I have an '06 MCS with the OEM stock HU, I was looking into replaceing the stock speakers, I decided on Infinity Kappa's 6.5" in the front and 6x9" in the rear.
But before I bought them I noticed they were 2Ohm and not 4Ohm.

What are the potential issues, I know it is going to make the HU work harder and may "fry" the HU due to overwork. But is there any other issues?
And how well do you think the HU will handle with the 2ohm speakers? or how long it will last?

My other option was going with the Infinity Reference speakers that are 4ohm, but the efficency is lower than the Kappas, so I would prefer to use the Kappas

P.S. As of right now I have no desire to change the HU. But it may be a possibility in the future.

Thanks,

Arty

 

I'd think frying the HU internal amplifier would be the biggest issue, it may work for a while, it may fry the head unit in a matter of days, it's hard to tell unless someone else has done that exact thing. I wouldn't run the 2ohm speakers unless you were prepared to put an amplifier that's 2ohm stable in to power them.

 

The 2 Ohm speaks will place a double load on the HU amp on each channel. This can damage the headunit amp, but most modern amplifier ICs have a thermal protection system that shuts down the circuitry if the chip overheats due to an overload. The circuit will also limit total output current in order to protect itself as well. You'll hear this as distortion as you turn the voume up, and noise or silence after a while as the overtemp protection kicks in. The Kappas are nice speakers, but they need an amp capable of powering them with their low impedance.