safe having 6 speakers?

hey guys, i wanna know, with the 3rd gen integra's my friend bought a new HU and he wants to add 2 more speakers on the rear deck, near the passengers head at the rear. he plans of cutting the stock deck or replacing it and making a new deck for 2 6x9's. and he doesnt want a amp. could he just connect it to the wires which are being used by the rear speakers. cant the current rears share the wiring with the 2 new additional speakers. and woudl it matter what wattage the speakers are. he will change the stock speakers at the rear and add the 2 new ones at the rear deck.

and will the soudn quality be crappy, he doesnt make the volume og full blast anyway.

thanks

Your head unit isnt designed to operate two sets of speakers like that. I would recomend getting an amp to operate 3 sets of speakers.

just buy two good speakers, i think its looks stupid to have an extra set of speakers on the rear deck if the car still isnt loud.the speakers would not be getting the correct watts and you could burn the speaker outputs on the radio.Change the factory speakers to some decent speakers and thats it. peace.

yea, just get a amp, and it should work even better.