What does Re: mean in ohm ratings? Please read

[ckunke002 10+ year member]

I've noticed this in a few different places, and I'm on sundown's website right now.

On the SA-12 subs, the specs look like this.

D2 Model :

Re: 4.57 ohms

D4 Model :

Re: 7.07 ohms

This doesn't make any logical sense. I thought Ohms were only 1 whole number.. like 2 or 4 and such. Other website say that the D2 is 2 ohm dual coils and the d4 is 4 ohm, so why does the website say 4.57 and 7.07?

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[ahole-ic]

I've noticed this in a few different places, and I'm on sundown's website right now.
On the SA-12 subs, the specs look like this.

D2 Model :

Re: 4.57 ohms

D4 Model :

Re: 7.07 ohms

This doesn't make any logical sense. I thought Ohms were only 1 whole number.. like 2 or 4 and such. Other website say that the D2 is 2 ohm dual coils and the d4 is 4 ohm, so why does the website say 4.57 and 7.07?

LOL. No. That is the resistance of the coil at rest in the gap. You are concerned with the impedence while at rest in the gap. Resistance and impedence do not have to be whole numbers. In fact if you were to accurately measure impedence (you can't. You don't have the proper tools to do so) you would see your coils are not dead on.

 

[THATpurpleKUSH 5,000+ posts]

ITs because the subs have dual voice coils and they are usually wired in series for thiele small parameters. Divide those #s in half to get the reading for each coil.

Voice coils almost never are a whole number. They will be a little more or a little less than what their nominal rating is, as you see above.

 

[ckunke002 10+ year member]

LOL. No. That is the resistance of the coil at rest in the gap. You are concerned with the impedence while at rest in the gap. Resistance and impedence do not have to be whole numbers. In fact if you were to accurately measure impedence (you can't. You don't have the proper tools to do so) you would see your coils are not dead on.

Ok.. so if I were to buy one of these and hook it up as a normal dual voice coil 2 or 4 ohm (depending on d2 or d4) everything would be fine?

And why do they even give that info but not the normal impedance? I've also noticed this on many of these companies websites

 

[ahole-ic]

Ok.. so if I were to buy one of these and hook it up as a normal dual voice coil 2 or 4 ohm (depending on d2 or d4) everything would be fine?
And why do they even give that info but not the normal impedance? I've also noticed this on many of these companies websites

The nominal is given when they say dual 2 or dual 4. You don't need to be any more precise than that. They give this out so when retards hook up their dmm's and read the coils and throw a fit they can refer them back to the specs.... since all of the "car audio experts" have no idea that there is a difference between impedence and resistance.

 

[Falcons 5,000+ posts]

in general i wouldnt even worry about this. unless if you want to know car audio inside and out, and know all of the science and math about it, then just look at the rms, the coil impedance, and your golden.

 

[ckunke002 10+ year member]

The nominal is given when they say dual 2 or dual 4. You don't need to be any more precise than that. They give this out so when retards hook up their dmm's and read the coils and throw a fit they can refer them back to the specs.... since all of the "car audio experts" have no idea that there is a difference between impedence and resistance.

in general i wouldnt even worry about this. unless if you want to know car audio inside and out, and know all of the science and math about it, then just look at the rms, the coil impedance, and your golden.

Perfect.. thanks yall