fi coil reading?

[Nikitaaa]

If I wanted to get to a final coil impedance of. 33 with two subs, what impedance would I need?

[Nikitaaa]

Or.35 I think? So I would need the dual 2's right? Assuming everything is wired in parallel

[Katt]

D1 = .7, D2 = 1.4. Wire both down to .7 then down to .35. So yeah, "D2".

[cloud77]

a.66 in paralell

[Nikitaaa]

So just to clarify, I would need the 1.4?

[bkolfo4]

They are dual 1 and dual 2, not .7 and 1.4.

.7 and 1.4 is the DC Resistance. You are NOT going to be applying DC voltage to the speaker.

If you want a 1/2 ohm load, get D2 and wire all 4 coils in parallel. That will be 0.5 ohms nominal. Be prepared - it will be MUCH higher around Fs, but it does not matter

[Nikitaaa]

They are dual 1 and dual 2, not .7 and 1.4.

.7 and 1.4 is the DC Resistance. You are NOT going to be applying DC voltage to the speaker.

If you want a 1/2 ohm load, get D2 and wire all 4 coils in parallel. That will be 0.5 ohms nominal. Be prepared - it will be MUCH higher around Fs, but it does not matter

Wait I'm confused.. are you saying I'll actually be seeing half ohm even if could read 1.4 each?

[bkolfo4]

You are measuring with a meter that can only measure DC resistance. DC resistance is like a car battery or a 9 volt battery, AA battery, etc.

If you applied a 9 volt battery to you sub coil, the cone would to position X and sit there. This is the type of resistance your meter will measure.

Your meter will not measure AC impedance. Impedance is the "resistance" of the coil when an AC voltage is applied. AC is like a test tone or music - the voltage alternates between positive and negative at some frequency X (a wall socket is an AC voltage of 120 volts at 60 Hz). Impedance varies with frequency for multiple reasons. The two main reasons for a sub are 1. The resonant frequency of the moving assembly, and 2. The natural low pass filter effect of the coil acting like an inductor.

When the sub is rated "2 ohms nominal", this is like an average impedance over the usable bandwith a couple of other considerations on how low the impedance is at the lowest point (it will never be lower than the DC resistance).

A big issue people have is the BIG spike at Fs (and it is not just at that frequency - it is liek a bell curve if you plot it). People 90% of the time have no idea the spike is even there and call it "impedance rise" thinking it is occurring due to the sub being placed in a box. They have no idea it would still be there if the sub was out of the box sitting on a table. A lot of the subs we use in the car have an Fs around 30-35 Hz, which creates a much higher impedance in the frequency range we like to use them. That is why you constantly see people clamping the output from their amps and then they say "I got X watts rising to Y ohms". It really is not "rising" like they think, that is just the impedance of the sub at that frequency.

The good thing is that this spike does not matter for playing music. I repeat - it DOES NOT MATTER. The sub still plays just as loud at Fs as it does where the impedance is at a minimum. If you really want to know what is going on with your amp and sub, you would need to clamp at each frequency in the usable range.

And one final thing on impedance - 95% of power to a sub turns to heat. Coils get very hot. Resistance and Impedance increases once you are playing the sub for a couple of minutes. . .

[skittlesRgood]

I just want to be the responsible one and point out that if you're this confused about how to wire a sub, you shouldn't be wiring so low. yes, I know you wont listen but you really should wait until you get a little more experience.

You also have to understand that if you fry your amp then it was your fault. don't bitch at the company or expect them to warranty the amp.

[Nikitaaa]

I just want to be the responsible one and point out that if you're this confused about how to wire a sub, you shouldn't be wiring so low. yes, I know you wont listen but you really should wait until you get a little more experience.

You also have to understand that if you fry your amp then it was your fault. don't bitch at the company or expect them to warranty the amp.

I appreciate your concern but I'll take my chances with this one. I've wired to a quater daily in the past and when I did that I picked up a few tips to keep my impedance up to a healthy amount to keep the amp protect free.

I completely understand that if anything blows, it will be my fault and my fault only.

I was just unfamiliar with fi's coils reading different than stated on the website and wanted some insight from someone who had more knowledge on the specific equipment.