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Speaker impedance.

Njoy

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Jun 15, 2021
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Hello,
My first post here.I was just reading the review Of Edifier R1280T.This speaker uses a 6ohm woofer and 4 ohm tweeter.A 3.3 microfarad capacitor is used for the tweeter as high pass filter.Seeing pics of the internals, the speakers are connected in parallel with tweeter connected in reverse polarity to the amplifier.

My question is,does this parallel connection make the total impedance of the speaker 2.4 ohm.The class D chip used is TAS5713 as power amplifier.According to TI data sheet minimum impedance for the chip is 4ohm.
 

SIY

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Apr 6, 2018
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Hello,
My first post here.I was just reading the review Of Edifier R1280T.This speaker uses a 6ohm woofer and 4 ohm tweeter.A 3.3 microfarad capacitor is used for the tweeter as high pass filter.Seeing pics of the internals, the speakers are connected in parallel with tweeter connected in reverse polarity to the amplifier.

My question is,does this parallel connection make the total impedance of the speaker 2.4 ohm.The class D chip used is TAS5713 as power amplifier.According to TI data sheet minimum impedance for the chip is 4ohm.

That depends.

First, understand that the impedance numbers have little meaning. The impedance of a driver is not anything like constant with frequency, and a typical woofer might have an impedance that is as high as 40 ohms and as low as 3 ohms (to make it worse, the impedance is actually a complex number, with both resistance and reactance...). Usually, a woofer will show a rising impedance with frequency due to its voice coil inductance. So the impedance with the tweeter plus its series capacitor in parallel with the woofer is unlikely to be 2.4 ohms.

But unless you have the impedance data of each driver and model the system with its passive crossover, you can't say for sure what that impedance is likely to be.
 
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