1 ohm = 'dirty signal'?

[n2audio 5,000+ posts]

its more efficeint to run at 1 ohm then 4 ohm

That's a generalization that isn't true in every case.

 

[helotaxi 5,000+ posts]

^^^ Actually that's untrue in every case. More current means more heat means less efficient. Every time.

May need to wire to 1 ohm to get the most power from the amp, but hte amp won't be it's most efficient at that impedance.