Speaker impedance

[zega55]

Hi people
I have a question and it goes like this
If I add a resistor in series with tweeter will I change his impedance (for crossover design)?

[janneman]

Originally posted by zega55
Hi people
I have a question and it goes like this
If I add a resistor in series with tweeter will I change his impedance (for crossover design)?

Yes, of course.
Now, if you want to attenuate the tweeter without changing the load for the xover, you need a two-resistor attenuator that gives the required attenuation, while keeping the resulting load the same.
What is the tweeter impedance, and how much do you want to attenuate it?

Jan Didden

[zega55]

I wanted know was I righ by saying that the load changes. Some people told me that I was wrong and it got me thinking so I asked. If I add a 2ohm resistor in series with tweeter his impedance will then be 8ohm. DC resistance of the voice coil is 4,8ohm (so it is a 6ohm speaker).
The midwoofer is 90db and tweeter is 91db so the attenuation of 1db is ok?
Thank you for your help.

sorry for my english I dont use it often

[janneman]

Originally posted by zega55
I wanted know was I righ by saying that the load changes. Some people told me that I was wrong and it got me thinking so I asked. If I add a 2ohm resistor in series with tweeter his impedance will then be 8ohm. DC resistance of the voice coil is 4,8ohm (so it is a 6ohm speaker).
The midwoofer is 90db and tweeter is 91db so the attenuation of 1db is ok?
Thank you for your help.

sorry for my english I dont use it often

Your attenuation is: 20 log (6ohms/2+6 ohms) = about -2.5dB in voltage.

Jan Didden

[zega55]

Originally posted by janneman



Your attenuation is: 20 log (6ohms/2+6 ohms) = about -2.5dB in voltage.

Jan Didden

this is a formula by wich it is calculated? That 2 in formula is the resistor I added in series with tweeter?
So if I add a 1ohm it will be:

20 log (6/1+6)= about -1.34db and will the tweeter impedance then be 8 ohm? Is their a formula for that?