capabilities not brand).

James
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Old 12-29-2001, 11:40 AM
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James is correct and most amps are not 2 ohm mono stable.
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Old 12-29-2001, 04:52 PM
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Ok, say i was to get my hands on two jl audio 10w6's. In your guys' opinions, what amp and enclosure would run them the best for a 92 hatchback? 2 or 4 ohm.
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Old 12-29-2001, 10:14 PM
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Quote:
Originally posted by stangcrazy
Ok, say i was to get my hands on two jl audio 10w6's. In your guys' opinions, what amp and enclosure would run them the best for a 92 hatchback? 2 or 4 ohm.
stangcrazy,

One of the great things about a hatchback, is that it will be 3 to 6 db (2 to 4 times) louder than a sedan.

I would go with a sealed box, it will give you the tightest most accurate bass in the smallest and lightest box. A sealed box will require more power than ported or bandpass.

Of course if you are not concerned about space or weight you could go with a ported box and get even more output.

W6's are dual 6 ohm subs. They are also a little power-hungry.

If I were running two of them:

On a 2 channel amp, I would wire the voice coils on each sub in series to get a 12 ohm load, then wire the subs in parallel to get a 6 ohm load. The bridged amp will "see" a 3 ohm load.
(Kicker ZR600, PG XS2500, RF 800.2 etc...)

On a 4 channel amp, I would wire the voice coils on each sub in parallel to get a 3 ohm load, then bridge the amp to a two channel and run one sub off of each channel.
(Kicker ZX460, PG ZX475, RF 800.4 etc...)

On a mono amp, I would wire the voice coils on each sub in parallel to get a 3 ohm load, then wire the subs in parallel to get a 1.5 ohm load.
(Kicker DX 700, RF BD1000, JL mono amp not sure of model #)


James
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Old 12-30-2001, 08:19 AM
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wow, reminds me of my radio shack days...ah, nice to be making real money now

"Jesus has my heart, but Whiskey has my liver" --Jason Boland
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Old 12-30-2001, 08:26 AM
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Quote:
Originally posted by blacksn95
wow, reminds me of my radio shack days...ah, nice to be making real money now
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Old 12-30-2001, 08:51 AM
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thanks 89lx5.0

Thanks 89lx5.0,

you helped alot, hope you're willing to answer anymore questions I might have
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Old 12-30-2001, 08:59 AM
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Re: thanks 89lx5.0

Quote:
Originally posted by stangcrazy
Thanks 89lx5.0,

you helped alot, hope you're willing to answer anymore questions I might have
Sure thing stangcrazy, glad to help.

James
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Old 12-30-2001, 09:24 AM
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help with the wiring

Ok, lets say i wanted to use the 2-channel amp method. tell me if this is right. if it's wrong post a pic of the right one will ya? Thanks
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Old 12-30-2001, 09:27 AM
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Damn the attachment wont show. If you have a pic or can draw up a schematic of the wiring, please post it based on 89lx5.0's 2-channel method
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Old 12-30-2001, 11:33 PM
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Quote:
Originally posted by 89lx5.0


I remember explaining ohm's law/resistance almost daily when I worked there. Now I just watch movies on the internet .
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Old 01-01-2002, 12:02 PM
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Old 01-02-2002, 03:28 PM
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That is not 100 percent right

Quote:
Originally posted by 89lx5.0


If you series wire two 8 ohm subs you will get a 16 ohm load.

Remember, when you bridge an amp it will "see" half the load you put on it. So, if you paralell two 8 ohm subs (equals 4 ohms), then put this load on a bridged amp, the amp will "see" a 2 ohm load.

n737nc,

I would base what impedance subs you buy, on which amp you have or will have for the subs.

What is nice, bass is very forgiving, it is not nescessary to spend $$$$, it is more important that you match your amp, subs and enclosure (capabilities not brand).

James
I agree with the 16 ohms and the 4 ohm scenario you are talking about. But the amp sees the load you present it. If you hook it up to a 4 ohm speaker it sees 4 ohms. Thus if you hook it up to two 8 ohms wired in parallel which is 4 ohms, the amp still sees 4 ohms. When you bridge an amp all you are doing is combining the stereo channels to make 1 channel. You are correct in saying that most amps are only 2 ohm stereo stable which would make them 4 ohm mono stable. Just my .02 cents worth.
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Old 01-02-2002, 04:37 PM
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Quote:
Originally posted by FunFordCobra
(SMACK!)
You think so?

I thought so to, but then I said to myself,

I said "Self, surely someone would not come to this forum talking shit, cetianly not when all I am trying to do is help someone else."

But, what the hell, maybe it is "SMACK!", wouldn't know, don't normally talk shit.

James
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Old 01-02-2002, 04:44 PM
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Re: That is not 100 percent right

Quote:
Originally posted by MUSTANG MAN


I agree with the 16 ohms and the 4 ohm scenario you are talking about. But the amp sees the load you present it. If you hook it up to a 4 ohm speaker it sees 4 ohms. Thus if you hook it up to two 8 ohms wired in parallel which is 4 ohms, the amp still sees 4 ohms. When you bridge an amp all you are doing is combining the stereo channels to make 1 channel. You are correct in saying that most amps are only 2 ohm stereo stable which would make them 4 ohm mono stable. Just my .02 cents worth.
I see your point, but understand I was just trying to explain this in a way that everyone can understand.

I still say that the easiest way to do that is say...a BRIDGED amp will "see" half the load presented to it.

That is why the stereo ohm rating is lower than the bridged rating.

James
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Old 01-02-2002, 06:04 PM
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Re: Re: That is not 100 percent right

Quote:
Originally posted by 89lx5.0


I see your point, but understand I was just trying to explain this in a way that everyone can understand.

I still say that the easiest way to do that is say...a BRIDGED amp will "see" half the load presented to it.

That is why the stereo ohm rating is lower than the bridged rating.

James
I am glad you see my point I am just trying to keep someone else from frying their equipment. I have been doing stereo installs for 10 years now and have seen a lot of people fry their shit because someone confused the living hell out of them.
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Old 01-04-2002, 10:58 AM
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this is the longest thread I have ever seen in this forum!
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