Do ohms have any relation to SQ?

Ex. If I have a D2ohm sub that requires 500w rms and two different amps. 1 puts 500w rms at 1ohm and the other does 500w rms at 4ohm. Is the 4ohm one going to be better SQ wise. Just curious because a friend told me while lower ohms is less resistance that higher ohms is better for SQ. Thanks for any input

 

An amp will not drive as cleanly into a lower load. Meaning as resistance (ohms), goes down THD (distortion) goes up.

The elevated distortion levels will be more audible (theoretically) through your components than with a subwoofer. That's why you more often see people running subs at 1 or 2 ohms, but not very often do you see people running their mids/highs at 1 or 2 ohms. (It's also the reason a traditional class D amp is ok to use on a sub, but is not typically recommended for your mids/highs)

In your example above with a subwoofer, I wouldn't worry about the SQ difference because THD is inaudible to the human ear in the frequencies a subwoofer is playing (below ~100Hz)

Is this audible to your ears in a noisy car at 65mph were the noise floor is already very high? That is for you to decide, but I doubt it.