Amp question

[TheNerfsmith]

I found and will soon have one of the factory RX-172 head units. My question is if an amp would be required to run it along with the speakers I have to get at some point. I don’t know much about sound systems so I’m out of my element. 

[hgeranium]

I think it depends on the speakers you put in there, or especially if you put a subwoofer. My money is you probably don't need an amp if you're running modest (aka not huge loud powerful) speakers with a factory HU

[eaglescout526]

Factory speaker resistance is 8Ω ont he factory radios. 

[TheNerfsmith]

1 hour ago, eaglescout526 said:

Factory speaker resistance is 8Ω ont he factory radios. 

Does this mean I need to find speakers which match that resistance? Or is it scale of which 8 or under is preferred? 

[eaglescout526]

You can run lower impedance speakers just fine. But I’m just throwing factory spec out there.