Home Theater Forum and Systems banner

1 - 14 of 14 Posts

·
Registered
Joined
·
68 Posts
Discussion Starter · #1 ·
Ok, well ohms law didnt really fail but I have a pair of car audio component speakers that are 4 ohm each.

I wired the crossover input wires in parallel and got a 2 ohm load. When I wire it in series, it is still 4 ohm, not 8 ohm...

Any help?
 

·
Registered
Joined
·
68 Posts
Discussion Starter · #3 ·
with a multimeter set to 200 ohms range

each comp separately was 4.3 ohms
series was 4.6 ohms
parallel was 2.3 ohms
 

·
Registered
Joined
·
58 Posts
You are reading DCR ( DC resistance ) not impedance.
This is a common mistake.
AC and impedance involve the addition variables of frequency and phase.
DC resistance is commonly 60 - 80% of impedance.
But speakers are reactive elements, so their impedance varies with frequency.
Often impedance values are stated at a given standard frequency of 1000Hz.

Syd
 

·
Registered
Joined
·
68 Posts
Discussion Starter · #5 ·
But how come when I measure my subs in DC, it reads like normal?
And how could I measure actual impedance?
 

·
Registered
Joined
·
68 Posts
Discussion Starter · #7 ·
So, can I just hook up the speakers to my receiver and play a certain sine frequency and then measure the ohms? or will that somehow mess up the receiver?
 

·
Plain ole user
Joined
·
11,121 Posts
The resistive component should still add. You are either not wiring in series like you think or you are measuring at the wrong points. You may also have a load in the crossover altering your reading.
 

·
Registered
Joined
·
68 Posts
Discussion Starter · #9 ·
both crossovers have tweets and mids attached to them and I wired them + +- - and tested ohms on the left + and right -

They do add, they increase by .3 ohms...
 

·
Registered
Joined
·
68 Posts
Discussion Starter · #11 ·
When I just do the mids or tweets, I get a higher "correct" reading.

Now what do I do about the two crossovers?
 

·
Registered
Joined
·
68 Posts
Discussion Starter · #12 ·
Can I wire both mids and tweets through one cross over? Will the cross be able to handle the power?
 

·
Registered
Joined
·
2,625 Posts
Ok, well ohms law didnt really fail but I have a pair of car audio component speakers that are 4 ohm each.

I wired the crossover input wires in parallel and got a 2 ohm load. When I wire it in series, it is still 4 ohm, not 8 ohm...

Any help?
Wouldn't you only have one crossover input wire per output?

I'm not a car audio guy, but the crossover simply distributes the correct frequency range to the speaker components. This is almost always done in parallel. But you only get a parallel load if you have dual drivers on one of the frequency ranges.
 

·
Registered
Joined
·
14 Posts
So, can I just hook up the speakers to my receiver and play a certain sine frequency and then measure the ohms? or will that somehow mess up the receiver?
No, never do that, you'll probably bust your receiver or give it a very very hard time of it's life :eek:lddude:...
Try using speaker workshop, it measure impedance using your sound card's line in/out and a ref resistor
 
1 - 14 of 14 Posts
Top