Tweeter resistance

[mkafridi]

Hi all!

I have Carrozzeria TS-V017A tweeters which have stated 4 OHM on it. But my multi-meter shows a resistance of 10 OHM. I don't have a crossover for them so will any car audio crossover made for 4 OHM tweeter work with it of do I have to make a custom crossover?

An externally hosted image should be here but it was not working when we last tested it.

 

[picowallspeaker]

Z differs from Re
DC Re as seen by a multimeter will be lower than real Z
Probably those tweeters have a hidden internal resistor to limit over-abuse

 

[JonSnell Electronic]

The crossover will be a single 4u7 capacitor. Usually Bi Polar Electrolytic at 25V or more.

 

[picowallspeaker]

Hi Jon, for tweeters the Dt/Dv rating of the cap( which I don't know the meaning very well, but...) is important so the higher the voltage the better.
250 V is a standard ( thou I may use 63V or 100 V ...)

 

[mkafridi]

The crossover will be a single 4u7 capacitor. Usually Bi Polar Electrolytic at 25V or more.

So I can not use my Diamond audio hex S6.0S crossovers with these tweeters??

 

[giralfino]

I have Carrozzeria TS-V017A tweeters which have stated 4 OHM on it. But my multi-meter shows a resistance of 10 OHM.

This is strange. Usually a driver with a nominal impedance of 4 Ohm should have a coil resistance between 3 and 4 Ohm (Re). One possibility is that your meter is way off so try measuring a known resistor of a similar value (e.g. 3R3 or 3R9 resistors), and compare the measured vs nominal value.
Another possibility is that the tweeters have some internal resistance added, or that they are indeed 12-16 Ohm of nominal impedance (unlikely). Either way a car crossover designed for 4 Ohm won't work with these.

Ralf

Judging on the images I've seen on the net, the specific crossover could have a film cap and a coil in the tweeter part.

 

[mkafridi]

Help needed to recreate this crossover:

An externally hosted image should be here but it was not working when we last tested it.

 

[mkafridi]

Hi Jon, for tweeters the Dt/Dv rating of the cap( which I don't know the meaning very well, but...) is important so the higher the voltage the better.
250 V is a standard ( thou I may use 63V or 100 V ...)

This is strange. Usually a driver with a nominal impedance of 4 Ohm should have a coil resistance between 3 and 4 Ohm (Re). One possibility is that your meter is way off so try measuring a known resistor of a similar value (e.g. 3R3 or 3R9 resistors), and compare the measured vs nominal value.
Another possibility is that the tweeters have some internal resistance added, or that they are indeed 12-16 Ohm of nominal impedance (unlikely). Either way a car crossover designed for 4 Ohm won't work with these.

Ralf

Judging on the images I've seen on the net, the specific crossover could have a film cap and a coil in the tweeter part.

The crossover will be a single 4u7 capacitor. Usually Bi Polar Electrolytic at 25V or more.

I want to know the circuit diagram which I want to recreate...
I know from the the ratings on caps:
Big round Cap: 15 micro Farad
Square Cap Left: 2.7 micro Farad
Square Cap Right: 3.3 micro Farad

Right and Mid resister: 5.6K ohm

The Left resister is for the switch so not needed: 3.3K ohm

I do not know the values of the coils or how the circuit is connected!
Please provide me a circuit diagram so that I can run my tweeters...

 

[mkafridi]

Caps I will buy are:
2pcs Bennic MT 100V3 3uF 335J Axially Dividing Metalized Film Capacitors | eBay
2pcs JBL Customized Bennic 100V2 7uF Axial Division Capacitors MEF | eBay
2pcs for Bennic 100V 15uF Audio Speaker Divider Crossover Non Polarity Capacitor | eBay