I have an Onkyo TX-SR508 amp and am investigating inexpensive bookshelf speakers. I've read good things about the ELAC DB 2.0 B 6.2 pair. They are rated at 6 ohms. The amp's manual says "90 watts/channel @ 8 ohms (FTC). 130 watts/channel @ 6 ohms (IEC). 160 watts/channel @ 6 ohms (JEITA)." Will these speakers be OK? Or should I look for something at 8 ohms? Or does it matter all that much? (Also as a side note, I'm puzzled by the abbreviations at each w/c description and don't know whether I need to know.)
The Elacs will work just fine with the Onkyo.
You are meant to be confused about the power ratings. They don't even give you power with all channels operating at the same time. Some receivers only give you single channel operating power specs.
The letters at the end of the power rating tell you what agency or organization standard of power measurement the rating has used to come up with that number. FTC is US, IEC is EU, JEITA is Japan I think.