All head units that I know say that each channel is rated at 4 ohms, almost every single infinity speaker that is made is rated at 2 ohms. Is it possible to put an infinity speaker such as Infinity Kappa 63.9i on each channel of a head unit? My friend wants to upgrade his car speakers and go with these so I wanted to know if its safe and what Infinity says is true?

True Four Ohms— All Kappa speakers feature two ohm voice coils. Original factory-installed speaker wiring in many cars is 18-22 gauge. This wire, and heating in the voice coil when power is applied, increase the impedance “seen” by the amplifier or head unit. The impedance of Kappa Speakers has been adjusted to compensate for this increase and can be safely driven by any head unit.

http://www.infinitysystems.com/car/products/product_detail.aspx?prod=KAPPA63.9I&cat=KAP&ser=KAP&Language=ENG&Country=US&Region=USA

thanks for input.

Crutchfield says this about the product (just want someone to agree if I should do it or dont because I dont want to mess up a headunit):

SLI High-Output Design: This high output 2 ohm design extracts every watt from today's high powered receivers and amplifiers, increasing overall system output and efficiency (relative to 4 ohm speakers).

Important Note: These Infinity speakers use a low impedance design to pull more power safely from your car stereo or amplifier. This design is compatible with all factory and aftermarket stereos.

i had my infinity kappa tweeters running off the h/u and they just clipped the sh!t out of them at like half volume ... they also shut down the h/u's internal amp very quickly with eq set to flat no loudness and sla on lowest setting