the Amp produces distortion also that’s why you have to dd1 every item in the line when you use it... the dd1 is used to match the voltage from the deck so if it hits 2 volts and it produces the 1% distortion the light comes on.. and not seeing the 1k as long as it sees it before the distortion light comes on then it should be ok. I’m assuming..... my deck had 0 distortion with volume all the way up and with the sub out all the way up... but it’s also a 4 volt output