I am looking for outdoor speakers to be powered by the "B" switch of my Onkyo receiver 595. I am leaning towards the NHT Outdoor Ones which I can get for about $230 a pair. I like the 6" woofer on these. The issue is the nominal impedance. See this (from Crutchfield): Key Features: customized mounting bracket and isolation base frequency response 57-21,000 Hz (±3dB) 6-ohm impedance sensitivity 88 dB each handles up to 150 watts black or white finish 11-3/4"H x 7-5/16"W x 7-1/2"D warranty: 5 years Although the NHT website says 8 ohm impedance. Does this 6 or 8 impedance matter? ALL of the other speakers in this category (Polk Atrium, Klipsch SA-1, Boston Acoustics Voyager Pro) are at 8 ohm. Bottom line, is this an issue? THANKS.